MULTIFUNCTION GENERATORWF1947/WF1948
Instruction Manual (Operations)NF Corporation

DA00037851-003

MULTIFUNCTION GENERATORWF1947/WF1948
Instruction Manual (Operations)

——— Preface ———Thank you very
WF1947/WF1948".

much

for

purchasing

our"Multifunction

Generator

To ensure safe and proper use of this electric equipment, please read first "Safety
Precautions" on the following pages.
⚫Caution symbols used in this manual
The following caution symbols are used in this manual. Be sure to observe these caution symbols
and their contents to ensure the safety of the user and avoid damage to the equipment.

WARNING
This symbol indicates information for the avoidance of a hazard that may
endanger human life or cause injury during handling of the equipment.

CAUTION
This symbol indicates information for the avoidance of personal injury or
equipment damage during handling of the equipment.
⚫This manual has the following chapter organization.
The instructions for the external control (GPIB, USB) are provided in a separate manual
included in the attached CD-ROM.
If using this equipment for the first time, start with "1. Outline."

Operations
1.

OutlineThis chapter describes the overview and brief operating principles of this product.

2.

Preparations before UseThis chapter describes important preparations before installation and operation.

3.

Panels and I/O Terminals
This chapter describes the functions and operations of the switches and I/O terminals on the panels.

4.

Basic Operation
This chapter describes basic operations.

5.

Saving and Recalling Settings
This chapter describes how to save and recall the settings.

6.

Creating Arbitrary Waveforms
This chapter describes how to input and edit arbitrary waveforms from the panel control.

7.

Convenient Use of 2-channel Equipment (WF1948 Only)
This chapter describes how to coordinate the settings of two channels.

i

WF1947/WF1948

8.

Synchronizing Multiple Units
This chapter describes how to configure a multi-phase oscillator by connecting multiple units ofthis product.

9.

Using External Frequency ReferenceThis chapter describes how to use external frequency reference.

10. Using User-defined Units
This chapter describes the units which users can define by themselves.
11. Other Utility Settings
This chapter describes how to set display and operational details.
12. TroubleshootingThis chapter describes the error messages and handlings when problems occur.
13. MaintenanceThis chapter describes how to perform the operation inspection and performance test.
14. List of Initial Settings
This chapter describes the initial settings.
15. Specifications
This chapter describes the product's specifications (functions and performance).

ii

WF1947/WF1948

——— Safety Precautions ———To ensure safe use, be sure to observe the following warnings and cautions.
NF Corporation shall not be held liable for damages that arise from a failure to observe thesewarnings and cautions.
This product is a Class I equipment (with protective conductor terminal) that conforms to the JIS
and IEC insulation standards.
⚫ Be sure to observe the contents of instruction manual.
This instruction manual contains instructions for safe operation and use of this product.
Be sure to read this manual first before using this product.
All the warnings in this instruction manual are intended to prevent hazards that may lead toserious accidents. Be sure to observe them.
⚫ Be sure to ground the product.
This product uses a line filter, which may cause electric shock if the product is not grounded.
This product is grounded automatically by connecting a three-pin power supply plug to a power
supply outlet with a protective earth contact.
⚫ Check the power supply voltage.
This product operates on the power supply voltage indicated in "2.3 Grounding and Power
Connections" in this instruction manual.
Prior to connecting the power supply, check that the outlet voltage matches the rated power
voltage of the product.
⚫ In case of suspected anomaly
If this product emits smoke, an abnormal smell, or abnormal noise, immediately power it off andstop using it.
If such an abnormal occurs, prevent anyone from using this product until it has been repaired,and immediately report the problem to NF Corporation or one of our representatives.
⚫ Do not use this product when gas is present.
An explosion or other such hazard may result.
⚫ Never remove the cover.
This product has high-voltage portions inside. Absolutely never remove its cover.
Even when the inside of this product needs to be inspected, do not touch the inside. All suchinspections are to be performed by service technicians designated by NF Corporation.

iii

WF1947/WF1948

⚫ Do not modify the product.
Absolutely never modify this product, as this may cause new hazards and may disqualify thisproduct from repair in case of failure.
⚫ Safety-related symbols
The general definitions of the safety-related symbols used on this product are provided below.
Instructions Manual Reference SymbolThis symbol is displayed to alert the user to potential danger and refer him/her to the
instruction manual.
Electric Shock Danger SymbolThis symbol indicates locations that present a risk of electric shock under specificconditions.
The general definitions of the safety-related symbols used in the instruction manual are provided
below.

WARNING

Warning SymbolThis symbol indicates information for the avoidance of a hazard such as electric shock that
may endanger human life or cause injury during handling of the equipment.

CAUTION

Caution SymbolThis symbol indicates information for the avoidance of damage to the equipment during
handling.
⚫ Other symbols
This mark indicates that the outer conductor of the connector is connected to theenclosure.
This mark indicates that the outer conductor of the connector is insulated from theenclosure.
It indicates, however, that the potential difference from the grounding potential isrestricted to 42Vpk or lower for safety (Since this product is grounded when being
used, the potential of the enclosure equals the grounding potential).

⚫ Request about disposal
To protect the environment, ensure that this device is disposed of by an appropriate industrial
waste processor. A battery is not used for this product.

iv

WF1947/WF1948

Table of Contents
Page
1.

2.

3.

Outline ........................................................................................................................... 1-1
1.1

Features .................................................................................................................. 1-2

1.2

Operating Principles ............................................................................................... 1-3

Preparations before Use ................................................................................................ 2-1
2.1

Checking Before Use............................................................................................... 2-2

2.2

Installation ............................................................................................................. 2-4

2.3

Grounding and Power Supply Connection ............................................................. 2-5

2.4

Calibration .............................................................................................................. 2-6

Panels and I/O Terminals ............................................................................................. 3-1
3.1

3.1.1

Front Panel of WF1947 ................................................................................ 3-2

3.1.2

Rear Panel of WF1947 ................................................................................. 3-3

3.1.3

Front Panel of WF1948 ................................................................................ 3-4

3.1.4

Rear Panel of WF1948 ................................................................................. 3-5

3.2

I/O Terminals .......................................................................................................... 3-6

3.2.1

Waveform Output (FCTN OUT) .................................................................. 3-7

3.2.2

Synchronization/Sub-output (SYNC/SUB OUT) ......................................... 3-8

3.2.3

External Modulation/Addition Input (MOD/ADD IN) ................................ 3-9

3.2.4

External Trigger Input (TRIG IN) ............................................................ 3-10

3.2.5

External 10 MHz Frequency Reference Input (10 MHz REF IN) ............ 3-11

3.2.6

Frequency Reference Output (REF OUT) ................................................. 3-12

3.3
4.

Panel Component Names and Functions ............................................................... 3-2

Cautions on Floating Ground Connection ............................................................ 3-13

Basic Operation ............................................................................................................. 4-1
4.1

Power On/Off and Restoration of Settings ............................................................. 4-2

4.1.1

How to Turn Power On/Off .......................................................................... 4-2

4.1.2

Restoration of Settings at Power-on ........................................................... 4-3

4.2

Screen Configuration and Operation ..................................................................... 4-6

4.2.1

Screen Configuration ................................................................................... 4-6

4.2.2

Switching Display Format with Tabs (To Display Waveform Graph) ....... 4-8

4.2.3

Top Menu ................................................................................................... 4-10

4.3

Basic Settings and Operations ............................................................................. 4-11

4.3.1

To Change Frequency, Amplitude, and Other Values .............................. 4-11

4.3.2

To Change Waveforms ............................................................................... 4-13

4.3.3

Shortcut Keys for Changing Basic Parameters ........................................ 4-14

4.3.4

Functions of ENTER/CANCEL/UNDO Key .............................................. 4-15

4.3.5

To Change Display Unit ............................................................................ 4-16

4.3.6

CH1/CH2 Switching Key and Active Channel (WF1948 Only) ................ 4-18
v

WF1947/WF1948

4.3.7

Operations Available on Utility Screen .................................................... 4-19

4.3.8

To Restore Initial Settings ........................................................................ 4-21

4.3.9

Output On/Off Operation .......................................................................... 4-21

4.4

Setting Methods for Main Items .......................................................................... 4-23

4.4.1

Configuration of Text Display Screen in Continuous Oscillation Mode .. 4-23

4.4.2

To Set Oscillation Mode ............................................................................. 4-23

4.4.3

To Set Waveforms ...................................................................................... 4-24

4.4.4

To Set Frequency ....................................................................................... 4-24

4.4.5

To Set Period .............................................................................................. 4-25

4.4.6

To Set Phase .............................................................................................. 4-25

4.4.7

To Set Amplitude ....................................................................................... 4-28

4.4.8

To Set DC Offset ........................................................................................ 4-30

4.4.9

To Set Output Level with High/Low Level ............................................... 4-31

4.4.10To Set Waveform Polarity and Amplitude Range ..................................... 4-32

4.4.11

How to Use Auto Range/Range Hold for Output Voltage ......................... 4-34

4.4.12

To Set Load Impedance ............................................................................. 4-35

4.4.13To Add External Signal ............................................................................. 4-36

4.4.14

To Set Duty of Square Wave ..................................................................... 4-38

4.4.15

To Set Pulse Width and Leading/Trailing Time of Pulse Wave ............... 4-40

4.4.16

To Set Ramp Wave Symmetry ................................................................... 4-43

4.4.17

To Inhibit Synchronization Output Signal (in Continuous Oscillation Modeand Sine Wave is Selected).......................................................................................... 4-43
4.5

Using Arbitrary Waveforms ................................................................................. 4-44

4.6

Setting and Operation of Modulation .................................................................. 4-45

4.6.1

Modulation Types ...................................................................................... 4-45

4.6.2

Screen for Setting and Operation of Modulation ...................................... 4-46

4.6.3

Common Setting and Operation of Modulation ........................................ 4-48

4.6.4

Setting FM ................................................................................................. 4-51

4.6.5

Setting FSK ............................................................................................... 4-52

4.6.6

Setting PM ................................................................................................. 4-53

4.6.7

Setting PSK ............................................................................................... 4-54

4.6.8

Setting AM ................................................................................................. 4-55

4.6.9

Setting AM (DSB-SC) ................................................................................ 4-57

4.6.10Setting DC Offset Modulation ................................................................... 4-59

4.6.11

Setting PWM .............................................................................................. 4-60

4.7

Setting and Operation of Sweep ........................................................................... 4-61

4.7.1

Sweep Types............................................................................................... 4-61

4.7.2

Screen for Setting and Operation of Sweep .............................................. 4-61

4.7.3

Common Setting and Operation of Sweep ................................................ 4-64

4.7.4

Setting Frequency Sweep .......................................................................... 4-73

4.7.5

Setting Phase Sweep ................................................................................. 4-75

4.7.6

Setting Amplitude Sweep .......................................................................... 4-77
vi

WF1947/WF1948

4.7.7

Setting DC Offset Sweep ........................................................................... 4-79

4.7.8

Setting Duty Sweep ................................................................................... 4-81

4.8

5.

Setting and Operation of Burst ............................................................................ 4-83

4.8.1

Burst Oscillation Types ............................................................................. 4-83

4.8.2

Auto Burst .................................................................................................. 4-84

4.8.3

Trigger burst .............................................................................................. 4-87

4.8.4

Gate Oscillation ......................................................................................... 4-92

4.8.5

Triggered Gate Oscillation ........................................................................ 4-97

Saving and Recalling Settings ...................................................................................... 5-1
5.1

Procedure to Save Settings ..................................................................................... 5-2

5.2

Procedure to Recall Settings .................................................................................. 5-3

5.3

Restoring Saved Contents to Initial Settings ........................................................ 5-4

5.4

Changing Setting Memory Name ........................................................................... 5-4

6.

Creating Arbitrary Waveforms ................................................................................... 6-1
6.1

Basics ...................................................................................................................... 6-2

6.2

Display Procedure and Overview of Screen for Creating/Editing Arbitrary

Waveforms ......................................................................................................................... 6-4
6.3

Creating New Arbitrary Waveform ........................................................................ 6-6

6.4

Simple Arbitrary Waveform Creating Example .................................................... 6-7

6.5

Outputting Created Arbitrary Waveform .............................................................. 6-8

6.6

Saving Created Arbitrary Waveform ..................................................................... 6-8

6.7

Identifying Memory Space Required for Saving Arbitrary Waveforms ................ 6-9

7.

Convenient Use of 2-channel Equipment (WF1948 Only) .......................................................... 7-1
7.1

Overview ................................................................................................................. 7-2

7.2

Copying Setting between Channels ....................................................................... 7-3

7.3

Unifying Settings of 2 Channels ............................................................................ 7-5

7.4

Phase Synchronization between Channels ............................................................ 7-6

7.5

Maintaining Both Channels to Same Frequency (2-Channel Coordination,

2-Phase) ............................................................................................................................. 7-7
7.6

Keeping Frequency Difference Constant (2-Channel Coordination, 2-Tone) ....... 7-9

7.7

Keeping Frequency Ratio Constant (2-Channel Coordination, Ratio) ................ 7-11

7.8

Obtaining Differential Output (2-Channel Coordination, Differential) .............. 7-13

8.

Synchronizing Multiple Units ....................................................................................... 8-1
8.1

Connection Procedure ............................................................................................. 8-2

8.2

Performing Synchronization .................................................................................. 8-4

9.

Using External Frequency Reference ........................................................................... 9-1
9.1

Purpose of Using External Frequency Reference .................................................. 9-2

9.2

Connection and Usage Procedure of External Frequency Reference .................... 9-2

10.

Using User-defined Units ........................................................................................ 10-1

10.1

About User-defined Unit ...................................................................................... 10-2

10.2

Display and Setting in User-defined Unit ........................................................... 10-2

10.3

Defining User-defined Units ................................................................................ 10-3
vii

WF1947/WF1948

11.

Other Utility Settings .............................................................................................. 11-1

11.1

Selecting Remote Interface [Remote] ................................................................... 11-2

11.2

Display Setting [Display] ..................................................................................... 11-2

11.3

Modify Knob and Modify Direction Setting [Modify Direction] .......................... 11-2

11.4

Operation Sound Setting [Sound] ........................................................................ 11-3

11.5

Self Diagnosis [Self Check] ................................................................................... 11-3

11.6

Product Information Display [Information] ......................................................... 11-3

12.

Troubleshooting........................................................................................................ 12-1

12.1

Error Messages at Power-on ................................................................................ 12-2

12.2

Error Messages during Operation ........................................................................ 12-3

12.3

Conflict Messages for Modulation ........................................................................ 12-7

12.4

Conflict Message for Sweep .................................................................................. 12-8

12.5

Conflict Message for Burst ................................................................................... 12-9

12.6

Suspected Failure ............................................................................................... 12-10

13.

Maintenance ............................................................................................................. 13-1

13.1

Overview ............................................................................................................... 13-2

13.2

Operation Inspection ............................................................................................ 13-4

13.3

Performance Test .................................................................................................. 13-5

13.3.1Frequency Accuracy Test ........................................................................... 13-5

13.3.2Sine Wave Amplitude Accuracy Test ........................................................ 13-6

13.3.3

DC Offset Accuracy Test ............................................................................ 13-6

13.3.4Sine Wave Amplitude/Frequency Characteristics Test ............................ 13-7

13.3.5Sine Wave Total Harmonic Distortion Test .............................................. 13-8

13.3.6Sine Wave Harmonic Spurious Test ......................................................... 13-8

13.3.7Sine Wave Non-harmonic Spurious Test .................................................. 13-9

13.3.8Square Wave Duty Accuracy Test ............................................................. 13-9

13.3.9Square Wave Leading/Trailingg Time Test ............................................ 13-10

13.3.10

Time Difference Between Channels for 2-Phase (WF1948 Only) ........... 13-10

14.

List of Initial Settings .............................................................................................. 14-1

15.

Specifications ........................................................................................................... 15-1

15.1

Oscillation mode ................................................................................................... 15-2

15.2

Waveform .............................................................................................................. 15-2

15.2.1

Standard Waveform ................................................................................... 15-2

15.2.2

Arbitrary Waveform .................................................................................. 15-2

15.3

Frequency, phase .................................................................................................. 15-3

15.4

Output Characteristics ......................................................................................... 15-3

15.4.1

Amplitude .................................................................................................. 15-3

15.4.2

DC Offset ................................................................................................... 15-4

15.4.3

Load Impedance Setting ............................................................................ 15-4

15.4.4

Waveform Output ...................................................................................... 15-4

15.4.5

Synchronization/Sub-output ...................................................................... 15-4

15.5

Signal Characteristics .......................................................................................... 15-5
viii

WF1947/WF1948

15.5.1

Sine Wave .................................................................................................. 15-5

15.5.2

Rectangular Wave ...................................................................................... 15-5

15.5.3

Pulse Wave ................................................................................................. 15-6

15.5.4

Ramp Wave ................................................................................................ 15-7

15.6

Modulated Oscillation Mode ................................................................................. 15-7

15.6.1

General ....................................................................................................... 15-7

15.6.2FM .............................................................................................................. 15-8

15.6.3

FSK ............................................................................................................ 15-8

15.6.4

PM .............................................................................................................. 15-9

15.6.5

PSK ............................................................................................................ 15-9

15.6.6AM .............................................................................................................. 15-9

15.6.7

DC Offset Modulation ................................................................................ 15-9

15.6.8PWM ........................................................................................................... 15-9

15.7

Sweep Oscillation Mode ...................................................................................... 15-10

15.7.1

General ..................................................................................................... 15-10

15.7.2Frequency Sweep ..................................................................................... 15-11

15.7.3Phase Sweep ............................................................................................ 15-11

15.7.4

Amplitude Sweep ..................................................................................... 15-12

15.7.5

DC Offset Sweep ...................................................................................... 15-12

15.7.6Duty Sweep .............................................................................................. 15-12

15.8

Burst oscillation mode ........................................................................................ 15-12

15.9

Triggers ............................................................................................................... 15-14

15.10 Other I/Os ........................................................................................................... 15-14
15.11 2-Channel Coordination (WF1948 Only) ........................................................... 15-16
15.12 Synchronization of Multiple Units ..................................................................... 15-17
15.13 User-defined unit ................................................................................................ 15-18
15.14 Other Functions .................................................................................................. 15-18
15.15 General Characteristics ...................................................................................... 15-19
Outline dimensional drawing (WF1947) ............................................................. 15-21
Outline dimensional drawing (WF1948) ............................................................. 15-22
Inch rack mount dimensional drawing (for 1 unit) ............................................ 15-23
Inch rack mount dimensional drawing (for 2 units) ........................................... 15-24
Millimeter rack mount dimensional drawing (for 1 unit) .................................. 15-25
Millimeter rack mount dimensional drawing (for 2 units) ................................. 15-26

ix

WF1947/WF1948

Attached Figures and Tables
Page
Figure 1-1 WF1947 Block Diagram .............................................................................................. 1-3
Figure 1-2 WF1948 Block Diagram .............................................................................................. 1-4
Figure 3-1 Front Panel of WF1947 ............................................................................................... 3-2
Figure 3-2 Rear Panel of WF1947 ................................................................................................ 3-3
Figure 3-3 Front Panel of WF1948 ............................................................................................... 3-4
Figure 3-4 Rear Panel of WF1948 ................................................................................................ 3-5
Figure 3-5 Cautions on Floating Ground Connection for WF1947 ............................................. 3-14
Figure 3-6 Cautions on Floating Ground Connection for WF1948 ............................................. 3-14
Table 3-1 Signals Selectable for Synchronization/Sub-output ...................................................... 3-8

x

WF1947/WF1948

1. Outline

1.1

Features .................................................................................................................. 1-2

1.2

Operating Principles ............................................................................................... 1-3

1-1

WF1947/WF1948

1.1 Features

1.1

Features
NF's WAVE FACTORY, "Multifunction Generator WF1947" and "Multifunction Generator
WF1948" are multifunctional oscillators based on DDS (Direct Digital Synthesizer).
WF1947 is a 1-channel device, while WF1948 is a 2-channel device.
• Highest frequency: 30MHz (sine wave), 20MHz (square wave, pulse)• Frequency accuracy: ±(3ppm + 2pHz), high resolution of 0.01μHz. 10MHz external frequency
reference can be used
• Maximum output voltage: 20Vp-p/open, 10Vp-p/50Ω
• Large number of standard waveforms: Sine wave, square wave (variable duty), pulse (variable
pulse width/duty, Leading time, Trailing time), ramp wave (variable symmetry), and so on• Large-capacity arbitrary waveform memory: Maximum 512 K words, saving capacity: 128
waveforms/4 M words• Phase and waveform remain continuous even when frequency is changed or during frequency
sweep.
• Square wave and pulse with variable duty and high resolution of 0.0001%• Pulse with variable Leading/Trailing time
• Various oscillation modes• Continuous oscillation• Modulation: FM, FSK, PM, PSK, AM, DC offset modulation, PWM• Sweep: Frequency, phase, amplitude, DC offset, and duty
• Burst oscillation: Auto burst, trigger burst, gate oscillation, triggered gate oscillation• Intuitive user interface through use of high-resolution QVGA TFT color LCD• Two-channel coordination function with 2 phases, constant frequency difference, constantfrequency ratio, and differential output (WF1948 only)• Floated from enclosure for each channel to reduce the effect of ground loop
• Multiple-phase oscillator can be configured by synchronizing multiple units• USB and GPIB interfaces provided

1-2

WF1947/WF1948

1.2 Operating Principles

1.2

Operating Principles■ WF1947 block diagram
Approx.
230 kS/s
約230kS/s
ANALOGCONT.

D/A

CPLD

±1V

MOD/ADD
IN

LPF

A/D

Waveform
波形メモリ
memory
8Mbit
512Kw
SSRAM

50kHz Bessel

Vref

External
modulation/
外部変調/
External addition
外部加算/
switching
切換え

10MHz BW
PG AMP PG AMP

CONT

±10V

ATT

FCTN
OUT

LPF

Isolation
アイソレーション

16

MAIN
ANALOG
DDS
FPGA

0/-10dB 0/-20dB

16bit-2ch
D/A
x4
×4
オーバ
overサンプリング
sampling

PWR AMPTTL/±3V

SYNC/SUB
OUT

LPF

16
Ref

VCO,
PLL

Waveform
波形同期/変調同期/
sync/Modulation
バースト同期/sync/Burst
スイープ同期/sync/Sweep
スイーフXドライブ
sync/Sweep
X drive
切換え
switching

COMPARATOR

D/AOFFSET

20MHz

100～230V

2.5ppm VC-TCXO

～LINE
AC/DC

10MHz REF IN+12V

for LOGICSYSTEMCONTROLLERREF OUT(CPU, ROM, RAM,REMOTE I/F,MISC LOGIC)

TRIG IN(Chassis
potential)（シャーシ電位）for ANALOG

DC/DCEN PWR
CNTL

POWER

DC/DC
FAN

FRONT
PANEL
UNIT

USB

GPIB

Figure 1-1 WF1947 Block Diagram◼ Analog block• The DDS (direct digital synthesizer) operates at 120 MHz clock and generates various types ofoscillation and waveform. The modulation, sweep, and burst are also processed within the DDS
FPGA.
• The digital waveform generated by the DDS are controlled by the specified polarity (normal,
inversed) and the amplitude range (-FS/0, ±FS, 0/+FS). After digital amplitude adjustment, its
signal is input into the D/A converter.
• Also, in the D/A converter, analog amplitude control is performed, and the waveform converted
into analog signal is smoothed by the LPF (lowpass filter).
• The amplitude is controlled in 10 dB steps by the PG AMP (programmable gain amplifier).
• The external addition signal and DC offset are added to the PG AMP output. If the required
output voltage is ±400mV/open or less, output is done via x1/5 ATT. If the required output
voltage exceeds ±2V/open, then output is done via x5 amplifier.
• The maximum output voltage of the product is either 20 Vp-p, 4 Vp-p, or 800 mVp-p, dependingon whether the x1/5 ATT or x5 amplifier is used. In conjunction with this, the external addition
gain is either x10, x2, or x0.4.
• The external modulation signal is passed through the LPF, converted by the A/D converter, andthen input into the DDS.

1-3

WF1947/WF1948

1.2 Operating Principles◼ WF1948 block diagram

Block
ANALOG CH2部
Block
ANALOG CH1部
Approx.
230 kS/s
約230kS/s
Waveform
memory
波形メモリ
8Mbit
512Kw
SSRAM

A/D

ANALOGCONT.
D/A

CPLD

±1V

MOD/ADD
IN

LPF

50kHz Bessel

Vref

External
modulation/
外部変調/
External addition
外部加算/
switching
切換え

10MHz BW
PG AMP PG AMP

CONT

±10V

ATT

FCTN
OUT

LPF

Isolation
アイソレーション

16

MAIN
ANALOG
DDS
FPGA

0/-10dB 0/-20dB

16bit-2ch
D/A

PWR AMP×4x4
オーバ
overサンプリング
sampling

TTL/±3V

SYNC/SUB
OUT

LPF

16
Ref

VCO,
PLL

Waveform
波形同期/変調同期/
sync/Modulation
バースト同期/sync/Burst
スイープ同期/sync/Sweep
スイーフXドライブ
sync/Sweep X
drive切換え
switching

COMPARATOR

D/AOFFSET

20MHz

100～230V

2.5ppm VC-TCXO

～LINE
AC/DC

10MHz REF IN
REF OUT(CPU, ROM, RAM,REMOTE I/F,MISC LOGIC)

TRIG IN CH1

TRIG IN CH2
FRONT
PANEL
UNIT

USB

+12V

for LOGICSYSTEMCONTROLLER(Chassis
potential)（シャーシ電位）for ANALOG
(CH1)

DC/DC

POWER

DC/DC

CH1
for ANALOG(CH2)EN PWR
CNTL

FAN
DC/DC

CH2

GPIB

Figure 1-2 WF1948 Block Diagram• The analog block is insulated from the system controller block located in the enclosure potential.
• In WF1948, the analog block includes 2 channels, each of which is individually isolated from theenclosure potential.
◼ System controller block• This block performs the control of analog block, including the display, panel key processing,remote control (GPIB, USB) processing, trigger input processing, frequency reference control,
DDS control, amplitude, and DC offset.
• A 20 MHz crystal oscillator is used as the reference oscillator for the DDS.
• This block sends the signal for synchronization of multiple units to REF OUT (frequency
reference output), and the signal for synchronization between channels (onl y WF1948) to theanalog block of each channel.
◼ Power supply block• The equipment continues to drow power even if the power switch is in standby.
• Control (reset, shut-down, etc.) of each power supply circuit in WF1947/WF1948 is performedby operating the power switch.

1-4

WF1947/WF1948

2. Preparations before Use

2.1

Checking Before Use............................................................................................... 2-2

2.2

Installation ............................................................................................................. 2-4

2.3

Grounding and Power Supply Connection ............................................................. 2-5

2.4

Calibration .............................................................................................................. 2-6

2-1

WF1947/WF1948

2.1 Checking Before Use

2.1

Checking Before Usea) Ensuring safety
To ensure equipment operator's safety, be sure to read the following sections of the instruction
manual at the beginning.
•"Safety Precautions" (provided at the beginning of this instruction manual)•"2.3 Grounding and Power Supply Connection"b) Inspection of external appearance and accessories
If you find anything wrong (e.g., any damages or dents) on the outside surface of the cardboard
box container, please be extremely careful to ensure that the equipment has not been affected,
when you open the container and take out the content.
Please inspect the equipment carefully after taking it out from the cardboard container.
If you find any damages in external appearance or anything missing for accessories, pleasecontact NF Corporation or NF’s agent/dealer.
• Appearance check
Check whether or not the equipment has any damages or dents on the panel surface, or at
knobs or connectors.
• Configuration and accessories check
The configuration of this product is shown below. Ensure that there is nothing missing andnothing damaged for the accessories.

Main unit ............................................................................................................ 1
Instruction Manual .............................................................................................. 1
CD (PDF instruction manuals, application software) .......................................... 1
PDF instruction manuals:
Operations, External Control
Arbitrary Waveform Editing Software
Application Software:
Arbitrary Waveform Editing Software, LabVIEW driver,Sample program
Set of power cords (2m, with 3-pole plug) .......................................................... 1

WARNING
This product has high-voltage portions inside. Absolutely never remove its cover. No one
except the service technicians certified by NF Electronic Instruments are allowed to check or
touch the inside of this equipment. Do not touch the inside by yourself in any case.
c) Repackaging
When you re-pack the equipment for transportation, etc., use a box with appropriate strength andsize margin and some padding which can support the weight, to protect the equipment
sufficiently.

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WF1947/WF1948

2.1 Checking Before Used) Rack mount adapters (optional)
Adapters for mounting the equipment on a 19-inch IEC, EIA standard rack, or JIS standard rack.
There are four types of adapter in total, adapter for one unit and adapter for two units (forside-by-side mounting) for each product model.
They must be purchased separately.

2-3

WF1947/WF1948

2.2 Installation

2.2

Installationa) Installation location
Do not place the equipment with the rear side down. It may damage the connectors and hinder
ventilation. Install the equipment with all the four rubber feet and stands on the level plane suchas a desk, so that the equipment will be stationed stable.
b) Installation conditions• This product uses a forced air cooling system with a fan, and for this purpose it has air intake
and outlet ports on the bottom and rear sides. Be sure to install the equipment with its bottom
and rear surfaces 10 cm apart from the wall at minimum to secure air circulation.
• Install the equipment in a location where the temperature and humidity meet the following
conditions:Operating conditions: 0 ~ 40 °C, 5 ~ 85 %RH
Storage conditions: –10 ~ 50 °C, 5 ~ 95 %RH
Use the equipment without condensation. For limitations related to absolute humidity, refer tothe specifications in this manual.
• This equipment is designed to be safe at an altitude up to 2000 m.
• Do not install the device in the following locations:• Place exposed to inflammable gas
This may pose a risk of explosion. Never install, use or operate the equipment in suchenvironment.
• Outdoors, place exposed to direct sunlight, or place near fire or heat source
If the equipment is installed in such environment, it may not meet the performance
specifications or equipment failures may be induced.
• Environment with corrosive gas, moisture or dust, or with high humidity
The equipment could be corroded or damages could be induced due to such environment.
• Place near electromagnetic field source, high-voltage equipment, or power line
This may cause malfunction.
• Place of frequent vibration
Operating the equipment in such environment could cause malfunctions and/or failures.

c) Maintenance of the panel and housing
When the panel/housing surface needs cleaning, wipe it with a soft cloth. To remove persistentcontamination, wipe it with a soft cloth soaked with neutral detergent and wrung out.
Never use such volatile solvent as thinner or benzine, or chemically treated towels, to wipe theequipment surface. Otherwise, the surface treatment might be altered and/or its paint might bedamaged.

d) Rack mounting method
This product can be mounted on the 19-inch IEC, EIA standard rack, or JIS standard rack byusing a rack-mount adapter (option). In a rack, you can mount only one unit, or two units side
by side.
First, attach the rack mount adapter to the main unit, and then mount the main unit in the rack.

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WF1947/WF1948

2.3 Grounding and Power Supply Connection
For the rack mount adapter handling method, refer to the manual included with the adapter.
Following attention should be drawn when you mount the equipment in the rack:• Support this product by all means by installing some supports such as rails on the rack.
• Do not mount this product on an enclosed rack; otherwise, internal temperature rises highenough to induce operational failures.
Prepare ventilation openings on the rack, or install an air flow system in the rack by using afan.
For the dimensional drawings for rack mounting, refer to:Inch rack mount (for 1 unit) ☞ P.15-23
Inch rack mount (for 2 units) ☞ P.15-24
Millimeter rack mount (for 1 unit) ☞ P.15-25
Millimeter rack mount (for 2 units) ☞ P.15-26

2.3

Grounding and Power Supply Connectiona) Grounding
Be sure to ground the product.

WARNING
This product uses a line filter, which may cause electric shock if the product is not
grounded.
To prevent electric shock accidents, connect the product to ground.

This product is grounded automatically by connecting a three-pole power supply plug to athree-pole power supply outlet with a protective earth contact.
b) Power supply conditions
Voltage range: 100 V AC to 230 V AC ± 10% (250 V or lower)
Frequency range: 50 Hz/60 Hz
Power consumption: WF1947: 55 VA or lower, WF1948: 75 VA or lowerc) Connection procedure of the power source1) Confirm that the commercial power source voltage is within the allowable voltage range ofthis product.
2) Connect the power cord into the power supply inlet on the rear side of this product.
3) Connect the power cord into the three-pole power source outlet.

To connect the mains supply, use this power cord or equivalent one.
The detachable power cord is the equipment disconnecting device. It disconnects the mains circuits
from the mains supply before other parts of the equipment.

WARNING
Install the equipment so that the detachable power cord is readily identifiable andeasily reached by the operator.

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WF1947/WF1948

2.4 Calibration

CAUTION
The accessory power supply cable set is designed to be used for thisproduct only. Do not use it for any other product or purposes.

2.4

Calibration

Although somewhat contingent on the usage environment and how often the product is used, conduct
the performance test at least once a year. The performance tests are also recommended immediately
before using the equipment for important measurements or testing.
Performance tests should be conducted by technicians possessing experience in operating measuring
equipment and have a good general knowledge of equipments.
For details on the performance test, ☞ P.13-1

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WF1947/WF1948

3. Panels and I/O Terminals

3.1

Panel Component Names and Functions ............................................................... 3-2

3.2

I/O Terminals .......................................................................................................... 3-6

3.3

Cautions on Floating Ground Connection ............................................................ 3-13

3-1

WF1947/WF1948

3.1 Panel Component Names and Functions

3.1

Panel Component Names and Functions

This section describes the names and functions of the components on the front panel and rear panel.

3.1.1 Front Panel of WF1947
MODE key
Changes the oscillationmode☞P.4-23, P.4-48,
P.4-61, P.4-84
MENU key
Displays the top menu
☞P.4-10
LCD screen

Basic parameters
Allows the waveform, frequency,
amplitude, and DC offset to bechanged
☞P.4-14
Numeric keypad. Used for numericalinput and waveform setting☞P.4-12, P.4-13
Modify knob. Selects items, orincreases/decreases values☞P.4-9Mode display
sectionThe current
oscillation
mode isdisplayed.
☞P.4-6

Arrow key. Selects items, orincreases/decreases values☞P.4-9Triggered lamp
Lights when a trigger is accepted☞P.4-68, P.4-89
Manual trigger key
Used to trigger sweep or burst☞P.4-68, P.4-89
UNDO key
Undo setting changes.
☞P.4-15
Waveform output on/off key
Turns the waveform output to on/off.
When on, the above "ON" lamp is lit☞P.4-21

NEXT key
ENTER key
Switches the setting Fix the setting
Power switch
screenpages☞P.4-2☞P.4-15☞P.4-7
Soft-keys
CANCEL key
The operation items are
Performs a cancel operation
displayed on the LCD☞P.4-15
screen☞P.4-7External trigger input terminal☞P.3-10External modulation/addition input
terminal ☞P.3-9
Sync/sub-output terminal ☞P.3-8
Waveform output terminal☞P.3-7

Figure 3-1 Front Panel of WF1947

3-2

WF1947/WF1948

3.1 Panel Component Names and Functions

3.1.2 Rear Panel of WF1947

Power supply
input☞ P.2-5

Air outlet☞P.2-4GPIB
connectorUSB
connector

Frequency reference output terminal ☞P.3-12
External 10 MHz frequency reference input terminal ☞P.3-11

Figure 3-2 Rear Panel of WF1947

3-3

WF1947/WF1948

3.1 Panel Component Names and Functions

3.1.3 Front Panel of WF1948
MODE key
Changes theoscillation mode
☞P.4-23, P.4-48,
P.4-61, P.4-84
MENU key
Displays the top menu
☞P.4-10
LCD screen

Basic parameters
Modify knob
Allows the waveform,
Selects items, or
frequency,
increases/decreases values
amplitude, and DC offset
to be changed Numeric keypad ☞P.4-9☞P.4-14
Used for numericalinput and waveformsetting☞P.4-12, P.4-13
Arrow key
Selects items, orincreases/decreases values☞P.4-9Mode display
sectionThe current
oscillation
mode andchannel mode
is displayed.
☞P.4-6

Triggered lamp
Lights when a trigger is accepted☞P.4-68, P.4-89
Manual trigger key
Used to trigger sweep or burst☞P.4-68, P.4-89

UNDO key
Undo setting changes.
☞P.4-15
CH2 waveform output on/off key
Turns the waveform output of CH2 to on/off.
When on, the above "ON" lamp is lit☞P.4-21
NEXT key
Switches thesetting
screen pages☞P.4-7

CH1 waveform output on/off key
Turns the waveform output of CH1 to on/off.
When on, the above "ON" lamp is lit☞P.4-21

ENTER key
Fix the setting☞P.4-15

CH1/CH2 switching key
Soft-keys
Switches the channel
The operation items areto be set on the LCD
displayed on the LCD screen
screen.
☞P.4-7CANCEL key☞P.4-18
Power switch
Performs a cancel☞P.4-2operation☞P.4-15

CH2 sync/sub-output terminal ☞P.3-8
CH2 waveform output terminal ☞P.3-7
CH1 sync/sub-output terminal ☞P.3-8
CH1 waveform output terminal ☞P.3-7

Figure 3-3 Front Panel of WF1948

3-4

WF1947/WF1948

3.1 Panel Component Names and Functions

3.1.4 Rear Panel of WF1948
CH2 external trigger input terminal ☞P.3-10
CH1 external trigger input terminal ☞P.3-10

Power supply input☞P.2-5Air outlet ☞P.2-4

GPIB connector

USB connector

Frequency reference output terminal ☞P.3-12
External 10 MHz frequency reference input terminal ☞P.3-11
CH2 external modulation/addition input terminal ☞P.3-9
CH1 external modulation/addition input terminal ☞P.3-9

Figure 3-4 Rear Panel of WF1948

3-5

WF1947/WF1948

3.2 I/O Terminals

3.2

I/O Terminals
WARNINGTo prevent electric shocks, do not apply a voltage exceeding 42 Vpk (DC+ AC peak) between the ground of the BNC connectors insulated fromthe enclosure and the enclosure.
Also, do not apply a voltage exceeding 42 Vpk (DC + AC peak) between
the grounds of the BNC connector groups insulated from the enclosure.
"BNC connector groups" used here, indicates multiple BNC connectorsthat are connected to a common ground.
If such a high voltage is applied, the internal voltage limiting elements will
try to reduce the voltage, but a too high voltage may cause the product tobe burned.
☞ P.2-5

CAUTION
Do not apply a voltage from external to the output terminals.
This may damage the product.

CAUTION
Do not apply a voltage exceeding the maximum allowable voltage to the
input terminal. This may damage the product.

CAUTION
If a difference in potential exists between the ground of a BNC connector
insulated from the enclosure and the enclosure, do not short-circuit the
hot side of that BNC connector and the enclosure. This may damage theproduct.

CAUTION
If a difference in potential exists between the grounds of BNC
connectors, do not short circuit these BNC connector grounds. This may
damage the product.

3-6

WF1947/WF1948

3.2 I/O Terminals

3.2.1 Waveform Output (FCTN OUT)WF1947

WF1948CH1 FCTN OUT[Insulated fromenclosure]

FCTN OUT[Insulated fromenclosure]

CH2 FCTN OUT[Insulated fromenclosure]This is the main output.
As a mechanical switch is used to turn the waveform output on or off, chattering may occur whenturning the output on/off, and this may cause unintended waveforms to be output. If you connect
the product to an equipment which may malfunction due to chattering, keep the waveform output
always on, and use the burst oscillation and gate oscillation to start/stop the oscillation.

◼ Output Characteristics
Output voltage
Output impedance
Load impedance
Signal GND

Maximum ±10 V/open50Ω
0Ω or higher (short-circuit protection provided)
Insulated from the enclosure (maximum 42 Vpk).
In WF1948, also insulated between channels (maximum 42 Vpk)

3-7

WF1947/WF1948

3.2 I/O Terminals

3.2.2 Synchronization/Sub-output (SYNC/SUB OUT)WF1947

WF1948CH1SYNC/SUB OUT[Insulated fromenclosure]

SYNC/SUB OUT[Insulated fromenclosure]

CH2
SYNC/SUBOUT[Insulated fromenclosure]

A synchronization signal is output according to the waveform or oscillation status. This signal can beused as the synchronization signal for oscilloscope. As shown in the following table, the output
signal can be selected according to the oscillation mode.
Table 3-1 Signals Selectable for Synchronization/Sub-output
Oscillation mode
Selectable output signal
All
50% duty TTL level logic signal that rises at zero degrees reference
phase of waveform output (hereinafter, reference phasesynchronization signal).
The phase relationship with waveform output can be changed ☞P.4-24Modulation mode with•Reference phase synchronization signal
internal modulation source•Internal modulation signal (-3 V to +3 V/open)•TTL level logic signal synchronized with internal modulation☞ P.4-48
signalSweep oscillation mode
•Reference phase synchronization signal•Sweep X drive signal (0 V to +3 V/open)☞ P.4-70•TTL level logic signal synchronized with sweep, marker signal
mixing possible
Burst oscillation mode
•Reference phase synchronization signal•TTL level logic signal synchronized with burst oscillation☞ P.4-86, P.4-90,
P.4-94, P.4-99◼ Output Characteristics
Output voltage
Output impedance
Load impedance
Signal GND

TTL level (low: 0.4 V or lower, high: 2.7 V or higher), -3 V to +3
V/open, 0 V to +3 V/open50Ω
50Ω or higher recommended
Same potential as the same channel waveform output, insulated
from the enclosure (maximum 42 Vpk).
In WF1948, also insulated between channels (maximum 42 Vpk)

3-8

WF1947/WF1948

3.2 I/O Terminals

3.2.3 External Modulation/Addition Input (MOD/ADD IN)
WF1947

WF1948

MOD/ADD IN[Insulated fromenclosure]

CH1
MOD/ADD IN[Insulated fromenclosure]

CH2
MOD/ADD IN[Insulated fromenclosure]

When the modulation source is external in the modulation mode except FSK and PSK, an external
modulation signal is input. In the FSK or PSK modulation mode, the external trigger input is used
as external modulation signal input.
When not used as external modulation signal input, this terminal can be used as the external
addition signal input to the waveform output. The gain during external addition is x0.4, x2, or x10.
External modulation input ☞ P.4-49
External addition input ☞ P.4-36◼ Input Characteristics
Input voltage
Maximum allowable input
Input impedance
Input frequency
Signal GND±1 V full scale
± 2V
10kΩ
During modulation: DC to 40 kHz (-3 dB)
During addition: DC to 10 MHz (-3 dB)
Same potential as the same channel waveform output, insulated
from the enclosure (maximum 42 Vpk).
In WF1948, also insulated between channels (maximum 42 Vpk)

3-9

WF1947/WF1948

3.2 I/O Terminals

3.2.4 External Trigger Input (TRIG IN)
WF1947

WF1948

CH2 TRIG IN

TRIG IN

CH1 TRIG IN

This terminal can be used as external trigger input in the following cases. The polarity setting can bechanged.
• Start trigger of single-shot sweep ☞ P.4-68• Start trigger of gated single-shot sweep ☞ P.4-68• Start trigger of trigger burst oscillation ☞ P.4-89• Gate of gated oscillation ☞ P.4-93• Trigger of triggered gate oscillation ☞ P.4-99
It can also be used as the external modulation input for FSK and PSK.☞ P.4-49◼ Input Characteristics
Input voltage
Maximum allowable input
Input impedance
Signal GND

TTL level (low: 0.8 V or lower, high: 2.6 V or higher)-0.5V ~ +5.5V
10 kΩ, pull up to +3.3 V
Same potential as the enclosure

3-10

WF1947/WF1948

3.2 I/O Terminals

3.2.5 External 10 MHz Frequency Reference Input (10 MHz REF IN)
WF1947

WF1948

10MHz REF IN[Insulated from enclosure]

10MHz REF IN[Insulated from enclosure]This terminal can be used for the following purposes.
◼

When frequency accuracy higher than the specification of this product is required, orwhen you want to use the same frequency reference as a different signal generator
Input the 10 MHz reference signal from an external frequency standard or another signal
generator.
Turn the external frequency reference setting to enable. ☞ P.9-4◼

To unify the frequency and phase of multiple WF1947/WF1948 units
Connect the frequency reference output of the master unit in a synchronous connection ofmultiple units or the higher-level WF1947/WF1948 to the external 10 MHz frequency reference
input of the lower-level WF1947/WF1948.
Set the frequency setting of each unit to the same value.
Also, enable the external frequency reference setting of the lower-level equipment, and performthe phase synchronization on the master unit. ☞ P.8-4
The frequency accuracy of the connected WF1947/WF1948 units are all the same as that of themaster unit.
An external frequency standard can be used as the master unit.

◼ Input Characteristics
Input voltage
Maximum allowable input
Input impedance
Input frequency
Input waveform
Signal GND

0.5Vp-p ~ 5Vp-p
10Vp-p1kΩ, AC coupled
10MHz (± 0.5%(± 50kHz))
Sine or square wave (50 ±5% duty)
Insulated from the enclosure and each channel waveform output(maximum 42 Vpk)

3-11

WF1947/WF1948

3.2 I/O Terminals

3.2.6 Frequency Reference Output (REF OUT)WF1947

WF1948REF OUTREF OUTThis terminal is used to unify the frequency and phase of multiple WF1947/WF1948 units.
Connect the frequency reference output of the master unit in a synchronous connection of multiple
units or the higher-level WF1947/WF1948 to the external 10 MHz frequency reference input of thelower-level WF1947/WF1948. ☞ P.8-2◼ Output Characteristics
Output voltage
Output impedance
Output frequency
Output waveform
Signal GND

1Vp-p / 50Ω
50Ω, AC coupled
10MHz
Square wave
Same potential as theenclosureCheck
Do not connect any equipment other than WF1947, WF1948, and theequipment specified by NF Corporation to the frequency reference output.
The special signal that is output from this terminal during synchronization may
make the operation of such connected equipment unstable.

3-12

WF1947/WF1948

3.3 Cautions on Floating Ground Connection

3.3

Cautions on Floating Ground Connection

The signal ground of the BNC terminals for waveform output, synchronization/sub -output, andexternal modulation/addition input is shared, but since it is insulated from the enclosure (ground
potential), it can be connected to an equipment that has a different potential. Moreover, when theequipment is mounted in a rack, the signal ground is not affected by the potential of the rack .
In WF1948. the above-mentioned BNC terminals are also insulated between channels.
Further, the signal ground of the external 10 MHz frequency reference input is also insulated fromthe enclosure. Therefore, noise caused by ground-loop does not affect the connection with afrequency standard.
Nor does noise caused by ground-loop affect the connection even when synchronously connecting
multiple units of WF1947 and WF1948.
Note that, in all cases, the floating voltage should be limited to 42 Vpk (DC + AC peak) or lower toprevent electric shocks.
The other signal grounds are all connected to the enclosure. The enclosure itself is connected to aprotective earth terminal of the power supply input.

WARNINGTo prevent electric shocks, do not apply a voltage exceeding 42 Vpk (DC +AC peak) between the ground of the BNC connectors insulated from theenclosure and the enclosure.
Also, do not apply a voltage exceeding 42 Vpk (DC + AC peak) between
the grounds of the BNC connector groups insulated from the enclosure.
"BNC connector groups" used here, indicates multiple BNC connectors thatare connected to a common ground.
If such a high voltage is applied, the internal voltage limiting elements will
try to reduce the voltage, but a too high voltage may cause the product tobe burned.

CAUTION
If a difference in potential exists between the ground of a BNC connector
insulated from the enclosure and the enclosure, do not short-circuit the hotside of that BNC connector and the enclosure. This may damage theproduct.

CAUTION
If a difference in potential exists between the grounds of BNC connectors,
do not short circuit these BNC connector grounds. This may damage theproduct.

3-13

WF1947/WF1948

3.3 Cautions on Floating Ground Connection◼ Cautions on floating ground connection for WF1947

Use with potential
difference of 42 Vpk
or less!

Use with potential
difference of 42 Vpk
or less!

Enclosure ground

Use with potential
difference of 42 Vpk
or less!
Enclosure groundFigure 3-5 Cautions on Floating Ground Connection for WF1947◼ Cautions on floating ground connection for WF1948

Use with potential
difference of 42 Vpk
or less!
EnclosuregroundUse with potential
difference of 42 Vpk
or less!

Use with potential
difference of 42 Vpk
or less!

Use with potential
difference of 42
Vpk or less!

Enclosure ground

Use with potential
difference of 42 Vpk
or less!

Use with potential
difference of 42 Vpk
or less!

Enclosure groundFigure 3-6 Cautions on Floating Ground Connection for WF1948

3-14

WF1947/WF1948

4. Basic Operation

4.1

Power On/Off and Restoration of Settings ............................................................. 4-2

4.2

Screen Configuration and Operation ..................................................................... 4-6

4.3

Basic Settings and Operations ............................................................................. 4-11

4.4

Setting Methods for Main Items .......................................................................... 4-23

4.5

Using Arbitrary Waveforms ................................................................................. 4-44

4.6

Setting and Operation of Modulation .................................................................. 4-45

4.7

Setting and Operation of Sweep ........................................................................... 4-61

4.8

Setting and Operation of Burst ............................................................................ 4-83

4-1

WF1947/WF1948

4.1 Power On/Off and Restoration of Settings

4.1

Power On/Off and Restoration of Settings

4.1.1 How to Turn Power On/Off◼ Power-on operation

Power off state(standby state)

The start screen is displayed

Press thepower switch

The power is turned on

Once the power is turned on, a self diagnosis test is automatically executed, and then the equip ment
becomes operable.

◼ Power-off operation

The display goes off

Power on state

Press thepower switch

4-2

Power off state(standby state)

WF1947/WF1948

4.1 Power On/Off and Restoration of Settings

4.1.2 Restoration of Settings at Power-on
When the power is turned on/off using the power switch, the settings before the previous power -offare restored when the power is turned on again.
The output on/off setting at power on can be set on the Utility screen. ☞ P.4-19
However, if the power supply to the product is directly cut off while the power is on, the settings are
set to the contents of the setting memory number 1 when the power supply is resumed.
a) Restoration of settings when the power switch is turned on/off while the power supply ison
The most general case is illustrated below.
~LINE
~LINE

Power supply is on

Power supply ison
Settings
AAAPower on state

Press thepower switch

Power supply is cut
off

The power is turned off(standby state)

Power supply is
resumed

In the power off state, even if thepower supply is cut off, it does notaffect the next restore operation.
The power remains off(standby state)

The power remains off

Settings
AAA

Press thepower switch

The power is turned on(The previous settings arerestored)

While the power is off, if the power supply is cut off due to the disconnection of the power cordor the shutoff of the connected breaker, this does not affect the restore operation the next time
the power is turned on again.
4-3

WF1947/WF1948

4.1 Power On/Off and Restoration of Settings• The settings before the previous power-off are restored.
• The output on/off setting at power on can be changed on the Utility screen. ☞ P.4-19

Check
The settings immediately before the power-off can be restored only if the power isturned off using the power switch.

4-4

WF1947/WF1948

4.1 Power On/Off and Restoration of Settingsb) Restoration of settings at power supply on/off
This is the case when you collectively turn on/off the power supply for this product and otherdevices which are mounted in a rack.
When the power supply is cut off while the power is on, the power is automatically turned on
the next time the power supply is resumed.

~LINE
Power supply isonPower supply is cut
off

~LINE

Settings
AAAPower on state
Settings
MMM

The power is turned off

Power supply
is on

Settings
BBB

Power supply is
resumedSetting change
operationThe power is turned on (Thesettings are set to the contents ofsetting memory No. 1)

Power on state

Settings
MMM

Power supply is
cut off

The power is turned off

The power is turned on (Thesettings are set to the contents ofsetting memory No. 1)• The settings before the power-off are not restored.
• The contents of setting memory number 1 are set. ☞ P.5-2• The output on/off setting at power on can be changed on the Utility screen. ☞ P.4-19

Check
As the settings before the power supply is cut off are not restored, specify thecontents of setting memory number 1 in advance if needed.☞ P.5-2

4-5

WF1947/WF1948

4.2 Screen Configuration and Operation

4.2

Screen Configuration and Operation

4.2.1 Screen Configuration
The LCD screen consists of three areas, as shown in the following figure. There is also the mode
display section on the left side of the screen.
Status display area
Display format
switching tabs
Mode display
sectionSetting area

Soft-key display area

◼ Status display area
Displays the status of the product. The following items are displayed.
• Uncalibrated status

UCAL

Displayed when the calibration information of the product is lost due to a problem, and theprescribed performance cannot be maintained. As this indicates a failure, please contact NF
Corporation or one of our representatives.
• Overheating status

TEMP

Displayed when the internal temperature of the product is abnormally high. If this status isdisplayed when the product is used at an ambient temperature of 40°C or less, it indicates a
failure, so please contact NF Corporation or one of our representatives.
• Remote status

USB ,

GPIB

Displayed when the product is controlled via USB or GPIB.
• External frequency reference status

REF

Displays whether a valid signal is input or not, when the external frequency reference isenabled.
Overheating status

Remote status

Uncalibrated status

External frequency
reference status◼ Mode display section
Displays the oscillation mode and the channel mode (WF1948 only) of this product.
•Oscillation mode

Oscillation
mode

The current oscillation mode is displayed.
CONT (continuous oscillation)/MODU (modulated oscillation)/
SWEEP (sweep oscillation)/BURST (burst oscillation)
For details on the oscillation mode setting, ☞ P.4-23•Channel mode (WF1948 only)

Channel mode
(WF1948 only)

The current channel mode is displayed.
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4.2 Screen Configuration and Operation
INDEP (independent)/2PHASE (2-phase)/
2TONE (constant frequency difference)/RATIO (constant frequency ratio)/
DIFF (differential output)
For details on the channel mode setting, ☞ P.7-2◼ Setting area
This area is used to display and set the various parameters.
When multiple display formats can be selected, the display format switching tabs are displayed on
the left side of the screen. ☞ P.4-8
As there are a lot of setting parameters for modulation, sweep, andNEXT key for switching thesetting screen pages

burst oscillation, the setting screen consist of two or three pages.
The setting screen pages can be switched with the NEXT key.

Setting screen page
position display icon

When there are several setting screen pages, an icon indicating
which page is displayed appears at the top center of the screen.
In the left example, the icon indicates that there are two setting
screen pages in total and the second page is currently displayed.

◼ Soft-key display area
This area displays the functions of the soft-keys which are allocated according to the situation.
If six or more soft-keys are allocated, “▼ n/m” is displayed on the right-most soft-key. This
indicates that the set of soft-keys belonging to the current setting screen consists of m stages intotal, and that the set for the nth stage is currently displayed. When you press this right -most key,
the soft-key set for the next stage is displayed.
Indicates that the first of
two stages of soft-keys isdisplayed.
When this key is pressed,
the soft-keys for the nextstage is displayed.

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4.2 Screen Configuration and Operation

4.2.2 Switching Display Format with Tabs (To Display Waveform Graph)
When multiple display formats can be selected, the display format switching tabs are displayed on
the left side of the screen. For example, if the [Graph] tab screen is displayed, you can set theparameters while checking the image of the output waveform.
a) Display format types
The following three types of display formats are provided.
■Text display [Text] (WF1947)or [Single] (WF1948)
Displays the settings for one channel
in text format■ Graph display [Graph]
Displays the settings for one channel inboth text and graph formats. You cangrasp the image of the output waveform.

◼ 2-channel simultaneous display [Dual] (WF1948 only)
Displays the settings of channel 1 and channel 2 in text format, by stacking them vertic ally.

The channel to be set can be switched by using
the CH 1/CH 2 key.

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4.2 Screen Configuration and Operationb) To switch the display format
The Single tab screen
is displayed

1. In the left example, the Single tab
screen is displayed.
On this screen, the settings are
displayed in text format.

The Graph tab isselected

2. Select the Graph tab by using the arrow
keys or the modify knob.
Tab selection

or

The Graph tab screen isdisplayed

3. Press the ENTER key to switch to theGraph tab screen. On this screen, you can
set the parameters while checking theimage of the output waveform.

Check
In WF1948, the display can be switched between 2-channel
simultaneous display and 1-channel display by using the tab.

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4.2 Screen Configuration and Operation

4.2.3 Top Menu
Arbitrary waveform editing, various system settings, saving and recalling settin gs and others canbe done by selecting the desired item from the top menu.
a) To display the top menu
When you press the MENU key, the menu items are displayed on the soft-keys.

The menu items are displayed

When you press the soft-key corresponding to a menu item, the setting screen for that menu item
appears.
b) Operations available using top menu items
In the setting screen for each menu item, the following settings and operations can be
performed.
◼ OSC
Opens the Oscillator setting screen where you can perform almost all settings and operations
other than arbitrary waveform editing. At power on, the Oscillator setting screen is always
displayed.
■ ARB EDIT
Arbitrary waveform editing can be done. ☞ P.6-4■ MEMORY
The settings can be saved to/recalled from the setting memory. ☞ P.5-2■ UTILITY
Various settings and operations can be done. ☞ P.4-19

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4.3 Basic Settings and Operations

4.3

Basic Settings and Operations

4.3.1 To Change Frequency, Amplitude, and Other Valuesa) To change a value with the up/down arrow keys (or the modify knob)
1. Select the desired item with the arrow
keys or the modify knob.
In the left example, the [Frequency]
field is selected.
The frequency
is selected
The current
frequency
value isdisplayed

Item selection

or

2. When you press the ENTER key, the input
field is opened below or above the
The input field selected item, and you can change theis openedcurrent value of the selected item. In thisstate, you can enter a value using thenumeric keypad.

3. Press the left/right arrow keys to move thecursor to the digit to change the value.
The 1 kHzIn the left example, the cursor is moved todigit is to be
the 1 kHz digit.
changed.

Moving the cursor

4. Increment or decrement the value of the digit tobe changed using the up/down arrow keys or themodify knob.
In the left example, the value is changed to 2
The value ofkHz.
the digit is
The change is immediately applied to the output.
now 2

Incrementing/dec
rementing the
value
or

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4.3 Basic Settings and Operations

5. Press the ENTER key to close the input
field.
The input field
has closed

If you press the CANCEL key instead of
ENTER key, the changed value is discarded
and the setting before the change is restored.

b) To change a value with the numeric keypad

1. Select the desired item with the arrow keys or
the modify knob.
In the left example, the [Frequency] field isselected.

The frequency
is selected.
The current
frequency isdisplayed.

Item selection

or

2. When you press a key of the numeric keypad,
The input field
is opened anda value is
input

the input field is opened below or above theselected item, and the numeric value is input.
While inputting numeric values, the left arrow
key serves as the delete key, and the rightarrow key as the zero input key.
Inputting values

3. Press the ENTER key or the unit key
The setting
is changed,
and theinput field
has closed(soft-key) to set the input value andapply it to the output.
If you press the ENTER key, the value isset without prefix such as "k" or "m".

or

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4.3 Basic Settings and Operations

Check
While inputting numeric values, the left arrow key serves as the delete key, andthe right arrow key as the zero input key.

Check
If a setting item is displayed on a soft-key, you can open the input field forthat item by pressing that soft-key.

4.3.2 To Change Waveforms

1. When you press the FCTN key, theavailable waveforms flash on the numeric
keypad.

2. When you press the key under the flashingwaveform on the numeric keypad, thatwaveform is selected and applied to the
output.
As shown in the left figure, pressing the [2]key selects the square wave.
The selected waveform continues to be
displayed after setting the waveform.
The waveform is
set to square
wave

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4.3 Basic Settings and Operations

4.3.3 Shortcut Keys for Changing Basic Parameters
The selection list or input field for frequency, amplitude, and DC offset can be immediately
opened by using the corresponding basic parameter shortcut key.

◼ Frequency
The frequency input field is
opened◼ Amplitude
The amplitude input field is
opened◼ DC Offset
The DC offset input field is
opened

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4.3 Basic Settings and Operations

4.3.4 Functions of ENTER/CANCEL/UNDO Key◼ Functions of ENTER key
The ENTER key can be used to perform the following actions.
•Open the input field or selection list for the selected item.
•Set the value input from the numeric keypad.
•Perform the function of the button displayed on the screen.
■ Functions of CANCEL key
The CANCEL key can be used to perform the following cancellations. Note that once a setting has
been changed, the original setting cannot be restored with this key (can be restored with the UNDO
key described next).
•Close an input field or selection list.
•Discard the value input from the numeric keypad.
•Restore the value changed by using the modify knob.
•Close a setting window or dialog box.
■ Functions of UNDO key
The UNDO key can be used to restore the settings changed by using the ENTER key or the modify
knob. This key also can restore the setting change that has been automatically executed as theresult of the user's operation.
When you press the UNDO key again immediately after the undo operation, the setting before theundo operation is restored.
Note that undo may not work for some operations.

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4.3 Basic Settings and Operations

4.3.5 To Change Display Unita) To change the prefix (unit prefix: k, m, M, etc.)
Frequency is used as an example here. For amplitude and pulse width, you can use a similarway.

1. Select frequency and then press the
ENTER key to open the input field.
The input field is
opened

2. Press the [Prefix] soft key and thePressing[Prefix]
moves thecursor to
before "Hz"cursor will move to before "Hz". The
right arrow key can also be used tomove the cursor to before "Hz".

3. You can use the up/down arrow keys or the modify
knob to change the unit to MHz, kHz, Hz, mHz, or
uHz. This just changes the display unit and decimal
point position, and the setting value itself does notchange.
Changing prefixor

kHz display

MHz display

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4.3 Basic Settings and Operationsb) To change Vp-p, Vrms, user-defined unit, etc.
Amplitude is used as an example here. For frequency and pulse width, you can use a similarway.

1. Select amplitude and then press the
ENTER key to open the input field.

2. Press the [Unit] soft-key to move thecursor to "Vp-p".
You can also press the right arrow key
to move the cursor to "Vp-p".

Changing unit

3. You can use the up/down keys or the modify
knob to change the unit to Vrms, dBV, or auser-defined unit (in the case of sine wave andload impedance Hi-Z). This just changes thedisplay unit and numeric value, and the output
value itself does not change.

Vrms display

ordBV display

Also refer to the followings:• Changing the frequency and period setting ☞ P.4-24, P.4-25.
• Changing the amplitude unit (Vp-p, Vpk, Vrms, dBm, dBV) ☞ P.4-28.
• Changing the pulse width time and duty settings ☞ P.4-40.
• Setting user-defined units ☞ P.10-2.
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4.3 Basic Settings and Operations

4.3.6 CH1/CH2 Switching Key and Active Channel (WF1948 Only)
Each time the CH1/CH2 switching key is pressed, the channel to be
set is switched.
This key is disabled on the setting screens that are not dependent on
the channel.
The channel that is to be set is called "active channel" in this product.
In the burst oscillation mode, etc., the TRIG key works for the active
channel. Even if the screen is changed to a channel-independentsetting screen, the channel that was active up to that point is saved.

CH1 active(CH1 is to be set)

CH1/CH2
switching key
CH1/CH2
switching key

CH2 active(CH2 is to be set)

The current active channel isdisplayed at the top right corneron the Oscillator screen

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4.3 Basic Settings and Operations

4.3.7 Operations Available on Utility Screena) To display the Utility screen

When you press the MENU key, the top
menu is displayed in the soft-key area. In thisarea, press the soft-key corresponding to[UTILITY]. This opens the Utility screen.

b) Utility screen configuration

External 10 MHz
frequency reference
enable/disable

Setting
initialization

External 10 MHz
frequency reference
status display

External addition setting
Output setting at power-on

Phasesynchronization

User-defined unit setting

Remote setting

Indicator setting
Operation sound setting

Modify direction setting

Internal information
display
Channel modesetting(WF1948 only)

Self diagnosis
Frequency
reference output
enable/disable

2-channel samevalue setting
ON/OFF(WF1948 only)Inter-channel
parameter copy
(WF1948 only)•Setting initialization [Reset]
Initializes the settings. The initial settings are continuous oscillation, sine wave, 1 kHz, 0.1
Vp-p/open, and output off. ☞ P.4-21•External 10 MHz frequency reference enable/disable [Ext Reference]
Enable/disable the external 10 MHz frequency reference. ☞ P.9-4•External addition setting [Ext Add]
Sets the external addition gain. The setting can be selected from off, x0.4, x2, and x10.
☞ P.4-36•External 10 MHz frequency reference input status display [10MHz Ref In]
Displays whether a signal that is valid for the external 10 MHz frequency reference input isinput. ☞ P.9-4•Output setting at power-on [Power-On Output]
Sets the output on/off setting at power-on. ☞ P.4-21

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4.3 Basic Settings and Operations•Phase synchronization [φSync]
Performs the inter-unit synchronization during the synchronous connection of multiple units
and the inter-channel synchronization in WF1948.
☞ P.7-6, P.8-4•User-defined unit setting [User Unit]
Set the user-defined units. ☞ P.10-3•Remote setting [Remote]
Select GPIB/USB and sets the GPIB address. The USB ID is also displayed.
☞ P.11-2•Indicator setting [Display]
Sets the backlight of the display.☞ P.11-2•Modify direction setting [Modify Direction]
Sets the item movement direction when the modify knob is turned.☞ P. 11-2
•Operation sound setting [Sound]
Sets the operation sound.☞ P.11-3•Self Diagnosis [Self Check]
Checks the internal status.☞ P. 11-3
•Internal information display [Information]
Displays the firmware version and the latest calibration date. ☞ P. 11-3
•Frequency reference output enable/disable [10MHz Ref Out]
Turns the 10 MHz reference output terminal on/off ☞ P. 8-4•Channel mode setting [Channel Mode] (WF1948 only)
Sets the type of 2-channel coordination operation. You can select the type from independent,
2-phase, constant frequency difference, constant frequency ratio, and differential output.☞
P.7-7, P.7-9, P.7-11, P.7-13•Inter-channel parameter copy [Parameter Copy] (WF1948 only)
Copies the settings between channels.☞ P.7-3•2-channel same value setting On/Off [Both] (WF1948 only)
Turn on/off the operation of setting the same value for both channels.☞ P.7-5

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4.3 Basic Settings and Operations

4.3.8 To Restore Initial Settings
The initial settings can be restored on the Utility screen.
The initial settings are continuous oscillation, sine wave, 1 kHz, 0.1 Vp -p/open, and output off.
For the list of the initial settings, ☞ P.14-1.

1. When you press the MENU key, the top
menu is displayed in the soft-key area. In
this area, press the [UTILITY] soft-key. This
opens the Utility screen.

2. On the Utility screen, select the [Reset] field
and then press the ENTER key.
This initializes the settings.

On the Utility
screen, select[Reset] and thenpress the ENTER
key

4.3.9 Output On/Off Operationa) Operation method on the panel
Each time the waveform output on/off key is pressed, thewaveform output is switched between on and off. When the output
is on, the [ON] lamp above the key is lit.
Output on/off key

When the output is off, the output terminal is open. When the output is on, the output impedanceis 50Ω. The synchronization/sub-output is always on regardless of the on/off setting of the
waveform output. The waveform output is turned on/off by using a mechanical switch. This
generates chattering when the waveform output is turned on/off. Please be careful when you
connect the product to an equipment which may malfunction due to chattering.☞ P.3-7b) Setting at power-on
You can specify the waveform output on/off status when the power is turned on.
The output setting at power-on can be selected from the following three.

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4.3 Basic Settings and Operations• Off [Off]The output is off.
• On [On]The output is on.
• Returns to previous setting [Last State]
The behavior differs as follows according to how the power is turned off the last time.

If the power was turned off the last time with the power switch on the panel→ The settings before the previous power-off are restored.
If the power was turned off the last time by cutting off the power supply→ The output is off.
This is the case when you collectively turn on/off the power supply for this product andother devices which are mounted in a rack.
The operation is done on the Utility screen.

1. When you press the MENU key, the top
menu is displayed in the soft-key area. In thisarea, press the [UTILITY] soft-key. This
opens the Utility screen.

Select [UTILITY] inthe top menu

2. On the Utility screen, select the [Power-On
Output] field and then press the ENTER key.
On the Utility screen, select[Power-On Output] and thenpress the ENTER key

3.

The power-on output setting window is
opened, so select the desired item and thenpress the ENTER key.
The selection list of the output setting
conditions is displayed, so select thedesired item and then press the ENTER
key.

4.

When the power-on output setting iscompleted, select [OK] at the bottom of thewindow, and then press the ENTER key.
The change of the power-on output setting
is applied, and the window is closed.
When you do not want to apply the changeof the power-on output setting, select[Cancel] at the bottom of the window andpress the ENTER key, or press the
CANCEL key.
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4.4 Setting Methods for Main Items

4.4

Setting Methods for Main Items

This section describes how to set the main items that are set in the Oscillator system setting window.
When you press the MENU key while another screen is displayed, the Top menu is displayed. Select[OSC].
We explain by using the text display screen (1-channel display) in the continuous oscillation mode as
an example. The setting screen is 1 page only.

4.4.1 Configuration of Text Display Screen in Continuous Oscillation Mode
The screen to set the basic output waveforms.

Oscillation
Mode

Waveform(Additional selection buttons
may be displayed, dependingon the waveforms.)

Frequency
Amplitude
Polarity andamplitude
range ofwaveform

DC Offset
ChannelMode(WF1948 only)

Phase
Parametersspecific to the
waveform

4.4.2 To Set Oscillation Mode
MODE key

When you press the MODE key, Oscillation
mode list, continuous oscillation (CONT),
modulated oscillation (MODU), sweep
oscillation (SWEEP), and burst oscillation(BURST) are displayed in the soft-key
display area.

Current
oscillation
mode

Oscillation mode list

When you press the soft-key under the desired
oscillation mode, the oscillation mode is changed,
and the current oscillation mode is displayed on theleft indicator.

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4.4 Setting Methods for Main Items

4.4.3 To Set Waveforms

When you press the FCTN key, the [Waveform]
icon is displayed on numeric keypad. Pressing
the numeric key corresponding to the desired
waveform sets the waveform.

The correspondence of each numeric key and the
waveform is shown below:[1] Key: Sine wave [SINE][2] Key: Square wave [SQUARE][3] Key: Pulse wave [PULSE][4] Key: Ramp wave [RAMP][6] Key: Noise [NOISE][7] Key: DC [DC][8] Key: Arbitrary wave [ARB]
The output waveform can be checked with the LED display on the numeric keypad, as well as thecharacters at the top right of the screen.
When you set the waveform as arbitrary wave, the arbitrary waveform stored in the main unit isselected.☞ P.4-44

4.4.4 To Set Frequency

1. Press the FREQ key to open the input fieldof Frequency. Alternatively, select the[Frequency] field and then press the ENTER
key to open the input field.
If there are two or more system setting
windows opened, [Frequency] is always
displayed at the top left on the first page.
If [Period] is displayed in [Frequency] thatshows "Period" instead of "Frequency", press
the FREQ key again or press the soft-key[Freq]. The display switches to the frequency
display.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) ([uHz], [mHz], [Hz], [kHz], or [MHz]) to set the input value andapply it to the output. When the ENTER key is used, Hz is set as the unit.
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4.4 Setting Methods for Main Items

4.4.5 To Set Period
Settings can be performed using the period instead of the frequency.
The following two methods are available to change from the frequency display to the period display: Use the soft-key [Freq]/[Period] to change to the period display
The input field of Frequency opens. When the current Frequency is displayed, the soft -key [Period] isdisplayed. Press the key opens the input field of Period, and the display changes from [Frequency] to[Period].
The soft-key [Period] changes to [Freq]. When the soft-key [Freq] is pressed, then the input field ofFrequency is opened.
 Press the FREQ key twice to change to the Period display
When the shortcut-key FREQ is pressed twice without opening the input field of Frequency, the input
field of Synchronization is opened.
While the input field of Frequency or Period is opened, the display is switched between Frequency
and Period as the FREQ key is pressed.
When the input field of Period appears, set in
the same way as the one for Frequency.
When a numeric value is entered by using thenumeric keypad, the unit key for period setting
is displayed on the soft-key. When changed tothe period display, the displayed is changed
as follows.
Items: Frequency → Period
Unit display: Hz → s
Soft-keys: Period → Freq

4.4.6 To Set Phasea) Setting procedure

1. Select the [Phase] field and then press the
ENTER key to open the phase input field.
If there are two or more system setting
windows opened, [Phase] is always
displayed at the lower left on the first page.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) ([deg]) to set the input value. When the ENTER key is used, deg is
set as the unit.

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4.4 Setting Methods for Main Itemsb) Items changed in the phase setting
The following items can be changed in the phase setting.
◼ The phase difference between phase sync output of Sync/Sub terminal and waveform
output can be changed.
The following figure shows the example of the phase setting of +90 degree. At this time, thezero relative position of waveform output precedes 90 degree from the rising positio n of thereference phase sync output.
Phase setting:+90 degrees
Waveform output

Zero phase position of
the waveform output

Sync/sub-output(reference phase sync
output)90 degrees◼ The oscillation start/stop phase is changed in burst oscillation or gated single-shot
sweep.
The following figure shows the example of the burst oscillation at the oscillation start/stop
position of +30 degree. At this time, the oscillation starts at +30 degree position, and stops also
at +30 degree position.
Burst oscillation ☞ P.4-84, gated sweep ☞ P.4-67.
Phase setting:+30 degrees

Oscillation starts at+30 degrees

Oscillation stops at+30 degrees

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4.4 Setting Methods for Main Items◼ The phase difference between channels can be changed in synchronous
oscillation and 2 phase oscillation (WF1948 only)
The difference between the phase setting of each channel is the phase difference between thechannels.
When [Phase setting of CH2 - Phase setting of CH1] is positive, the waveform of CH2 precedes
the waveform of CH1 as shown in the following figure.
For synchronous oscillation and 2 phase oscillation, ☞ P.7-6, P.7-7

CH1 waveform output

CH2 waveform output

CH1 phase settingCH2 phase setting

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4.4 Setting Methods for Main Items

4.4.7 To Set Amplitudea) Setting procedure

1. Press the shortcut-key AMPTD to
open the amplitude input field. Or
select the [Amplitude] field and thenpress the ENTER key to open theamplitude input field.
If there are two or more systemsetting windows opened, [Amplitude]is always displayed at the top left on
the first page.
[High] is displayed in the [Amplitude]
field. If the high level instead of
amplitude is displayed, press the
AMPTD key again.

Input fieldofamplitude

2. Select the digit to be changed by using the right or left arrow key, and then use theup or down arrow key/the modify knob to increment the value. The change isimmediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit key(soft-key) to set the input value and apply it to the output.
b) To change unit (Vp-p, Vpk, Vrms, dBV, dBm, User-defined unit)

1. When the input field of amplitude opens,
Place thecursor on
the unit

2.

press the soft-key [Unit] to move thecursor to the unit position at the rightend.
The unit can be changed by using theup or down arrow key/modify knob
(unavailable units are not displayed).
Only the display unit is changed withoutchanging the actual output value.

c) Available units differs depending on the waveform.
Vp-p, Vpk, Vrms, dBV, dBm, and user-defined units can be used as the units for amplitude.
However, the waveforms to which the units can be applied are restricted as follows (DC is
excluded).
Unit
Vp-p
Vpk
Vrms
dBV
dBm

User-defined
Unit

Applied waveformStandard waveforms with amplitude rage of ±FS and arbitrary waveforms
Standard waveforms with amplitude rage of 0/+FS, -FS/0 and arbitrary
waveforms
Sine wave and noise
Noise of sine wave.
1Vrms shall be 0dBV.
Sine wave and noise.
The voltage that is 1mW at the specified load impedance shall be 0dBm. For
example, when the load impedance is set as 50 Ω, dBm=223.6mVrms/50Ω.
It is not available when the load impedance is set as Hi-Z.
All waveforms.
For user-defined units, ☞ P.10-2.

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4.4 Setting Methods for Main Itemsd) Restriction on AC + DC
The maximum value of total of AC amplitude and DC offset is restricted to ±10V/open.
For example, when the AC amplitude is 5Vp-p/open, DC offset is restricted to the range from
-7.5V/open to +7.5V/open.
The maximum value also differs depending on the range setting of output voltage or Ext Add
setting.
☞ P.4-32, P.4-34

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4.4 Setting Methods for Main Items

4.4.8 To Set DC Offset

1. Press the shortcut-key OFFSET toa) Setting procedure

Input fieldof DC
Offsetopen the DC offset input field. Or
select the [Offset] field and then press
the ENTER key to open the DC offset
input field.
If there are two or more system setting
windows opened, [Offset] is always
displayed at the top left on the firstpage.
[Low] is displayed in the [Offset] field.
If the low level instead of DC offset isdisplayed, press the OFFSET key
again.

2. Select the digit to be changed by using the right or left arrow key, and then use theup or down arrow key/the modify knob to increment the value. The change isimmediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit key(soft-key) to set the input value and apply it to the output.

b) Restriction on AC + DC
The maximum value of total of AC amplitude and DC offset is restricted to ±10V/open.
For example, when the AC amplitude is 5Vp-p/open, DC offset is restricted to the range from
-7.5V/open to +7.5V/open.
The maximum value also differs depending on the range setting of output voltage or Ext Add
setting.
☞ P.4-34, P.4-37

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4.4 Setting Methods for Main Items

4.4.9 To Set Output Level with High/Low Level
The output level can be set with the top end value (high level) and the bottom end value (low level)of a waveform instead of amplitude and DC offset.
a) To change Amplitude/DC offset display to High/Low display
There are the following three methods to change the amplitude/DC offset display to high/low
display:
 To change to the high/low display by using the soft-key [High]/[Low]
The input field of Amplitude or DC offset opens. When the current value is displayed, thesoft-key [High] or [Low] is displayed. When this soft-key is pressed, the input field of highlevel or low level opens, and the display is changed from [Amplitude], [Offset] to [High], [Low]respectively.
The soft-key [High], [Low] changes to [Ampl], [Offset] respectively. When the soft-key [Ampl],[Offset] is pressed, then the input field of Amplitude or DC offset is opened.
 To change to the High/Low display by pressing the AMPTD key twice
When the shortcut-key AMPTD is pressed twice without opening the input field of Amplitude,
the input field of High level is opened. While the input field of high level opens, the display i s
switched between the amplitude/DC offset as the AMPTD key is pressed.
 To change to the High/Low display by pressing the OFFSET key twice
When the shortcut-key OFFSET is pressed twice without opening the input field of DC offset,
the input field of Low level is opened. While the input field of low level opens, the display isswitched between the amplitude/DC offset as the OFFSET key is pressed.

Input field of high level

Input field of low level

When the input field of high level or low level appears, set in the same way as the one for DC
offset. When a numeric value is entered by using the numeric keypad, the unit key for highlevel/low level setting is displayed on the soft-key.
When changed to the high level/low level display, the displayed is changed as follows.
Items: Amplitude → High, Offset → Low
Unit display: Vp-p, Vpk, Vrms, dBV, dBm, V → V
Soft-keys: High → Ampl, Low → Offsetb) Restriction on AC + DC
The high level and low level are restricted to the range from -10V to +10V/open.
The maximum range also differs depending on the range setting of output voltage or Ext Add
setting. ☞ P.4-34, P.4-37

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4.4 Setting Methods for Main Items

4.4.10 To Set Waveform Polarity and Amplitude Rangea) Setting procedure

Selection list (soft-key)

1. Select the [Polarity] field and thenpress the Enter key to open theselection list in the soft-key area.
2. Select the desired polarity andamplitude range from the selection
list. When the corresponding soft-key
is pressed, the polarity and theamplitude range are set and they areapplied to the output. The firstcharacter of the soft-key is "N" when
the polarity is normal.
The first character is "I" in the case ofpolarity reverse. If you want to cancel
the setting, press the [Cancel] key toclose the selection list withoutchanging the setting.

b) What are polarity and amplitude range
You can reverse the polarity or change the amplitude range to single-polarity for each waveform.
The following figure shows the cases with sine waves:
Amplitude range
Polarity

NormalInverted"Reverse" only reverses a waveform without changing the sign of output DC offset.

Check
The polarity setting and amplitude range setting are separate
settings for each waveform.

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4.4 Setting Methods for Main Itemsc) How to determine amplitude range
Pay attention how the waveform changes as the amplitude is changed, and decide the amplitude
range.
By default, a waveform that swings to both polarities is set as ±FS, a waveform with single
polarity is set as
0/+FS.
◼ Example with sine wave and the amplitude range of ±FS
When the amplitude is changed, the amplitude of waveform changes
into the positive and negative symmetry based on the DC offset
position.

AmplitudechangeIt is usually convenient to set a waveform that swings to both polarities
around zero as ±FS.
DC offsetd) Restriction by amplitude range• When the amplitude range is -FS/0 or 0/+FS, the maximum amplitude is half of ±FS.
• When the amplitude range is -FS/0 or 0/+FS, it is equivalent to use only the upper/lower halfof waveform memory. Therefore, the amplitude resolution power decrease by 1bit, comparedwith ±FS.
• The amplitude range for ±FS is set as Vp-p, or set as Vpk for -FS/0 or 0/+FS. Both are thenominal size of peak to-peak of waveform.

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4.4 Setting Methods for Main Items

4.4.11 How to Use Auto Range/Range Hold for Output Voltage
Auto-range is selected by default. The best range is automatically selected according to the amplitude
and DC offset (including high/low level settings) settings. When the range is changed, a transitional
voltage is generated. Therefore, it is controlled so as not to be an excessive voltage.
If the transitional voltage generated on range switching is undesirable, you can fix the range.
However, amplitude precision and a waveform fineness decrease as the amplitude is reduced with t herange fixed.
a) Setting procedure

1. When the range field at the right of
the amplitude display is selected, thecurrent range is displayed under the
When selecting therange field. It is expressed as arange field, thecurrent range is
combination of the maximum output
displayed.
voltage[Vp-p]
andamplitude
attenuator.
When the ENTER key is pressed, theselection list for range processing is
opened in the soft-key area.
2. When [AUTO] is selected from theselection list, it is set as Auto range.
Selecting [HOLD] fixes the range atthat time.
Select the desired range processing,and then press the ENTER key.
Selection list (soft-key)b) Maximum values of Amplitude/DC offset for fixed range
When a range is fixed, the maximum values of amplitude and DC offset, and Ext Add gain are
fixed as shown in the following table.
Range
Amplitude(Maximum output
Max
voltage Vp-p,(Load open
Amplitude
valued)attenuator)
20V, 0dB
20Vp-p20V,-10dB
6.325Vp-p
20V,-20dB
2Vp-p
20V,-30dB
0.6325Vp-p
4V, 0dB
4Vp-p
4V,-10dB
1.265Vp-p
4V,-20dB
0.4Vp-p4V,-30dB
0.1265Vp-p
0.8V, 0dB
0.8Vp-p0.8V,-10dB
0.253Vp-p
0.8V,-20dB
0.08Vp-p0.8V,-30dB
0.0253Vp-p

DC Offset
Max(Load open
valued)AC+DC Max
(Load open
valued)External Add
gain(Rated ±1V)

±10V
±10V
±10V
±10V
±2V
±2V
±2V
±2V
±0.4V
±0.4V
±0.4V
±0.4V

±10V
±10V
±10V
±10V
±2V
±2V
±2V
±2V
±0.4V
±0.4V
±0.4V
±0.4V

×10 or Off
×10 or Off
×10 or Off
×10 or Off
×2 or Off×2 or Off×2 or Off×2 or Off×0.4 or Off
×0.4 or Off
×0.4 or Off
×0.4 or Off

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4.4 Setting Methods for Main Items

4.4.12 To Set Load Impedance
By matching the setting value of the load impedance to an actual loading condition, the amplitude
and the DC offset (including the setting according to high level and low level) can be set with thevoltage that appears to the load end.
The value of the load impedance can be set to the range of 1-10k, 50 or open (Hi-Z). However,if the setting value of load impedance is changed, only the amplitude setting value and DC offset
displayed value are changed. The output voltage when the load is opened does not change.
a) Setting procedure

1. When the load impedance field at theright of the range field is selected andthe ENTER key is pressed, theselection list is displayed in thesoft-key area.

Selection list (soft-key)

2. Select the desired load impedance
condition from the selection list, and
then
press
the
corresponding
soft-key. When [Vari] is selected, avalue of the load impedance can be
set. In this case, the input field of load
impedance value is displayed at theright of the load impedance field.
If nothing is changed, press the
CANCEL key.
Input field of load impedanceis displayedb) Conversion formula
Converted by the following formula:
Load impedance setting value: Rload (Ω)
Output voltage when load is opened: Vopen
Output voltage setting value (load end voltage): Vload
Vload =Rload
 Vopen
50 + Rload

Check• Output impedances is constantly 50Ω.
• Neither the output impedance error nor the output voltage error are corrected.
The precision specification of the output voltage is a value when the load is
opened.

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4.4 Setting Methods for Main Items

4.4.13 To Add External Signal
It is possible to output by adding an external signal to a waveform output of this product.
a) To Connect addition signal
Connect an addition signal to the external modulation/addition input (MOD/ADD IN) BNC
terminal on the front panel of WF1947 or on the rear panel of WF1948.
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WF1947

Addition signal

CH1
Addition signal

CH2
Addition signal

For the input characteristic, ☞ P.3-9.
This BNC terminal is insulated from the chassis, and the same ground electrical potential as the
waveform output of the identical channel. For the floating ground connection, ☞ P.3-13.
b) To activate an addition signal
Ext Add is set in the Utility screen.

1. When the MENU key is pressed, thetop menu opens in the soft-key area.
In this area, press the soft-key
corresponding to [UTILITY]. This
opens the Utility screen.

2. On the Utility screen, select the [ExtAdd] field and then press the Enter
key.

Select [Ext Add] on
the Utility screen,
and then press the
ENTER key

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4.4 Setting Methods for Main Items
External addition
setting window is
opened

3. The external addition setting window

opens. Select the item and then press
the ENTER key.
The selection list of the external
addition conditions is opened, so
Set the external select the desired condition and thenadditionpress the ENTER key. [x0.4][x2][x10]condition.
represents the addition gain.

4. When the external addition setting is

Select [OK]and thenpress theENTER key.

completed, select [OK] at the bottomof the window, and then press the
ENTER key. The change of theexternal addition setting is applied,
and the window is closed.
When you do not want to apply thechange of the external addition
setting, select [Cancel] at the bottomof the window and press the ENTER
key, or press the CANCEL key.

c) If the desired external addition condition cannot be selected◼ External addition cannot be ON (set as × 0.4, × 2, × 10)
An external addition is used.
To use the external addition, change the modulation source to Internal.
The external addition input terminal is sharing with the external modulation input terminal.
Therefore, when External is specified as a modulation source for modulated oscillation except
FSK and PSK, the external addition cannot be used. The external addition setting at this time isalways becomes [Off].
Similarly, when an external addition is used, the external modulation cannot be used (excluding
FSK and PSK).
◼ External addition gain cannot be set as the desired value
The gain of the external addition is decided by the output voltage range.
To increase the external addition gain by a factor of 0.4, set the amplitude and the DC offset
setting so that the output voltage range is 0.8V.
To increase the external addition gain by a factor of 2, set the amplitude and the DC offset
setting so that the output voltage range is 4V.
To increase the external addition gain by a factor of 10, set the amplitude and the DC offse tsetting so that the output voltage range is 20V.
Because the external addition adds to the final stage of a waveform output ( ☞ P.1-3), theaddition gain is closely related to the output voltage range. It is fixed to ten times when the
maximum output voltage of the range is 20V, fixed to twice for 4V, fixed to 0.4 times for 0.8V,
and other addition gains cannot be selected.
Oppositely, when the external addition is used, the maximum output voltage of the range isfixed by the addition gain. Especially, note that the fineness of the amplitude precision and the
waveform might decrease when the amplitude is reduced because it is fixed to 20V range when
the addition gain is ten times.

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4.4 Setting Methods for Main Items

4.4.14 To Set Duty of Square Wave
The waveform is assumed to be set as square wave [Square]. For how to set the waveform, ☞ P.4-13.
The setting unit for duty is % only, and it is not possible to set or display with time.
a) How to set duty

1. When the [Duty] field is selected andthe ENTER key is pressed, the input
field of duty opens.
If there are two or more systemsetting windows opened, [Duty] isalways displayed on the first page.
Input fieldof Duty

2. Select the digit to be changed by using the right or left arrow key, and then use theup or down arrow key/the modify knob to increment the value. The change isimmediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit key(soft-key) ([%]) to set the input value and apply it to the output. Even if the ENTER
key is used, an output is set with %.
b) How to switch duty variable range
Normally, it should be used with Off (standard range).

1. When the [Extend] field is selected
and the ENTER key is pressed, The
selection list for duty variable range
enhancement On/Off opens in thesoft-key area.
If there are two or more systemsetting windows opened, [Extend] isalways displayed on the first page.
Selection list (soft-key)

2. Set and applied in the output, when the desired condition is selected from theselection list, and the corresponding soft-key is pressed.

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4.4 Setting Methods for Main Itemsc) Difference between standard and enhanced duty variable range
Variable range
Standard

Enhanced

Features
Setting range: 0.0100% ~ 99.9900%• Duty can be changed within the range where jitter is low and a pulse
does not disappear.
• The setting range of the duty narrows as the frequency rises..
• The duty is fixed to 50% at 20MHz.
Setting range: 0.0000% to 100.0000% (independent from frequency)• There is jitter of 2.5ns rms or lower typ., and the duty can be always
changed from 0% to 100%.
• The pulse might sometimes disappear when the pulse width of the highlevel or the low level is narrower than that of 8.4ns. However, it becomesequal to the specified duty on average, when there is no oscillating
frequency in ratio-of-integers relations to 120 MHz. (The uncertainty forabout 8.3 ns arises at edge time, when oscillating frequency has aratio-of-integers relation.)• When 0% is set, the waveform is fixed to the low level side, and when
100% is set, the waveform is fixed to the high-level side, and in any case,the pulse is not output.

d) Restriction of duty and frequency when duty variable range is standard
The setting range of the duty is limited by the frequency within the following ranges:
Frequency (Hz)/400,000 ≦Duty (%) ≦100 - Frequency (Hz)/400,000

For example, the variable range at 4MHz is limited to the range from 10% to 90%.
If the above-mentioned restriction is not filled by setting the frequency, the duty is adjusted.

Check
When the duty variable range is enhanced, the frequency might become
lower than the setting because the pulse might sometimes disappear. Do
not use it for the usage in which the frequency should be kept constant.

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4.4 Setting Methods for Main Items

4.4.15 To Set Pulse Width and Leading/Trailing Time of Pulse Wave
The waveform is assumed to be set as pulse wave [Pulse]. For how to set the waveform, ☞ P.4-13.
The pulse width can be set with either time or duty.
The Leading time and the Trailing time can be set with time only.
a) How To Set Pulse Width Time

Input field of
pulse widthtime

1. When the [Width] field is selected and the
ENTER key is pressed, the input field of
pulse width time opens.
If there are two or more system setting
windows opened, [Width] is always
displayed on the first page.
[Duty] is displayed in the [Width] field. If apulse width duty is displayed instead ofpulse width time, press the soft-key[Width] while the input field of the duty
opens. It is switched to the pulse widthtime display.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) to set the input value and apply it to the output. When the ENTER
key is pressed, s is set as the unit.
1. When the [Duty] field is selected and the
ENTER key is pressed, the input field ofb) How to set pulse width duty
pulse width duty opens.
If there are two or more system setting
windows opened, [Duty] is always
displayed on the first page.
[Width] is displayed in the [Duty] field. If a
Pulse width
pulse width duty is displayed instead of
duty input
field
pulse width time, press the soft-key [Duty]
while the input field of the duty opens. It is
switched to the pulse width duty display.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change isimmediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) to set the input value and apply it to the output. When the ENTER
key is pressed, % is set as the unit.

c) To toggle pulse width time and pulse width duty
 Pulse width time → Pulse width duty
The input field of pulse width time opens. When the current pulse width time is displayed, thesoft-key [Duty] is displayed. Press the key opens the input field of Pulse width duty, and thedisplay changes from [Width] to [Duty]. The soft-key [Duty] changes to [Width].

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4.4 Setting Methods for Main Items

 Pulse width duty → Pulse width time
The input field of pulse width duty opens. When the current pulse width duty is displ ayed, thesoft-key [Width] is displayed. Press the key opens the input field of Pulse width time, and thedisplay changes from [Duty] to [Width]. The soft-key [Width] changes to [Duty].
d) Difference between pulse width time setting and duty setting
The following different actions occur, depending on whether to set the pulse width with time or
duty.
Set the pulse
width wit time

Set the pulse
width with duty

The pulse width time is constanteven if the frequency is changed

The pulse width duty is constanteven if the frequency is changede) How to set Leading/Trailing time
The Leading time [LE] and the Trailing time [TE] can be set with time only.

1. To set the Leading time, select the [LE]Rising time
input field

field, and then press the ENTER key. The
input field of Leading time opens.
To set the Trailing time, select the [TE]field, and then press the ENTER key. The
input field of Trailing time opens.
If there are two or more system setting
windows opened, [LE][TE] is always
displayed on the first page.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) to set the input value and apply it to the output. When the ENTER
key is pressed, s is set as the unit.
f)Definition and restriction of pulse width, Leading time and Trailing time
The definitions of pulse width, Leading time and Trailing time are shown in the following

figure.
Pulse width

Rising time

PeriodFalling time

However, the setting range is restricted mutually as for pulse width, Leading time, Trailing time,
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4.4 Setting Methods for Main Items
and frequency as shown below.
If the following restriction is not filled by setting the frequency or the pulse width, the Leading
and Trailing times are first adjusted, and then the pulse width are adjusted.

◼ Limitations on Leading/Trailing time
The Leading time, the Trailing time and the frequency or the period are limited within thefollowing ranges:
Large one either 0.01% of period or 15ns  Rising time
Large one either 0.01% of period or 15ns  Falling timeFor example, the Leading time and the Trailing time are limited to 100ns or longer at 1kHz.

◼ Restriction of pulse width, Leading time and Trailing time
The pulse width time, the Leading time, the Trailing time and the frequency or the period arelimited within the following ranges: When the pulse width is set with duty, the value converted
into time shall be the pulse width time.

Rising time +Falling time× 0.8 ≦ pulse width time ≦ period -Rising time +Falling time

×0.8

For example, when the Leading time and the Trailing time are set as 100ns at 1kHz, the pulse
width time is variable within the range from 160ns to 999.84μs.

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4.4 Setting Methods for Main Items

4.4.16 To Set Ramp Wave Symmetry
The waveform is assumed to be set as ramp wave [Ramp]. For how to set the waveform, ☞ P.4-13.
The setting unit for symmetry is % only, and it is not possible to set or display with time.
a) Setting Method of Symmetry

1. When the [Symm] field is selected and the
ENTER key is pressed, the input field of
symmetry opens.
If there are two or more system setting
pages, [Symm] is always displayed on thefirst page.
Symmetry
input field

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) to set the input value and apply it to the output. When the ENTER
key is pressed, % is set as the unit.
b) Relation between symmetry and waveform
The waveform for one cycle changes as follows by the symmetry setting. The total ratio in the
beginning and the last rising part is symmetry. The phase 0 degree is fixed to zero center
positions of the amplitude, excluding the case that symmetry is 0%.

Phase
zero
degreePhase
zerodegreePhase
zerodegreePhase
zerodegreePhase
zerodegree4.4.17 To Inhibit Synchronization Output Signal (in Continuous Oscillation Modeand Sine Wave is Selected)
When the sine wave is selected in continuous oscillation mode, a sync output signal can be inhibitedby sync signal output [SyncOut] setting of the Oscillator setting screen.
It is possible to reduce interference due to common GND in equipments connected to outside andjump from sync output signals by inhibiting a sync output signal.
Regardless of this setting, a sync output signal is output except for continuous oscillation mode andsine wave.

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4.5 Using Arbitrary Waveforms

4.5

Using Arbitrary Waveformsa) To output an arbitrary waveform
Press the [8]key of thenumeric
keypad to set
an arbitrary
waveform(ARB) output.

Press the FCTN key to display a waveformon the numeric keypad, and then press thekey ([8] key) corresponding to an arbitrary
waveform (ARB).
The wave that is currently set as an arbitrary
waveform appears in the output.
The polarity and the amplitude range of the
waveform can be changed as is the case withother waveforms.

b) To change a waveform of arbitrary waveform
When [>] isselected, theselected arbitrary
waveform isdisplayed
immediately
under the field.

1. When a waveform is set as arbitrary
waveform [ARB], [>] appears to just right of[ARB] that indicates the waveform setting.
When selecting here by using the up or downarrow key/the modify knob, the arbitrary
waveform that is currently selected isdisplayed as shown in the left figure. Whenpressing the ENTER key under suchcondition, then navigates to the selection
screen of arbitrary waveforms.

2. Select the digit to be changed by using the right or left arrow key, and then use
the up or down arrow key/the modify knob to increment the value. The change
is immediately applied to the output.
Or use the numeric keypad to enter the value. Press the ENTER key or the unit
key (soft-key) to set the input value and apply it to the output.

Name of arbitrary waveform
Overview of arbitrary waveform
Arbitrary
waveform
numberList of arbitrary waveforms
currently saved

Fix the changes to exit the
selection screen.
Discard the changes to exit the selection screen.

The changes is not applied to output waveforms until you fix it by using the soft-key [OK].
Arbitrary waveform cannot be created through this screen. For creation of arbitrary
waveform, data format, and memory capacity, ☞ P.6-6.
How to rename is the same as to setting memory. Up to 20 characters can be set.

3. To fix the change and exit the selection screen, press the soft-key [OK].
To discard the change and exit the selection screen, press the soft-key [Cancel].
When the shortcut key for changing basic parameter is pressed, the change is discarded
and exit the selection screen.

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4.6 Setting and Operation of Modulation

4.6

Setting and Operation of Modulation

4.6.1 Modulation Types
The following 8 types of modulations are available.
• FM: Frequency Modulation ☞ P.4-51• FSK: Frequency Shift Keying
Binary frequency deviation modulation. ☞ P.4-52• PM: Phase Modulation ☞ P.4-53• PSK: Phase Shift Keying
Binary phase deviation modulation. ☞ P.4-54• AM: Amplitude Modulation ☞ P.4-55• AM(DSB-SC): Amplitude Modulation (Double Side Band - Suppressed Carrier)AM without carrier frequency element. ☞ P.4-57• DC offset modulation: Offset Modulation ☞ P.4-59• PWM: Pulse Width Modulation ☞ P.4-60

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4.6 Setting and Operation of Modulation

4.6.2 Screen for Setting and Operation of Modulation
This section describes the common screen structure in the modulation oscillation mode.
Settings and operations are performed in the settings and operations are performed in the Oscillator
setting screen. When you press the MENU key while another screen is displayed, the Top menu isdisplayed. Select [OSC] and then press the ENTER key.
a) To set the oscillation mode to modulations
Set theoscillation
mode to[MODU]

Press the MODE key, and then select [MODU] by using thesoft-key to light "MODU" ” in the operation mode display section
on the front panel of the main unit. ( ☞ P.4-23) This changes into
the modulated oscillation mode. There are total 2 pages of thesetting screens in the modulation oscillation mode. You canswitch them by using the NEXT key.

b) First page of the setting screen: Screen To Set Carrier Signal
These are common items independent from oscillation mode. The setting screen for themodulation carrier signals.
Indicates that the first page is displayed

Pressing the NEXT key
switches the display to thesecond page.

c) Second page of the setting screen: Screen for setting the modulation
The following figure is the example of selecting FM as a modulation type.
Indicates that the second
page is displayed
Modulation width
Modulation source
Internal modulation waveform
Internal modulation frequency

Modulation
type

Pressing the NEXT key
switches the display toSynchronization output

the first page.

Modulation type [Type]The types of modulation. Select from FM, FSK, PM, PSK, AM, AM(DSB-SC), DC offset
modulation, and PWM. ☞ P.4-48
Modulation width [Deviation, Depth, HopFreq]
Modulation width. The item name depends on the type of modulation. ☞ P.4-48
Modulation source [Source]
Select the modulation source from the inside or outside. ☞ P.4-49
Internal modulation waveform [ModFctn]
The waveform of the internal modulation source. Select from sine wave, square wave,
triangular wave, rising ramp wave, falling ramp wave, noise, and arbitrary wave. ☞ P.4-48
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4.6 Setting and Operation of Modulation
Internal modulation frequency [ModFreq]
The frequency of the internal modulation source. ☞ P.4-48
Sync output [SyncOut]
The output signal from a sync/sub-output terminal. Select from waveform reference phase
sync signal, internal modulation sync signal, and internal modulation waveform. ☞ P.4-49

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4.6 Setting and Operation of Modulation

4.6.3 Common Setting and Operation of Modulation
This section describes the common settings and operations regardless of the type s of modulation all
together.

a) To modulate oscillation mode → Oscillation mode setting
Press the MODE key, and then select [MODU] by using
the soft-key to light "MODU" in the operation mode display
Set thesection on the front panel of the main unit. (☞ P.4-23)
oscillation
mode toThis changes into the modulated oscillation mode. There[MODU]
are total 2 pages of the setting screens in the modulation
oscillation mode. You can switch them by using the NEXTkey.
b) To select an oscillation type → Oscillation type setting
Select from the following eight types in the modulation types [Type] on the second page ofthe setting screen.
•FM[FM] ☞ P.4-51
Modulation
type•FSK[FSK] ☞ P.4-52•PM[PM] ☞ P.4-53•PSK[PSK] ☞ P.4-54•AM[AM] ☞ P.4-55•AM(DSB-SC)[AM(SC)] ☞ P.4-57•DC offset modulation[OFSM] ☞ P. 4-59
•PWM[PWM] ☞ P.4-60c) To set the carrier condition
Set each parameter of the carrier signals on the first page of the setting screen.
d) To set the modulation width
Set in the modulation width on the second page of the setting screen. The name of displayed
item differs among [Deviation], [Depth], and [HopFreq] depending on the modulation type.
For details, see the description of each modulation type.
e) To modulate with internal signal source
Set the modulation source [Source] as internal [Int] on the second page of the setting screen.
It is necessary to set the internal modulation waveform [ModFctn] and the internal modulation
frequency [ModFreq].
Select the internal modulation waveform [ModFctn] from the following seven types:• Sine wave [Sine]• Falling ramp wave [DnRamp]• Square wave (duty 50%) [Square]• Noise[Noise]• Triangular wave (symmetry 50%) [Triangle]• Arbitrary wave[ARB]• Rising ramp wave [UpRamp]
If the internal modulation waveform is noise, the internal modulation frequency cannot be set.
When the modulation type is FSK or PSK, the internal modulation waveform is fixed to thesquare wave with duty 50%. Therefore, the internal modulation waveform cannot be selected.
When the arbitrary wave is selected as the internal modulation waveform, data is used that is
simply thinned out 4096 points from the head in the arbitrary wave in array format. The
arbitrary waves where [RAW] is displayed in the [Type] field of the selection screen of arbitrary
wave are in array format. The arbitrary waveforms with a value of 17(KB) or higher in the

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4.6 Setting and Operation of Modulationf)[Size] field have original wave size of 4096 points or higher. On the other hand, arbitrary wave
where [Point] is displayed in the [Type] field are in control point format. In arbitrary waves inthis format, the entire wave is developed with 4096 points so that the feature of the waveform
may remain as much as possible. For details of an arbitrary waveform, ☞ P.6-9.
To modulate with external signal source
Set the modulation source [Source] as external [Ext] on the second page of the setting screen.
The input terminal of the external modulation signal is different according to the modulation
type as follows:◼ Modulation type is FM, PM, AM, AM(SC), OSFM, PWM
Enter a modulation signal to the external modulation/addition input terminal. The setting ofmodulation width is the value for signal level of ±1V. Note that if the input level is ±1V orlower, the modulation width is lower than the specified value.
When the external modulation/addition input terminal is used for the external addition input, theexternal modulation function cannot be used.
◼ Modulation type is FSK or PSKEnter a modulating signal (TTL level) to the external triggering input terminal.
The polarity can be set on the screen.

g) To start modulation → Automatically started Restarted with the soft-key [Start].
The modulated oscillation starts automatically when entering into the modulated oscillation
mode.
However, if the modulation setting is not appropriate, the modulation oscillation does not start([Conflict] is displayed at the top center of the screen). When pressing the soft-key [?] displayedon the left end, the message concerning an improper setting appears. When that is changed to aproper setting, modulated oscillation starts. ☞ P.12-7
When the modulation is temporarily stopped, press the soft-key [Start] to restart the modulation.
h) To stop modulation → Soft-key [stop]
The soft-key [Stop] pauses modulation.
When the soft-key [Stop] is pressed under modulation, carrier signals are output without being
modulated. The oscillation mode remains in modulated oscillation mode.
i)

To output modulated sync signal and modulation waveform signal → In sync output
setting
Set in the sync output [SyncOut] on the second page of the setting screen. Select from thefollowing three options:•Signal that synchronizes with reference phase of waveform [Sync]•Signal that synchronizes with internal modulation waveform [ModSync]•Internal modulation waveform [ModFctn]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from thesynchronization/sub-output terminal.
◼ When [ModSync] is selected,
Signals with TTL level that synchronize with the internal modulation waveform are output fromthe synchronization/sub-output terminal. A square wave with duty 50% rising at the zero phase

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4.6 Setting and Operation of Modulationof the internal modulation waveform. When the internal modulation waveform is a noise, it isfixed to the low level.
When a signal under modulation is observed with the oscilloscope etc., it can be used as a
trigger signal of the oscilloscope.
◼ When [ModFctn] is selected,
The internal modulation waveform is output from synchronization/sub-output terminal. The
signal level is ±3V/open.
When the modulation type is FSK or PSK, it cannot be selected.

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4.6 Setting and Operation of Modulation

4.6.4 Setting FM
The output frequency changes according to the instantaneous value of modulation signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of FM
When the modulating signal swings to a positive side, the frequency shift of the output signal
increases.
Modulation sync
signal (during
internal
modulation)
Modulation
signalOutput signalb) To select FM
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
page of the setting screen, and thenpress the Enter key to display theselection list in the soft-key area. Whenthe soft-key FM[FM] is pressed, FM is
In the modulation type setting menu, select [FM].

set.

c) Waveform where FM is unavailable
Noise, pulse wave, and DC cannot perform FM.
d) Setting items necessary for FM
Set the carrier frequency [Freq] on the first page of the setting screen.
Set the peak frequency deviation [Deviation] on the second page of the setting screen.
The output frequency changes within the range of carrier frequency ± peak frequency deviation.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
and modulation frequency [ModFreq].
When the modulation source [Source] is external [Ext], enter the modulating signal to external
modulation/addition input terminal. It reaches the specified peak frequency dev iation at ±1V
input.

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4.6 Setting and Operation of Modulation

4.6.5 Setting FSK
A binary frequency deviation modulation that output frequency is switched between the carrier
frequency and the hop frequency according to the modulating signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of FSK
The phase continuity of output signals is maintained though the frequency changes abruptly.
Modulation signal (during
internal modulation)

Modulation signal (duringexternal modulation, positive
polarity)Hopfrequency

CarrierfrequencyHopfrequency

Output signalb) To select FSK
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
page of the setting screen, and thenpress the Enter key to display theselection list in the soft-key area. Whenthe soft-key FSK[FSK] is pressed, FSK is
In the modulation type setting menu,
Select [FSK].

set.

c) Waveform where FSK is unavailable
Noise, pulse wave, and DC cannot perform FSK.
d) Setting items necessary for FSK
Set the carrier frequency [Freq] on the first page of the setting screen.
Set the hop frequency [HopFreq] on the second page of the setting screen.
The carrier frequency and the hop frequency appear alternately in the output frequency.
When the modulation source [Source] is internal [Int], set the modulation frequency [ModFreq].
Set the polarity of the trigger when the modulation source [Source] is external [Ex t], and thenenter the modulation signal (TTL level) to the external trigger input terminal. When the polarity
is set as positive [High], the carrier frequency is output for low-level input, and the hop
frequency is output for high-level input. When the polarity is set as negative [Low], that isreversed.

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4.6 Setting and Operation of Modulation

4.6.6 Setting PM
The output phase changes according to the instantaneous value of modulation signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of PM
When the modulating signal swings to a positive side, the phase shift of the output signal
increases.
The instantaneous frequency also changes at the same time because the phase changes withtime.

Modulation sync
signal (during
internal modulation)

Modulation signal

Output signalb) To select PM
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
page of the setting screen, and thenpress the Enter key to display theselection list in the soft-key area. Whenthe soft-key PM[PM] is pressed, PM is
In the modulation type setting menu,
Select [PM].

set.

c) Waveform where PM is unavailable
Noise and DC cannot perform PM.
d) Setting items necessary for PM
Set the peak phase deviation [Deviation] on the second page of the setting screen.
The output phase changes within the range of ± peak phase deviation.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
and modulation frequency [ModFreq]. When the modulation source [Source] is external [Ext],
enter the modulating signal to external modulation/addition input terminal. It reaches the
specified peak phase deviation at ±1V input.

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4.6 Setting and Operation of Modulation

4.6.7 Setting PSK
A binary frequency deviation modulation that the output phase offsets according to the modulation
signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of PSK
Because the phase changes abruptly, the output signal waveform is discontinuous.
Modulation signal(during internal
modulation)
Modulation signal(during external
modulation, positive
polarity)

Phase
deviation
additionPhasedeviation zeroPhase
deviation
addition

Output signalb) To select PSK
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
page of the setting screen, and thenpress the Enter key to display theselection list in the soft-key area. Whenthe soft-key PSK[PSK] is pressed, PSK is
In the modulation type setting menu,
Select [PSK].

set.

c) Waveform where PSK is unavailable
Noise and DC cannot perform PSK.
d) Setting items necessary for PSK
Set the phase deviation [Deviation] on the second page of the setting screen.
The state of phase deviation zero and the state of a specified phase deviation appear alternat ely
in the output.
Note that the phase does not change within the range of ± phase deviation.
When the modulation source [Source] is internal [Int], set the modulation frequency [ModFreq].
Set the polarity of the trigger when the modulation source [Source] is external [Ext], and thenenter the modulation signal (TTL level) to the external trigger input terminal. When the polarity
is set as positive [High], the phase deviation of zero is output for low-level input, and thespecified phase deviation is output for high-level input. When the polarity is set as negative[Low], that is reversed.
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4.6 Setting and Operation of Modulation

4.6.8 Setting AM
The output amplitude changes according to the instantaneous value of modulation signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of AM
When the modulating signal swings to a positive side, the amplitude of the output signal
increases.
Modulation sync
signal (during
internal modulation)

Modulation signal

Output signal

Amplitude setting value (Vp-p)/2x(1 + modulation depth (%)/100)

Amplitude setting value (Vp-p)/2x(1 - modulation depth (%)/100)b) To select AM
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
page of the setting screen, and thenpress the Enter key to display the
Select [AM] inthe modulation
type setting
menu.

selection list in the soft-key area. Whenthe soft-key AM [AM] in [2/2] of theselection list is pressed here, AM is set.

c) Waveform where AM is unavailable
AM cannot be performed with DC.
d) Setting items necessary for AM
Set the carrier amplitude [Amplitude] on the first page of the setting screen.
Set the modulation depth [Depth] on the second page of the setting screen.
The output amplitude changes within the range of career amplitude setting value (Vp-p) / 2 x (1± modulation depth (%) / 100). When the modulation depth is 0% or the modulation is stopped,
the output amplitude is half of that in the continuous oscillation mode.
When the modulation depth is 100%, the maximum value of the output amplitude envelope isequal to the career amplitude setting value.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
and modulation frequency [ModFreq]. When the modulation source [Source] is external [Ext],
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4.6 Setting and Operation of Modulationenter the modulating signal to external modulation/addition input terminal. It is at the specified
modulation depth when ±1V is entered.

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4.6 Setting and Operation of Modulation

4.6.9 Setting AM (DSB-SC)
The output amplitude changes according to the instantaneous value of modulation signal. AM
without carrier frequency element.
DSB-SC is abbreviation of Double Side Band - Suppressed Carrier.
For the modulation setting screen and the common operation method, P.4-46, P.4-48a) AM (DSB-SC) example
The amplitude of output signal increases when the absolute value of the amplitude ofmodulation signal is large. The polarity of the output signal reverses when the modulation signal
is negative.
Modulation sync
signal (during
internal modulation)

Modulation signal

Output signal

Amplitude setting value (Vp-p)x modulation depth (%)/100b) To select AM (DSB-SC)
When the oscillation mode [Mode] is set as
modulation [MODU], select the modulation
type [Type] on the second page of thesetting screen, and then press the Enter key
Select[AM(SC)] in
themodulation
type settingmenu.

to display the selection list in the soft-key
area. When the soft-key AM(DSB-SC)[AM(SC)] in [2/2] of the selection

list is pressed here, AM (DSB-SC) is set.
c) Waveform where AM (DSB-SC) is unavailable
AM(DSB-SC) cannot be performed with DC.
d) Setting items necessary for AM (DSB-SC)
Set the carrier amplitude [Amplitude] on the first page of the setting screen.
Set the modulation depth [Depth] on the second page of the setting screen.
The output amplitude changes within the range of career amplitude setting value (Vp -p) x
modulation depth (%) / 100.
When the modulation depth is 100%, the maximum value of the output amplitude envelope isequal to the career amplitude setting value.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
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4.6 Setting and Operation of Modulationand modulation frequency [ModFreq]. When the modulation source [Source] is external [Ext],
enter the modulating signal to external modulation/addition input terminal. It is at the specified
modulation depth when ±1V is entered.

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4.6 Setting and Operation of Modulation

4.6.10 Setting DC Offset Modulation
The DC offset changes according to the instantaneous value of modulation signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48a) DC offset modulation example
When the modulating signal swings to a positive side, the DC offset of the output signal increases.
Modulation sync
signal (during
internal modulation)
Modulation signal

Output signal

DC offset settingb) To select dc offset modulation±Peak DC offset deviation

When the oscillation mode [Mode] is set as
modulation [MODU], select the modulation
type [Type] on the second page of thesetting screen, and then press the Enter key
to display the selection list in the soft-key
area. When the soft-key for DC offset
modulation [OFSM] that is in the selection

In the modulation type setting menu,
Select [(OFSM)]

list [2/2] is pressed here, DC offset
modulation is set.

c) Waveform that dc offset modulation is unavailable
None. All waveforms are included.
d) Setting items necessary for dc offset modulation
Set the carrier DC offset [Offset] on the first page of the setting page.
Set the peak DC offset deviation [Deviation] on the second page of the setting page.
The output DC offset changes within the range of career DC offset setting ± peak DC offset
deviation.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
and modulation frequency [ModFreq]. When the modulation source [Source] is external [Ext],
enter the modulating signal to external modulation/addition input terminal. It reaches the
specified peak DC offset deviation at ± 1V input.

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4.6 Setting and Operation of Modulation

4.6.11 Setting PWM
The duty of the square wave and the pulse wave is changed depending on instantaneous value of themodulation signal.
For the modulation setting screen and the common operation method, P.4-46, P.4-48
a) Example of PWM
When the modulating signal swings to a positive side, the duty of the output signal increases.

Modulation sync
signal (during
internal modulation)

Modulation signal

Output signalb) To select PWM
When the oscillation mode [Mode] is set
as modulation [MODU], select themodulation type [Type] on the second
Select[PWM] inthemodulation
type setting
menu.

page of the setting screen, and then press
the Enter key to display the selection list in
the soft-key area. When the soft-key for
PWM [PWM] that is in the selection list
[2/2] is pressed here, PWM is set.

c) Waveform where PWM is unavailable
PWM can be processed only to the square wave and the pulse wave.
PWM is not available for other waveforms.
d) Setting items necessary for PWM
Set the carrier duty [Duty] on the first page of the setting screen.
Set the peak duty deviation [Deviation] on the second page of the setting page.
The output duty is changed within the range of career duty ± peak duty deviation.
When the pulse-wave is used, The pulse width of the career is fixed to the duty setting andcannot be set with time.
When the modulation source [Source] is internal [Int], set the modulation waveform [ModFctn]
and modulation frequency [ModFreq]. When the modulation source [Source] is external [Ext],
enter the modulating signal to external modulation/addition input terminal. It reaches the
specified peak duty deviation at ± 1V input.

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4.7 Setting and Operation of Sweep

4.7

Setting and Operation of Sweep

4.7.1 Sweep Types
Sweep can be done for the following five types of items:• Frequency sweep, ☞ P.4-73• Phase sweep ☞ P.4-75• Amplitude sweep ☞ P.4-77• DC offset sweep ☞ P.4-79• Duty sweep ☞ P.4-81

4.7.2 Screen for Setting and Operation of Sweep
This section describes the common screen structure in the sweep oscillation mode.
Settings and operations are performed in the Oscillator setting screen. When you press the MENU
key while another screen is displayed, the Top menu is displayed. Select [OSC] and then press the
ENTER key.
a) To set the oscillation mode to sweep
Set the oscillation
mode to[SWEEP]

Press the MODE key, and then select [SWEEP] by using
the soft-key to light "SWEEP" ” in the operation mode
display section on the front panel of the main unit. (☞P.4-23) This switches to the sweep oscillation mode.
There are total 3 pages of the setting screens in thesweep oscillation mode. You can switch them by using
the NEXT key.

b) First page of the setting screen: Screen for basic parameter setting
These are common items independent from oscillation mode. Some settings are invalid
depending on the sweep type.
Indicates that the first page isdisplayed

Pressing the NEXT key
switches the display to theSoft-key has
2 rowssecond page.

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4.7 Setting and Operation of Sweepc) Second page of the setting screen: Screen for setting the sweep (1)The following figure is the example of selecting frequency as a sweep type.
Indicates that the second page isdisplayed

Sweep typeStart value of sweep
Sweep stop value
Sweep time
Trigger of single-shot/gatedsingle-shot sweep

Sweep marker value

Sweep Mode
Sweep function

Pressing the NEXT key
switches the display toSoft-key has
2 rowsthe third page.

Sweep type [Type]
Item to sweep. Select one from among frequency, phase, amplitude, DC offset, and duty. ☞P.4-64
Start value [Start] of sweep
The starting value of sweep.
Sweep stop value [Stop]
The stop value of sweep.
Sweep time [Time]
Transition time to sweep from the starting value to the stop value.
Sweep Mode [SwpMode]
The oscillation mode of sweep. Select from continuous sweep, single-shot sweep, and gate
single-shot sweep.☞ P.4-65
Trigger [Trig]
The trigger condition of single-shot sweep and gated single-shot sweep. Select as a trigger
source from the inside or outside.☞ P.4-68
Sweep function [SwpFctn]
Sweep form. Select from one-way, shuttle. Linear and log are available only when the sweep
type is frequency.☞ P.4-65
Sweep marker value [Marker]
The marker value of sweep.☞ P.4-70

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4.7 Setting and Operation of Sweepd) Third page of the setting screen: Screen for setting the sweep (2)The following figure is the example of selecting frequency as a sweep type.
Indicates that the third page isdisplayed
Stop level of the gatedsingle-shot sweep
Oscillation stop unit of
the gated sweep
Synchronization
outputPressing the NEXT key
switches the display tothe first page.
Soft-key has
2 rowsStop level [StpLvl]
The signal level when gated single-shot sweep is stopped. Set the level by specifying Off or
On. Usually, set to Off.☞ P.4-67
The oscillation stop unit [OscStop] in the gated single-shot sweep
The oscillation stop unit in the gated single-shot sweep. Select from 1 cycle unit and half
period unit. Usually, set to 1 cycle unit.☞ P.4-67
Synchronization output [SyncOut]
The output signal from a sync/sub-output terminal. Select from waveform reference phasesynchronization, sweep synchronization, sweep marker, and sweep X drive.☞ P.4-70

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4.7 Setting and Operation of Sweep

4.7.3 Common Setting and Operation of Sweep
This section describes the common settings and operations regardless of the items to sweep all
together.
a) To sweep oscillation mode → Oscillation mode setting
Press the MODE key, and then select [SWEEP] by using thesoft-key to light "SWEEP" ” in the operation mode display section
Set theoscillation
mode to[SWEEP]on the front panel of the main unit. This switches to the sweep
oscillation mode.
There are total 3 pages of the setting screens in the sweep
oscillation mode. You can switch them by using the NEXT key.

b) To select sweep item → In sweep type setting
Select the items to sweep in the sweep types [Type] on the second page of the setting scre en
from the following five items:
Sweep
Type

• Frequency sweep [Freq], ☞ P.4-73• Phase sweep[Phase] ☞ P.4-75• Amplitude sweep [Amptd] ☞ P.4-77• DC offset sweep [Offset]☞ P.4-79• Duty sweep[Duty] ☞ P.4-81c) To set range and time to sweep
Set the following items on the second page of the setting screen.
• Starting value [Start]• Stop value[Stop]• Sweep time [Time]: Time to change from the starting value to the stop value.
For details, see the description of each sweep type.
d) To set sweep range with center and span
When the input field of the starting/stop value is opened and the current value is displayed on
the second page of the setting screen, the soft-key [Center] or [Span] is displayed. When thiskey is pressed, the input field of the center/span value is opened, and the displayed items arechanged from [Start], [Stop] to [Center], [Span] respectively.
The soft-key [Center], [Span] is also changed to [Start], [Stop]. When the soft-key [Start],[Stop] is pressed here, then the input field of the starting/stop value is opened.
The center value is the average of the starting and stop values. The span value is the absolutevalue of difference of the starting and stop values. If the log sweep of the frequency is selected,
the center value is a linear average value of the starting and the stop value.
If it is changed to the center value or span value, the size correlation of the starting value and thestop value is maintained.

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4.7 Setting and Operation of Sweepe) To sweep as sawtooth wave → In one-way sweep
Set the sweep function [SwpFctn] on the second page of the setting screen as One -way
[OneWay].
For frequency sweep, linear [Lin.OneW] or log [Log.OneW] is available for the slope.
One-way sweep

Sweep valuef)

To sweep as triangular waveform → In shuttle sweep
Set the sweep function [SwpFctn] on the second page of the setting screen as Shuttle [Shuttle].
For frequency sweep, linear [Lin.Shtl] or log [Log.Shtl] is available for the slope.
Shuttle sweep

Sweep valueg) To change upward/downward direction of sweep → Starting/stop value with large/small
Sweep from the starting value toward the stop value for sweep with sawtooth waveform(one-way sweep). The value increases during sweep, when the starting value < stop value during
sweep. Oppositely, the value decreases during sweep, when the starting value > stop value
during sweep.
When the soft-key [St<>Sp] of the soft-key set (displayed as [ 2/2] on the right end soft-key)on the second raw of the second page of the setting screen is pressed, the starting value and thestop value can be swapped.
h) To repeat sweep continuously → In continuous sweep
Set the sweep mode [SwpMode] on the second page of the setting screen as continuous [Cont].
A trigger signal is not necessary.
Set the change time from the starting value to the stop value with sweep time [Time] on thesame 2nd page.
Because the sweep time is the change time from the starting value to the stop value, therepeating period is twice the sweep time setting as shown in following figure, when the sweep
function is shuttle.

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4.7 Setting and Operation of Sweep

Continuous one-way sweep
Stop value

Sweep value
Start value
Sweep time

Frequency sweep
exampleContinuous shuttle sweep
Stop value

Sweep value
Start value

Sweep time

Sweep time

Frequency sweep
examplei)

To start sweep synchronizing with trigger → In single-shot sweep
Set the sweep mode [SwpMode] on the second page of the setting screen as single -shot[Single] .
Because a trigger signal is necessary, set a trigger in trigger [Trig] on the same 2nd page. For
trigger setting, ☞ P.4-68.
Set the change time from the starting value to the stop value with sweep time [Time] on thesame 2nd page.
Sweep once in single-shot sweep every time a trigger is accepted.
The appearance of the change is different as shown in the following figure depending onwhether it is one-way or shuttle sweep function.
In case of one-way sweep, it returns to the start value immediately after the sweep ends.
In case of shuttle sweep, it stands by in sweep terminated state after the sweep ends.
Single-shot one-way sweep
Trigger
Stop value
Sweep value
Start value

Sweep time

Start value

Frequency sweep
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4.7 Setting and Operation of Sweep

Single-shot shuttle sweep
Trigger

Stop value
Sweep value

Start value

Sweep time

Sweep time

Frequency sweep examplej)

To output waveform only when sweep running → In gated single-shot sweep
Set the sweep mode [SwpMode] on the second page of the setting screen as gated single -shot[Gated]. This is an operation that combines gate oscillation with sweep. Sweeps synchronizing
with a trigger. Because a trigger signal is necessary, set a trigger in trigger [Trig] on the same
2nd page. For trigger setting, ☞ P.4-68.
◼ Oscillation start/stop phase
Set oscillation start/stop phase in the phase [Phase] on the first page of the setting screen.
However, in phase sweep, the start phase setting is the oscillation starting phase, and the stop
phase setting is the oscillation stop phase.
◼ Stop level (usually set as Off [Off])
When you want to decide the level while oscillation is stopped apart from the phase, set the stoplevel [StpLvl] on the third page of the setting screen as On [On], and then set the level with %value based on the amplitude full scale. Usually, set to Off [Off]. When [Off] is selected, thesignal level while oscillation is stopped is decided by the phase set in [Phase] on the first pageof the setting screen. For stop level, ☞ P.4-90.
◼ Oscillation stop unit (usually set as 1 cycle [Cycle])
When you want to stop oscillation every half cycle, set the oscillation stop unit [OscStop] as halfcycle [HalfCycle] on the third page of the setting screen. Usually, set to 1 cycle [Cycle]. When it isset as 1 cycle [Cycle], it is oscillation with integer cycle.
Because it ends without fail by every one cycle or half cycle according to the oscillation stop unit
[OscStop] setting, the oscillation time is usually longer than the time set in the sweep time setting.
Gated single-shot one-way sweep
Trigger
Stop value
Sweep value

Start value

Start value

Sweep time

Frequency sweep example

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4.7 Setting and Operation of Sweep

Gated single-shot shuttle sweep
Trigger
Stop value
Sweep value

Start value

Sweep time

Sweep time

Frequency sweep example

Check
In phase sweep, the start phase setting is the oscillation starting phase, andthe stop phase setting is the oscillation stop phase.

k) To set trigger condition of single-shot sweep and gated single-shot sweep
Internal trigger oscillator, external signal, manual trigger operation, and remote trig ger can beused as a trigger.
When a trigger is accepted, the TRIG'D lamp on the TRIG key illuminates.
A trigger condition is set in the trigger [Trig] on the second page of the setting screen.
◼ Trigger source setting
A trigger source can be selected from internal [Int] or external [Ext].
When a trigger source is internal [Int], a trigger period can be set.
When a trigger source is external [Ext], the polarity of a trigger can be set.
When a trigger source is external [Ext], enter a trigger signal with TTL level to the external
trigger input terminal (TRIG IN).
◼ How to use manual and remote triggers
Manual trigger operation and remote trigger operation is effective, regardless of the trigger
source setting.
The soft-key [Start] and TRIG key can be used for manual trigger operation.
However, in case of WF1948, the TRIG key only works on the channel side where display isactive. For the channel where display is active, ☞ P.4-18
When only manual trigger operation and remote trigger operation are used for a trigger, set thetrigger source as external [Ext]. Moreover, we will recommend that the polarity is set as [Off] to
avoid malfunctions caused by exogenous noise.

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4.7 Setting and Operation of Sweepl)

To start sweep → With the soft-key [start] or trigger
In continuous sweep, sweep oscillation mode starts automatically the sweep process. However,if the sweep setting is not appropriate, the sweep oscillation does not start ( [Conflict] isdisplayed at the top center of the screen). When pressing the soft-key [?] displayed on the leftend, the message concerning an improper setting appears. When that is changed to a proper
setting, sweep oscillation starts.☞ P.12-8
If sweep is stopped, press the soft-key [Start] to start the sweep. If the soft-key [Start] is not
displayed, press the right end soft-key [2/2] to toggle the soft-key set.
In case of single-shot sweep or gated single-shot sweep, when a trigger is accepted, the sweep isstarted. However, if the sweep setting is not appropriate, trigger cannot be accepted ([C onflict]is displayed at the top center of the screen). When pressing the soft-key [?] displayed on the leftend, the message concerning an improper setting appears. When it is changed to the correct
setting, a trigger can be accepted.☞ P. 12-8
The soft-key [Start] and the manual trigger key on the panel operate as manual trigger operation,
regardless of the trigger source setting.

m) To pause sweep → With soft-key [stop]
When the soft-key [Stop] is pressed while sweep is running, the sweep stops and enter the state
to output a sweep starting value (not to output a stop value). If the soft -key [Stop] is not
displayed, press the right end soft-key [2/2] to toggle the soft-key set. However, in case of
single-shot sweep or gated single-shot sweep, when a new trigger is accepted, the sweep isstarted again.
n) To pause sweep temporarily → With soft-key [hold]
When pushing [Hold] soft-key while a sequence is executed, the sequence is paused. Afterwards,
when the soft-key [Resume] is pushed, the sweep is restarted at the point where it is paused. If
the soft-key [Hold] or [Resume] is not displayed, press the right end soft-key [2/2] to toggle
the soft-key set.
However, in case of single-shot sweep or gated single-shot sweep, when a new trigger is
accepted during being held, the sweep is started from the beginning.
The soft-key [Hold] and [Resume] are displayed as [Hold] during sweep, and as [Resume]
during pause, at the same position.

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4.7 Setting and Operation of Sweepo) To output sweep starting value → With the soft-key [SttState]
When the soft-key [SttState] is pressed, it enters into the status to output the sweep starting
value.
You can check the status of tested equipment with sweep starting value.
The soft-key [SttState] is displayed in the status to output the sweep starting value or stop value.
If the soft-key [SttState] is not displayed, press the right end soft-key [2/2] to toggle thesoft-key set.
In case of gated single-shot sweep, it is in oscillation status with starting value. To stop theoscillation, press the soft-key [Stop].
p) To output sweep stop value → With the soft-key [StpState]
When the soft-key [StpState] is pressed, it enters into the status to output the sweep stop value.
You can check the status of tested equipment with sweep stop value.
The soft-key [StpState] is always displayed in sweep mode. If the soft-key [StpState] is not
displayed, press the right end soft-key [2/2] to toggle the soft-key set.
In case of gated single-shot sweep, it is in oscillation status with stop value. To stop theoscillation, press the soft-key [Stop].
q) To output sweep sync signal, sweep marker signal, sweep x drive signal → insynchronization setting
Set in the sync output [SyncOut] on the third page of the setting screen. Select from thefollowing four options:• Signal that synchronizes with reference phase of waveform [Sync]• Signal that synchronizes with sweep [SwpSync]• Signal that matches a marker signal to a signal that synchronizes with sweep[SwpSync+Mkr(SwS+Mk)]• X drive signal of sweep [X-Drive]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from thesynchronization/sub-output terminal.
◼ When [SwpSync] is selected,
A TTL level signal that synchronizes with sweep is output from the synchronization/sub-output
terminal. It changes from high to low at the time of starting sweep.
When a signal under sweep is observed with the oscilloscope etc., it can be used as a trigger
signal of the oscilloscope.

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4.7 Setting and Operation of Sweep◼ When [SwpSync+Mkr] is selected,
The rising of sweep sync output is a marker signal. The sweep sync output is low until it reaches themarker value from the sweep starting value. A sync output does not change in the outward of shuttle
sweep.
Timing for the signal under sweep to pass the marker value can be known.
However, there are the following restrictions for time zone when a synchronous sweep output is low.
• Time zone is limited from about 0.05% to 99.95% of the sweep time. Therefore, the time one
does not change even if the marker value is changed if the marker value is close to the starting
value or the stop value.
• Resolution of time zone is limited to the larger one of either 1/32768 of the sweep time or
8.33ns. Therefore, the time zone does not necessarily change even if the marker value ischanged finely.
◼ When [X-Drive] is selected,
A signal with the value of 0 to +3V/open corresponding to sweep is output from thesynchronization/sub-output terminal. The voltage changes linearly in proportion to sweep
elapsed time. The voltage also changes linearly in proportion to sweep elapsed time, even if log[Log-OneWay] and [Log-Shuttle] is selected as the sweep function in frequency sweep.
When a signal during sweep is observed with oscilloscope with X-Y display or X-Y recorder, it
can be used as a signal of the X axis.
The following figure shows the relation between a sweep value and each signal. When the stop
value < the starting value, the slope of the sweep X drive output is contrary to the figure.
One-way sweep, gated one-way sweep
One way
Marker value

ShuttleStop valueMarker value

Stop value

Sweep value

Start value

Sweep sync
signal SwpSync(markerdisabled)
Sweep sync
signal SwpSync+ Mkr (marker
enabled)Start value

Low during
the 1st halfof intervalfrom startvalue tostop value

Low from
start value
to stopvalue

Low from
start value
to marker
value

Low from
start value
to marker
value

Sweep time

Sweep time

Sweep X drive
signal X-Drive

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4.7 Setting and Operation of Sweep

Continuous sweep
One way
Stop value

Sweep value

Sweep sync
signal SwpSync+ Mkr (marker
enabled)Marker valueMarker value

Start value
Sweep sync
signal SwpSync(markerdisabled)

ShuttleStop value

Start value
Low during
the 1st halfof intervalfrom startvalue tostop value

Low from
start value
to marker
value

Low from
start value
to stopvalue

Low from
start value
to marker
value

Low from
start value
to marker
value

Sweep X drive
signal X-Drive

Sweep time

Sweep time

Sweep timer) To assign a marker value for a center value, or to assign a center value for a marker
value
When the soft-key [Ct>Mk] is pressed on the second page, a center value is assigned for amarker value. When the soft-key [Mk>Ct] is pressed, the marker value is assigned for the center
value oppositely. If these soft-keys on the second page of the setting screen are not displayed,press the right end soft-key [1/2] to toggle the soft-key set.

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4.7 Setting and Operation of Sweep

4.7.4 Setting Frequency Sweep
For the sweep setting screen and the common operation method, P.4-61, P.4-64a) Frequency sweep example
Examples of a continuous sweep and linear shuttle.
Shuttle sweep
Stop value
Sweep value
Start value

Sweep time

Sweep time

Output signalb) To select frequency sweep

When the oscillation mode [Mode] is set as
sweep [SWEEP], select the sweep type [Type]on the second page of the setting screen, andthen press the Enter key to display theselection list in the soft-key area. When thesoft-key frequency [Freq] is pressed,
frequency sweep is set.
In the sweep type setting menu,
Select [Freq].

c) Waveform that frequency sweep is unavailable
Noise, pulse, and DC cannot perform frequency sweep.
d) Items necessary for frequency sweep
Set the following items on the second page of the setting screen. The frequency setting on thefirst page of the setting screen is invalid.
• Starting frequency [Start]
The frequency range depends on a waveform.
• Stop frequency [Stop]
The frequency range depends on a waveform.
• Sweep time [Time]Time to change from the starting frequency to the stop frequency.☞ P.4-64• Sweep Mode [SwpMode]
Select from continuous, single-shot, or gated single-shot.☞ P.4-65• Sweep function [SwpFctn]
Select from one-way/shuttle or linear/log.☞ P.4-65
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4.7 Setting and Operation of Sweep
It is possible to set with center frequency [Center], and span frequency [Span], instead of startfrequency, and stop frequency.☞ P.4-64
When sweep mode is single-shot or gated single-shot, it is necessary to set the trigger condition[Trig].☞ P.4-68
Set the following items as needed:• Marker frequency[Marker] (the second page of the setting screen) ☞P.4-70• Stop level [StpLvl] (the third page of the setting screen) ☞P.4-67
The setting used for gated single-shot sweep only.
• Oscillation stop unit of gated single-shot sweep [OscStop] (the third page of the setting screen)☞ P.4-67
The setting used for gated single-shot sweep only.
• Sync output [SyncOut] (the third page of the setting screen) ☞ P.4-70

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4.7 Setting and Operation of Sweep

4.7.5 Setting Phase Sweep
For the sweep setting screen and the common operation method, P.4-61, P.4-64a) Phase sweep example
Examples of a continuous sweep and linear shuttle.
Shuttle sweep
Stop value

Sweep value
Start value

Sweep time

Sweep time

Output signal

When the phase increases, the frequency rises as by the following figure. When the phase
Stopphase falls by following value.
decreases, thefrequency

Stop phase (deg) − スタート位相Starting phase (deg)ストップ位相360

1
スイープ時間Sweep time (sec)b) To select phase sweep
When the oscillation mode [Mode] is set as
sweep [SWEEP], select the sweep type[Type] on the second page of the setting
screen, and then press the Enter key todisplay the selection list in the soft-key
area. When the soft-key phase [Phase] ispressed, phase sweep is set.
In the sweep type setting menu,
Select [Phase].

c) Waveform that phase sweep is unavailable
Noise and DC cannot perform phase sweep.
d) Items necessary for phase sweep
Set the following items on the second page of the setting screen. The phase setting on the firstpage of the setting screen is invalid.
• Starting phase [Start]• Stop phase [Stop]• Sweep time [Time]Time to change from the starting phase to the stop phase.☞P.4-64

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4.7 Setting and Operation of Sweep• Sweep Mode [SwpMode]
Select from continuous, single-shot, or gated single-shot.☞ P.4-65• Sweep function [SwpFctn]
Select from one-way/shuttle.☞ P.4-65
It is possible to set with center phase [Center], and span phase [Span], instead of start phase, andstop phase.☞ P.4-64
When sweep mode is single-shot or gated single-shot, it is necessary to set the trigger condition[Trig].☞ P.4-68
Set the following items as needed:• Marker phase[Marker] (the second page of the setting screen) ☞P.4-70• Stop level [StpLvl] (the third page of the setting screen) ☞P.4-67
The setting used for gated single-shot sweep only.
• Oscillation stop unit of gated single-shot sweep [OscStop] (the third page of the setting screen)☞ P.4-67
The setting used for gated single-shot sweep only.
• Sync output [SyncOut] (the third page of the setting screen) ☞ P.4-70

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4.7 Setting and Operation of Sweep

4.7.6 Setting Amplitude Sweep
For the sweep setting screen and the common operation method, P.4-61, P.4-64a) Amplitude sweep example
Examples of a continuous sweep and linear shuttle.
Shuttle sweep
Stop value

Sweep value
Start value

Sweep time

Sweep time

Output signalb) To select amplitude sweep
When the oscillation mode [Mode] is set as
sweep [SWEEP], select the sweep type[Type] on the second page of the setting
screen, and then press the Enter key todisplay the selection list in the soft-key
area. When the soft-key amplitude [Amptd]
In the sweep type setting menu,
Select [Amptd].

is pressed, amplitude sweep is set.

c) Waveform that amplitude sweep is unavailable
Amplitude sweep cannot be performed with DC.
d) Items necessary for amplitude sweep
Set the following items on the second page of the setting screen. The amplitude setting on thefirst page of the setting screen is invalid.
• Starting amplitude [Start]• Stop amplitude [Stop]• Sweep time [Time]Time to change from the starting amplitude to the stop amplitude.☞ P.4-64• Sweep Mode [SwpMode]
Select from continuous, single-shot, or gated single-shot.☞ P.4-65• Sweep function [SwpFctn]
Select from one-way/shuttle.☞ P.4-65
It is possible to set with center amplitude [Center], and span amplitude [Span], instead of start
amplitude, and stop amplitude.☞ P.4-64
When sweep mode is single-shot or gated single-shot, it is necessary to set the trigger condition[Trig].☞ P.4-68

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4.7 Setting and Operation of Sweep
Set the following items as needed:• Marker amplitude[Marker] (the second page of the setting screen) ☞P.4-70• Stop level [StpLvl] (the third page of the setting screen) ☞P.4-67
The setting used for gated single-shot sweep only.
• Oscillation stop unit of gated single-shot sweep [OscStop] (the third page of the setting screen)☞ P.4-67
The setting used for gated single-shot sweep only.
• Sync output [SyncOut] (the third page of the setting screen) ☞ P.4-70

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4.7 Setting and Operation of Sweep

4.7.7 Setting DC Offset Sweep
For the sweep setting screen and the common operation method, P.4-61, P.4-64a) DC offset sweep example
Examples of a continuous sweep and linear shuttle.
Shuttle sweep
Stop value

Sweep value
Start value

Sweep time

Sweep time

Output signalb) To select dc offset sweep
When the oscillation mode [Mode] is set
as sweep [SWEEP], select the sweep
type [Type] on the second page of thesetting screen, and then press the Enter
key to display the selection list in thesoft-key area. When the soft-key DC
In the sweep type setting menu,
Select [Offset].

offset [Offset] is pressed, DC offset
sweep is set.

c) Waveform that dc offset sweep is unavailable
None. However, when DC is selected as a waveform, the DC level itself is sweeped. In addition,
when DC is selected as a waveform, gated single-shot sweep cannot be performed.
d) Items necessary for DC offset sweep
Set the following items on the second page of the setting screen. The DC offset setting on thefirst page of the setting screen is invalid.
• Start DC offset [Start]• Stop DC offset [Stop]• Sweep time [Time]Time to change from the starting DC offset to the stop DC offset.
☞ P.4-64• Sweep Mode [SwpMode]
Select from continuous, single-shot, or gated single-shot.☞ P.4-65• Sweep function [SwpFctn]
Select from one-way/shuttle.☞ P.4-65
It is possible to set with center DC offset [Center], span DC offset[Span], instead of start DC
offset, stop DC offset.☞ P.4-64

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4.7 Setting and Operation of Sweep
When sweep mode is single-shot or gated single-shot, it is necessary to set the trigger condition[Trig].☞ P.4-68
Set the following items as needed:• Marker DC offset[Marker] (the second page of the setting screen) ☞P.4-70• Stop level [StpLvl] (the third page of the setting screen) ☞P.4-67
The setting used for gated single-shot sweep only.
• Oscillation stop unit of gated single-shot sweep [OscStop] (the third page of the setting screen)☞ P.4-67
The setting used for gated single-shot sweep only.
• Sync output [SyncOut] (the third page of the setting screen) ☞ P.4-70

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4.7 Setting and Operation of Sweep

4.7.8 Setting Duty Sweep
For the sweep setting screen and the common operation method, P.4-61, P.4-64a) Duty sweep example
Examples of a continuous sweep and linear shuttle.
Shuttle sweep
Stop value

Sweep value
Start value

Sweep time

Sweep time

Output signalb) To select duty sweep
When the oscillation mode [Mode] is set
as sweep [SWEEP], select the sweep
type [Type] on the second page of thesetting screen, and then press the Enter
key to display the selection list in thesoft-key area. When the soft-key duty
In the sweep type setting menu,
Select [Duty].

[Duty] is pressed, duty sweep is set.

c) Waveform that duty sweep is unavailable
Only square wave and pulse wave are the target of duty sweep.
d) Setting items necessary for duty sweep
Set the following items on the second page of the setting screen. The duty setting on the firstpage of the setting screen is invalid.
• Start duty [Start]
The range of duty depends on the frequency. Pulse wave further depends on the Leading andTrailing times.☞ P.4-38, P.4-40• Stop duty [Stop]
The range of duty depends on the frequency. Pulse wave further depends on the Leading andTrailing times.☞ P.4-38, P.4-40• Sweep time [Time]Time to change from the starting duty to the stop duty.☞ P.4-64• Sweep Mode [SwpMode]
Select from continuous, single-shot, or gated single-shot.☞ P.4-65• Sweep function [SwpFctn]
Select from one-way/shuttle.☞ P.4-65

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4.7 Setting and Operation of Sweep
It is possible to set with center duty [Center] and span duty [Span], instead of start duty and stop
duty.☞ P.4-64
When sweep mode is single-shot or gated single-shot, it is necessary to set the trigger condition[Trig].☞ P.4-68
Set the following items as needed:• Marker duty[Marker] (the second page of the setting screen) ☞P.4-70• Stop level [StpLvl] (the third page of the setting screen) ☞P.4-67
The setting used for gated single-shot sweep only.
• Oscillation stop unit of gated single-shot sweep [OscStop] (the third page of the setting screen)☞ P.4-67
The setting used for gated single-shot sweep only.
• Sync output [SyncOut] (the third page of the setting screen) ☞ P.4-70

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4.8 Setting and Operation of Burst

4.8

Setting and Operation of Burst

4.8.1 Burst Oscillation Types
The following 4 types of burst oscillations are available.
• Auto Burst
Repeat oscillation and stop automatically at the specified by wave number respectively. A trigger
signal is not necessary.☞ P.4-84• Trigger Burst
Every time a trigger is accepted, perform oscillation specified wave number.☞ P.4-87• Gate Oscillation
While the gate is On, performs oscillation with integer half-cycle or half-cycle unit.☞ P.4-92• Triggered Gate Oscillation
Gate oscillation that turns the gate On/Off every time a trigger is accepted. ☞ P.4-97

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4.8 Setting and Operation of Burst

4.8.2 Auto Burst
Repeat oscillation and pause automatically at the specified by wave number respectively. A trigger
signal is not necessary.
Settings and operations are performed in the Oscillator setting screen. When you press the MENU
key while another screen is displayed, the Top menu is displayed. Press the [OSC] soft -key.
a) Auto burst example
Mark wave number (oscillation wave number): 3 waves, space wave number (stop oscillation
wave number): 2 waves, oscillation start/stop phase: 30 degree, stop level: Off.
Oscillation
start/stop phase30 degrees

Oscillation phase continues even during
stoppedMark wave
number 3

Space wave
number 2

Oscillation

Stopb) To set oscillation mode as auto burst
Press the MODE key, and then selectMODE key→Set the oscillation
mode of as burst(☞ P.4-23)[BURST] by using the soft-key to light"BURST" in the operation mode display
section on the front panel of the main unit.
This switches to burst oscillation mode.
There are total 2 pages of the setting
screens in the burst oscillation mode. You
can switch them by using the NEXT key.

Select [Auto]on the burst
mode setting
menu.

Then select burst mode [BrstMode] on thesecond page of the setting screen, andthen press the ENTER key. The selection
list appears in the soft-key area. When thesoft-key auto [Auto], auto burst is set.

c) Screen for auto burst setting◼ First page: Screen for basic parameter setting
These are common items independent from oscillation mode.
Indicates

that

the

first

page is displayed

Pressing the NEXT key
Setting of oscillation
start/stop phaseswitches the display to thesecond page.

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4.8 Setting and Operation of Burst◼ Second page: Screen for auto burst setting

Indicates that the second
page is displayed
Set the burst mode to[Auto]Mark wave number
Space wave number

Pressing the NEXT key

Stop levelswitches the display to theSync output

first page.

Mark wave number [Mark]The wave number of oscillation. This can be set in 0.5 cycle unit. Usually, set to 1 cycle unit.
Space wave number [Space]
The wave number to stop oscillation. This can be set in 0.5 cycle unit. Usually, set to 1 cycle
unit.
Stop level [StpLvl]
The signal level while oscillation is stopped. Set the level by specifying Off or On. Usually, set
to Off.☞ P.4-86
Sync output [SyncOut]
The output signal from a SYNC/SUB OUT terminal. Select from waveform reference phasesynchronization and burst synchronization.☞ P.4-86d) Waveform that auto is unavailable
Noise and DC cannot perform auto burst.
e) Setting items necessary for auto burst
Set the oscillation start/stop phase [Phase] on the first page of the setting screen.
Set mark wave number [Mark] and space wave number [Space] on the second page of thesetting screen.
Each wave number is usually set as integer value.
The stop level [StpLvl] on the second page of the setting screen is usually set as Off [Off].
☞ P. 4-90
f)

To start auto burst → Started automatically
In auto burst mode, burst starts automatically when entering in burst-oscillation mode. However,if the burst setting is not appropriate, the burst oscillation does not start ([Conflict] is displayed
at the top right of the screen). When pressing the soft-key [?] displayed on the left end, themessage concerning an improper setting appears. When that is changed to a proper setting, burst
oscillation starts.☞ P.12-9

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4.8 Setting and Operation of Burstg) To stop auto burst → Cannot
Oscillation cannot be stopped while in auto burst mode.
To stop oscillation, set the burst mode [BrstMode] as other than auto [Auto] on the second pageof the setting screen to prevent a trigger or gate signal from arriving.
To set as continues oscillation, change the oscillation mode to [CONT].
h) To output burst sync signal → In sync output setting
Set in the sync output [SyncOut] on the second page of the setting screen. Select from thefollowing two options:• Signal that synchronizes with reference phase of waveform [Sync]• Signal that synchronizes with burst oscillation [BrstSync]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from theSYNC/SUB OUT terminal.
◼ When [BrstSync] is selected,
Signals with TTL level that synchronize with the burst oscillation are output from theSYNC/SUB OUT terminal. It is low during oscillation, and high while oscillation is stopped,
as show in the following figure.
When a signal under burst is observed with the oscilloscope etc., it can be used as a trigger
signal.

Burst sync signal

Oscillation

StoppedOscillation

StoppedOutput signal

i)

How to use stop level
The level while oscillation is stopped is usually set by oscillation start/stop phase. It is also
possible to set by the ratio to the full scale of the amplitude independently.
Set the stop level [StpLvl] as On [On] on the second page of the setting screen, and set the levelwith % value.☞ P.4-90

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4.8 Setting and Operation of Burst

4.8.3 Trigger burst
Every time a trigger is accepted, perform oscillation with the specified wave number.
Settings and operations are performed in the OSC setting screen. When you press the MENU key while
another screen is displayed, the Top menu is displayed. Press the [OSC] soft-key.
a) Trigger burst example
Mark wave number (oscillation wave number): 4 waves, oscillation start/stop phase: 30 degree,
stop level: Off.

Trigger signal

Oscillation
start/stop phase30 degrees

Output signal

Triggerdelay time

Triggerdelay time

No new trigger is accepted
during this intervalb) To set oscillation mode as trigger burst
Press the MODE key, and then selectMODE key→Set the oscillation
mode of as burst(☞ P.4-23)[BURST] by using the soft-key to light"BURST" in the operation mode display
section on the front panel of the main unit.
This switches to burst oscillation mode.
There are total 2 pages of the setting
screens in the burst oscillation mode. You
can switch them by using the NEXT key.
Then select burst mode [BrstMode] on thesecond page of the setting screen, and thenpress the ENTER key. The selection list
appears in the soft-key area. When thesoft-key trigger burst [Trigger] is pressed,
trigger burst is set.

Select [Trigger] on
the burst modesetting menu.

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4.8 Setting and Operation of Burstc) Screen for trigger burst setting◼ First page: Screen for basic parameter setting
These are common items independent from oscillation mode.
Indicates that the firstpage is displayed

Setting of oscillation
start/stop phase

Pressing the NEXT key
switches the display tothe second page.

◼ Second page: Screen for trigger burst setting

Indicates that the second
page is displayed
Set the burst mode to [Trigger]

Mark wave
numberTrigger delay

Stop level

Pressing the NEXT key
Triggerswitches the display to

Sync output

the first page.

Oscillation start/stop phase [Phase]
The phase to start/stop oscillation.
Mark wave number [Mark]The wave number oscillating every time a trigger is accepted. This can be set in 0.5 cycle
unit.
Stop level [StpLvl]
The signal level while oscillation is stopped. Set the level to turn on or turn off. Usually, set
to Off.☞ P.4-90
Trigger [Trig]
The trigger condition. Select as a trigger source from the internal or external.☞ P.4-89
Trigger delay [TrigDly]
Trigger delay time. Start oscillation when the specified time elapses after accepting a trigger.
☞ P.4-89
Sync output [SyncOut]
The output signal from a sync/sub-output terminal. Select from waveform reference phasesynchronization and burst synchronization.☞ P.4-90d) Waveform that trigger is unavailable
Noise and DC cannot perform trigger burst.

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4.8 Setting and Operation of Burste) Setting items necessary for trigger burst
Set the oscillation start/stop phase [Phase] on the first page of the setting screen.
Set mark wave number [Mark] on the second page of the setting screen. Usually set as integer
value.
The stop level [StpLvl] on the second page of the setting screen is usually set as Off [Off].
☞ P.4-90
A trigger is necessary for trigger burst. See the next section.
f)

Trigger setting for trigger burst
Internal trigger oscillator, external signal, manual trigger key operation, and remote trigger canbe used as a trigger.
When a trigger is accepted, the TRIG'D lamp on the TRIG key illuminates.
Set the trigger source in the trigger [Trig] on the second page of the setting screen◼ Trigger source setting
A trigger source can be selected from internal [Int] or external [Ext].
When a trigger source is internal [Int], a trigger period can be set.
When a trigger source is external [Ext], the polarity of a trigger can be set.
When a trigger source is external [Ext], enter a trigger signal with TTL level to the external
trigger input terminal (TRIG IN).
◼ How to use manual and remote triggers
Manual trigger operation and remote trigger operation is effective, regardless of the trigger
source setting.
The TRIG key can be used for manual trigger operation.
However, in case of WF1948, the TRIG key only works on the channel side where display isactive. For the channel where display is active, ☞ P.4-18.
When only manual trigger operation and remote trigger operation are used for a trigger, set thetrigger source as external [Ext]. Moreover, we will recommend that the polarity is set as [Off] to
avoid malfunctions caused by noise.
◼ Trigger delay setting
Set the trigger delay time in the trigger delay [TrigDly] on the second page of the setting screen .
Start oscillation when the specified time elapses after accepting a trigger. The setting of trigger
delay time is effective for all trigger sources.
The delay inside the equipment is minimized when the trigger delay time is set as zero, however,there is a delay in the waveform actually output.☞ P.15-12
A new trigger is not accepted until oscillation of the specified number of mark waves completes.

g) To start trigger burst → With trigger
When a trigger is accepted, start oscillation with the specified wave number.
Internal trigger oscillator, external signal, manual trigger operation, and remote trigger can beused as a trigger.
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4.8 Setting and Operation of Bursth) To output burst sync signal → In sync output setting
Set in the sync output [SyncOut] on the second page of the setting screen. Select from thefollowing two options:• Signal that synchronizes with reference phase of waveform [Sync]• Signal that synchronizes with burst oscillation [BrstSync]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from theSYNC/SUB OUT terminal.
◼ When [BrstSync] is selected,
Signals with TTL level that synchronize with the burst oscillation are output f rom theSYNC/SUB OUT terminal. It is low during oscillation, and high while oscillation is stopped, asshow in the following figure.
When a signal under burst is observed with the oscilloscope etc., it can be used as a trigger
signal.
Burst sync signal

Oscillation

StoppedOscillation

StoppedOutput signal

i)

How to use stop level
The level while oscillation is stopped is usually set by oscillation start/stop phase. It is also
possible to set by the ratio to the full scale of the amplitude independently.
Set the stop level [StpLvl] as On [On] on the second page of the setting screen, and set the levelwith % value.
The example in the following figure is for mark wave number, : 3 waves, oscillation start/stop
phase: 30 degree, stop level: OFF and ON with -50%. Note that oscillation start/stop phase isstill effective.
Oscillation start/stop phase 30 degrees

Stop level OFF

Oscillation start/stop phase 30 degrees

Stop level -50%

Stop level ON

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4.8 Setting and Operation of Burst

When you the stop level is applied to the square wave, a square wave with three values can be
output as shown in the following figure.
In the example of the figure, the stop level is set as 0%, oscillation start/stop phase are set as
0°(both the standard and enhanced duty variable ranges are available). If the stop level is notapplied, the level of square wave while oscillation is stopped is always either of low level orhigh level.

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4.8 Setting and Operation of Burst

4.8.4 Gate Oscillation
While the gate is On, performs oscillation with integer half-cycle or half-cycle unit. Settings andoperations are performed in the Oscillator setting screen. When you press the MENU key while
another screen is displayed, the Top menu is displayed. Press the [OSC] soft -key.
a) Gate oscillation example
Oscillation start/stop phase: 30 degree, oscillation stop unit: 1 cycle, stop level: Off. The
oscillation is stopped when reaching the oscillation start/stop phase after the gate signal is Off.
Gate signal

Gate onGate off

Gate onGate off

Output signal

Oscillation start/stop
phase 30 degreesb) To set oscillation mode as gate oscillation
MODE key→Set the oscillation
mode of as burst(☞ P.4-23)

Select [Gate]on the burst
mode setting
menu.

Press the MODE key, and then select[BURST] by using the soft-key to light"BURST" in the operation mode display
section on the front panel of the main unit.
This switches to burst oscillation mode.
There are total 2 pages of the setting
screens in the burst oscillation mode. You
can switch them by using the NEXT key.
Then select burst mode [BrstMode] on thesecond page of the setting screen, and thenpress the ENTER key. The selection list
appears in the soft-key area. When thesoft-key gate [Gage], gate oscillation is set.

c) Screen for gate oscillation setting◼ First page: Screen for basic parameter setting
These are common items independent from oscillation mode.
Indicates that the firstpage is displayed

Pressing the NEXT key
Setting ofoscillation
start/stop phaseswitches the display tothe second page.

Oscillation start/stop phase [Phase]

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4.8 Setting and Operation of Burst
The phase to start/stop oscillation.

◼ Second page: Screen for gate oscillation setting

Indicates that the second
page is displayed

Set the burst mode to[Gate]
Stop level
TriggerPressing the NEXT key

Oscillation stop unit

switches the display to the

Synchronization
outputfirst page.

Stop level [StpLvl]
The signal level while oscillation is stopped. Set the level to turn on or turn off. Usually, set
to Off.☞ P.4-95
Trigger [Trig]
The trigger condition (gate condition). Select as a trigger source from the internal or external.
☞ P.4-94
Oscillation Stop Unit [OscStop]
The oscillation stop unit. Select from 1 cycle and half period. Usually, set to 1 cycle .
☞ P.4-95
Synchronization output [SyncOut]
The output signal from a SYNC/SUB OUT terminal. Select from waveform reference phasesynchronization and burst synchronization.☞ P.4-94d) Waveform that gate oscillation is unavailable
DC cannot perform gate oscillation. Noise can perform gate oscillation, however, the action
differs from other waveforms.☞ P.4-96e) Setting items necessary for gate oscillation
Set the oscillation start/stop phase [Phase] on the first page of the setting screen.
The stop level [StpLvl] on the second page of the setting screen is usually set as Off [Off].
☞ P.4-95
The oscillation stop unit [OscStop] on the second page of the setting screen is usually set as 1
cycle [Cycle].☞ P.4-95
A trigger (gate) is necessary for gate oscillation. See the next section.
f)

Trigger (gate) setting for gate oscillation
Internal trigger oscillator, external signal, manual trigger operation, and remote trigger can beused as a trigger (gate).
While a gate signal is On, the TRIG'D lamp on the TRIG key illuminates.
Set the trigger source in the trigger [Trig] on the second page of the setting screen The trigger
delay is fixed to the minimum value.

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4.8 Setting and Operation of Burst◼Trigger source setting
A trigger source can be selected from internal [Int] or external [Ext].
When a trigger source is internal [Int], a trigger period can be set. At this time, the gate signal issquare waves with duty 50%.
When a trigger source is external [Ext], the polarity of a trigger can be set.
◼How to use manual and remote triggers
Manual trigger operation and remote trigger operation is effective, regardless of the trigger
source setting.
The TRIG key can be used for manual trigger operation.
While the TRIG key is pressed, the gate signal is On. However, in case of WF1948,
the TRIG key works for the channel whose display is active.
For the channel where display is active, ☞ P.4-18.
When only manual trigger operation and remote trigger operation are used for a trigger, set thetrigger source as external [Ext]. Moreover, we will recommend that the polarity is set as [Off] to
avoid malfunctions caused by noise.
g) To start gate oscillation → With trigger (gate signal)
When gate signal On is accepted, oscillation starts.
Internal trigger oscillator, external signal, manual trigger operation, and remote trigger can beused as a trigger.
h) To output burst sync signal → In sync output setting
Set in the sync output [SyncOut] on the second page of the setting screen. Select from thefollowing two options:• Signal that synchronizes with reference phase of waveform [Sync]• Signal that synchronizes with burst oscillation [BrstSync]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from theSYNC/SUB OUT terminal.
◼ When [BrstSync] is selected,
Signals with TTL level that synchronize with the gate oscillation are output from theSYNC/SUB OUT terminal. It is low during oscillation, and high while oscillation is stopped, asshow in the following figure. Note that it is different from a gate signal.
When a signal under burst is observed with the oscilloscope etc., it can be used as a trigger
signal.
Gate signal

Burst sync signal

Gate on

Oscillation

Gate off

StoppedGate on

Oscillation

Gate off

StoppedOutput signal

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4.8 Setting and Operation of Bursti)

To oscillate in half cycle → Oscillation stop unit as half cycle
When you want to stop oscillation every half cycle, set the oscillation stop unit [OscStop] ashalf cycle [HalfCycle] on the second page of the setting screen. Usually, set to 1 cycle [Cycle].
When it is set as 1 cycle [Cycle], it is oscillation with integer cycle.
The following figure shows the comparison for the cases of one cycle and half cycle. Oscillation
start/stop phase: 30 degree, stop level: OFF.
In case of 1 cycle unit, the oscillation is stopped when reaching to the oscillation start/stop
phase after gate is Off.
In case of half cycle unit, the oscillation is stopped when reaching to the oscillation start/stop
phase or the oscillation start/stop phase + 180 degree (or –180 degree) after gate is Off, and thenit transits to oscillation start/stop phase.
Gate onGate off

Gate onGate off

Gate signal

Oscillation in
1-cycle unit
Oscillation
start/stop phase30 degrees

Oscillation
stops at 210
degrees

Oscillation in
half-cycle unitj)

How to use stop level
The level while oscillation is stopped is usually set by oscillation start/stop phase. It is also
possible to set by the ratio to the full scale of the amplitude independently.
Set the stop level [StpLvl] as On [On] on the second page of the setting screen, and set the levelwith % value.☞ P.4-90

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4.8 Setting and Operation of Burstk) Noise gate oscillation
Because noise has no cycle, the gate On zone is the oscillation zone directly, and the gate Offzone is the oscillation zone directly. In addition, because noise has no phase, a stop level set tingis always effective.
The following figure shows the example of noise gate oscillation. That is the case with stoplevel of 0%.

Gate signal

Burst sync signal

Gate onGate off

Gate on

Oscillation

StoppedOscillation

Output signal

Stop level 0%

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4.8 Setting and Operation of Burst

4.8.5 Triggered Gate Oscillation
Gate oscillation that turns the gate On/Off every time a trigger is accepted.
Settings and operations are performed in the Oscillator setting screen. When you press the MENU
key while another screen is displayed, the Top menu is displayed. Press the [OSC] soft -key.
a) Triggered gate oscillation example
Oscillation start/stop phase: 30 degree, oscillation stop unit: 1 cycle, stop level: Off.
The oscillation is stopped when reaching the oscillation start/stop phase after the gate signal is
Off.
Trigger signal

Internal gate signal

Gate onGate off

Gate onGate off

Output signal

Oscillation start/stop
phase 30 degreesb) To set oscillation mode as triggered gate oscillation
MODE key→Set the oscillation modeof as burst(☞ P.4-23)

Press the MODE key, and then select[BURST] by using the soft-key to light"BURST" in the operation mode display
section on the front panel of the main unit.
This switches to burst oscillation mode.
There are total 2 pages of the setting
screens in the burst oscillation mode. You
can switch them by using the NEXT key.
Then, select the burst mode [BrstMode]on the second page of the burst modesetting screen, and then press the Enter key.
The selection list is displayed in the soft-key
area. When the soft-key triggered gateoscillation [TrigGate] is pressed, triggered
gate oscillation is set.

Select [TrigGate]on the burst
mode setting
menu.

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4.8 Setting and Operation of Burstc) Screen for triggered gate oscillation setting◼ First page: Screen for basic parameter setting
These are common items independent from oscillation mode.
Indicates that the first pageis displayed

Setting of oscillation
start/stop phase

Pressing the NEXT key
switches the display tothe second page.

Oscillation start/stop phase [Phase]
The phase to start/stop oscillation.
◼ Second page: Screen for triggered gate oscillation setting
Indicates that the second
page is displayed

Set the burst mode to[TrigGate]

Stop level
TriggerPressing the NEXT key
switches the display to thefirst page.

Oscillation stop unit
Synchronization output

Stop level [StpLvl]
The signal level while oscillation is stopped. Set the level to turn on or turn off. Usually, set
to Off.☞ P.4-100
Trigger [Trig]
The trigger condition.
Select as a trigger source from the internal or external.☞ P.4-99
Oscillation Stop Unit [OscStop]
The oscillation stop unit. Select from 1 cycle unit and half period unit. Usually, set to 1 cycle
unit.☞ P.4-100
Synchronization output [SyncOut]
The output signal from a SYNC/SUB OUT terminal. Select from waveform reference phasesynchronization and burst synchronization.☞ P.4-99d) Waveform that trigger gate oscillation is unavailable
DC cannot perform triggered gate oscillation.
Noise can perform triggered gate oscillation, however, the action differs from other waveforms.
☞ P.4-100

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4.8 Setting and Operation of Burste) Setting items necessary for triggered gate oscillation
Set the oscillation start/stop phase [Phase] on the first page of the setting screen.
The stop level [StpLvl] on the second page of the setting screen is usually set as Off [Off].
☞ P.4-100
The oscillation stop unit [OscStop] on the second page of the setting screen is usually set as 1
cycle [Cycle].☞ P.4-100
A trigger is necessary for triggered gate oscillation. See the next section.
f)

Trigger setting of triggered gate oscillation
Internal trigger oscillator, external signal, manual trigger key operation, and remote trigger canbe used as a trigger.
When a trigger is accepted, the TRIG'D lamp on the TRIG key illuminates.
Set the trigger source in the trigger [Trig] on the second page of the setting screen The trigger
delay is fixed to the minimum value.
◼ Trigger source setting
A trigger source can be selected from internal [Int] or external [Ext].
When a trigger source is internal [Int], a trigger period can be set.
When a trigger source is external [Ext], the polarity of a trigger can be set.
When a trigger source is external [Ext], enter a trigger signal with TTL level to the external
trigger input terminal (TRIG IN).
◼ How to use manual and remote triggers
Manual trigger operation and remote trigger operation is effective, regardless of the trigger
source setting.
The TRIG key can be used for manual trigger operation.
However, in case of WF1948, the TRIG key only works on the channel side where display isactive. For the channel where display is active, ☞ P.4-18.
When only manual trigger operation and remote trigger operation are used for a trigger, set thetrigger source as external [Ext]. Moreover, we will recommend that the polarity is set as [Off] to
avoid malfunctions caused by noise.

g) To start triggered gate oscillation → With trigger
When the trigger is accepted and the internal gate signal is On, oscillation starts.
Internal trigger oscillator, external signal, manual trigger operation, and remote trigger can beused as a trigger.
h) To output burst sync signal → In sync output setting
Set in the sync output [SyncOut] on the second page of the setting screen. Select from thefollowing two options:•Signal that synchronizes with reference phase of waveform [Sync]

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4.8 Setting and Operation of Burst•Signal that synchronizes with burst oscillation [BrstSync]◼ When [Sync] is selected,
Signals with TTL level that are rising at the reference phase of waveform are output from theSYNC/SUB OUT terminal.

◼ When [BrstSync] is selected,
Signals with TTL level that synchronize with the gate oscillation are output fr om theSYNC/SUB OUT terminal. It is low during oscillation, and high while oscillation is stopped, asshow in the following figure. Note that it is different from a gate signal.
When a signal under burst is observed with the oscilloscope etc., it can be us ed as a trigger
signal.
Trigger signal

Internal gate signal

Gate onBurst sync signal

Oscillation

Gate off

StoppedGate onGate off

Oscillation

StoppedOutput signal

i)

To oscillate in half cycle → Oscillation stop unit as half cycle
When you want to stop oscillation every half cycle, set the oscillation stop unit [OscStop] ashalf cycle [HalfCycle] on the second page of the setting screen. Usually, set to 1 cycle [Cycle].
When it is set as 1 cycle [Cycle], it is oscillation with integer cycle.

j)

How to use stop level
The level while oscillation is stopped is usually set by oscillation start/stop phase. It is also
possible to set by the ratio to the full scale of the amplitude independently.
Set the stop level [StpLvl] as On [On] on the second page of the setting screen, and set the levelwith % value.☞ P.4-90k) Trigger gate oscillation of noise
Because noise has no cycle, the gate On zone is the oscillation zone, and the gate Off zone is theoscillation zone. In addition, because noise has no phase, a stop level setting is always effective.
☞ P.4-96

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5. Saving and Recalling Settings

5.1

Procedure to Save Settings ..................................................................................... 5-2

5.2

Procedure to Recall Settings .................................................................................. 5-3

5.3

Restoring Saved Contents to Initial Settings ........................................................ 5-4

5.4

Changing Setting Memory Name ........................................................................... 5-4

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5.1 Procedure to Save Settings
You can save the current setting condition in the setting memory, and recall it to use later.
You can make operations to save the setting and recall it in the Memory screen.

The setting memory 1 is used to startup after power failure. ☞ P.4-5
Factory defaults are saved in all the setting memories at factory shipment.

5.1

Procedure to Save Settings
1. When you press the MENU key, the top
menu is displayed in the soft-key area.
Then, press the [MEMORY] soft-key. This
opens the Memory screen.

2. In the Memory screen, select [Memory

In the top menu, select[MEMORY]No.] field on the top right of the screen,
and then press the ENTER key to open
the input field of the setting memory
number to save

Select [Memory No.] on the top right of the screen, andthen press the ENTER key to open the input field of thesetting memory number to save

3. Use the up/down arrow key or the modify
The overview
of the settingin thespecifiedsettingmemorynumber isdisplayed

The specified setting memory number and the setting nameare highlighted

knob to increment or decrement thesetting memory number.
In the left side of the screen, the specified
setting memory number and its setting
name are highlighted. In the right side of
the screen, the overview of the setting
saved in the specified setting memory
number is displayed.

4. Select a setting memory number to save,and then press the ENTER key to close
the input field of the setting memory
number.

5. Press the [Store] soft-key to open thePress the [Store]
soft-key to open the
dialog box to confirm
the save operation.

Select [OK], and thenpress the ENTER key
to make a savedialog box to confirm the save operation.
If you want to make a save, select [OK],and then press the ENTER key. The saveis made and the setting saved previously
in the setting memory number isoverwritten by the new setting

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5.2 Procedure to Recall Settings

5.2

Procedure to Recall Settings

1. When you press the MENU key,

the top menu is displayed in thesoft-key area. Then, press the[MEMORY] soft-key. This opens
the Memory screen.
2. In the Recall Memory screen,
select [Memory No.] field on the
top right of the screen, and thenpress the ENTER key to open the
input field of the setting memory
number to recall
In the top menu, select[MEMORY]
3. Use the up/down arrow key or themodify knob to increment or
Select [Memory No.] on the top right of the screen, andthen press the ENTER key to open the input field of thedecrement the setting memory
setting memory number to savenumber. In the left end of thescreen, the specified setting
The overview of thememory number and its setting
setting in thename are highlighted. In the rightspecified setting
memory number isside of the screen, the overview
displayedof the setting saved in thespecified setting memory number
is displayed.
4. Select a setting memory number
to recall, and then press the
ENTER key to close the input
The specified setting memory number and the setting nameare highlighted
field of the setting memory.
Press the [Recall] 5. Press the [Recall] soft-key tosoft-key to open the
open the dialog box to confirm
dialog box to confirm
the recall operation.
the recall operation
If you want to make a recall,select [OK], and then press the
Select [OK], and thenpress the ENTER key
ENTER key. The recall is made,to make a recall
and then the current setting ischanged.

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5.3 Restoring Saved Contents to Initial Settings

5.3

Restoring Saved Contents to Initial Settings
Press the [Clear]soft-key to open the
dialog box to confirm
the initialization
operation.
Select [OK], and thenpress the ENTER key
to reset the setting to
the initial setting

5.4

As with the save operation, after
setting the setting memory number,press the [Clear] soft-key. The dialog
box to confirm the initialization
operation is opened.
If you want to make an initialization,
select [OK], and then press the
ENTER key. The setting saved
previously in the setting memory
number is overwritten by the initial
setting.

Changing Setting Memory Name
Press the [Rename]soft-key to open the
input field of the setting
memory name

1. As with the save operation, after
setting the setting memory
number, press the [Rename]soft-key.
The input field of the setting
memory name is opened.

2. Select the digit to be changed by using the right or left arrow key, and then use the3.

up or down arrow key/the modify knob to change the character. You can enter
uppercase and lowercase alphabetic characters, numbers, and symbols. You candirectly enter numbers using the numeric keypad.
Press the [Delete] soft-key to delete a character at the cursor position and shift astring at the right side of the cursor to the left by one character.
Press the [Insert] soft-key to insert a space at the cursor position.
Press the [CLR =>] soft-key to delete a string at the right side (excluding the
cursor position) of the cursor.
Press the [Clear] soft-key to clear all characters.
The maximum number of characters of a name can be 20.
Press the [Apply] soft-key or the ENTER key to fix the changed name and close theinput field of the setting memory name.
Press the CANCEL key to leave the name as it is and close the input field of thesetting memory name.

Also you can change a setting memory name in the Recall Memory screen.

Check
You can use the following characters for a setting memory name:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
0123456789!#$%&’()*+,-./:;<=>?@[]¥^_`{|}~
Space

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6.

Creating Arbitrary Waveforms

6.1

Basics ...................................................................................................................... 6-2

6.2

Display Procedure and Overview of Screen for Creating/Editing Arbitrary

Waveforms ......................................................................................................................... 6-4
6.3

Creating New Arbitrary Waveform ........................................................................ 6-6

6.4

Simple Arbitrary Waveform Creating Example .................................................... 6-7

6.5

Outputting Created Arbitrary Waveform .............................................................. 6-8

6.6

Saving Created Arbitrary Waveform ..................................................................... 6-8

6.7

Identifying Memory Space Required for Saving Arbitrary Waveforms ................ 6-9

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6.1 Basics

6.1

BasicsThere are the following two types of methods to create arbitrary waveforms:• Use the accompanying arbitrary waveform editing software to create arbitrary waveforms on a P C.
• Enter waveform data on a panel.
This section describes the method to create arbitrary waveforms using operations on the panel of themain unit.
Before doing it, you must understand some of arbitrary waveforms of this product.
◼ Two types of data formats
There are the following two types of data formats for the arbitrary waveform data of this product:• Array format
Data array itself corresponding to the address of a waveform memory.
Waveforms imported by the digital oscilloscope are used as arbitrary waveforms as they are.
Waveforms imported by the digital oscilloscope can be transferred to this product using theaccompanying arbitrary waveform editing software.
Array format data cannot be created/edited on the panel.
Waveform length of the array format is 4 K- to 512 K-word (2n, n = 12 to 19).
• Control point format
A waveform is created by interpolating between the specified control points (control points)
with a straight line.
Data value for each memory address cannot be specified directly.
A relatively simple arbitrary waveform can be created/edited manually on the panel.
The number of control points in the control point format can be 2 to 10,000 points.
For a waveform to be created, its time axis direction is fixed to 0 to 1 per a cycle and th e
amplitude direction is fixed to ± 1 (equivalent to ± FS of a waveform memory).
◼ Save location of arbitrary waveforms
There are the following two save locations of arbitrary waveform data (separately from the 512
K-word length output waveform memory): Each memory shares two channels for WF1948.
• Save memory
Non-volatile memory to save arbitrary waveforms.
The non-volatile memory can save arbitrary waveforms up to 128-waveform or 4 M-word (8192
K-byte).
It can save arbitrary waveform data in any of array and control point formats.
For memory capacity required for save, ☞ P.6-9• Edit memory
Volatile memory to create an arbitrary waveform in the control point format. You can change
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6.1 Basics
the number of control points between 2 and 10,000 points.
When you create/edit an arbitrary waveform on the panel, you operate data on this edit memory.
Only one waveform can be treated on the edit memory.

◼ Selection of arbitrary waveforms to be output
If you select an arbitrary waveform as an output waveform in the Oscillator setting screen, you c an
select an output wave of all the saved arbitrary waveforms. You can select any of waveforms savedin the above save memory or a waveform on the edit memory.
The selected waveform is written to the output waveform memory of the maximum 512 K -wordlength.
If you select an output waveform on the edit memory, a waveform you are creating/editing appears
as it is in the output.

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6.2 Display Procedure and Overview of Screen for Creating/Editing Arbitrary Waveforms

6.2 Display Procedure and Overview of Screen for Creating/Editing
Arbitrary Waveforms
An arbitrary waveform is created/edited in the ARB Edit screen.

1. Press the MEMU key to show the

Select [ARB
EDIT].

soft-keys at the bottom of the screen.
Then, select the [ARB EDIT]
soft-key. This opens the ARB Edit
screen.

2. The ARB Edit screen has two types of display formats.
They are a list display, which displays values side by side, and graph display.
You can switch a display between them using tabs at the top left end of thescreen.
[Index] shows numbers of control points, beginning with zero (0). Start point isfixed to X = 0.000000. End point is fixed to X = 1.000000, and the paired Y
values of both the start and end points are the same (the same point).
If an output waveform is set to the arbitrary waveform on the edit memory, awaveform in process of creation appears as it is in the output. If the outpu t
waveform is set to other waveform, when you select the [Apply] button andpress the ENTER key, the setting of output waveform is changed to the arbitrary
waveform on the edit memory, and a waveform in process of creation appears in
the output.

◼List display
For the list display, a waveform in process of creation and a list of control points are displayed.
A shape of waveform is created by setting X and Y values for each control point.
Waveform inprocess ofcreation

Waveform output
buttons
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6.2 Display Procedure and Overview of Screen for Creating/Editing Arbitrary Waveforms◼ Graph display
For the graph display, a waveform in process of creation is enlarged. X and Y values of the selected one
control point are displayed.
As with the list display, a shape of waveform is created by setting X and Y values for each control
point.
You can enlarge a waveform display both horizontally and vertically with a focus on the selected
control point.

[Index] of thecontrol point

Waveform
outputbuttons

X and Y values of
selected control
point

Zoom in/out the
waveform display
vertically

Selected
control point

Zoom in/out the
waveform display
horizontally

Waveform inprocess ofcreation◼ Soft-keys
First row ([  1/2] appears to the right end)[New]: Clears the edit memory and makes it an initial state.
[WF Copy]: Copies a standard waveform onto the edit memory.
[Recall]: Copies the already saved arbitrary waveform in the control point fo rmat onto theedit memory.
[Store]: Saves a waveform on the edit memory.
Second row ([  2/2] appears to the right end)
[Index -1]: Decrements a value of [Index] by one (1)[Index +1]: Increments a value of [Index] by one (1)[Delete]: Deletes the selected control point.
[Insert]: Inserts a new control point at the center of between the selected control point and thecontrol point just before the selected point

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WF1947/WF1948

6.3 Creating New Arbitrary Waveform

6.3

Creating New Arbitrary Waveform

There are the following three types of methods to newly create an arbitrary waveform:• Create a new arbitrary waveform thoroughlyFirst, press the [New] soft-key to clear the edit memory. Then, enter control points. The next
section describes the example of creation.
• Based on the standard waveform, modify it to create a new arbitrary waveform
First, press the [WF Copy] soft-key to copy a standard waveform to the edit memory. Then,
modify control points. How to operate control points is the same as the case of creating a newarbitrary waveform thoroughly.
However, noise and DC of the standard waveform cannot be copied. Square and pulse waves
are copied as ideal square waves that keep duty.
• Based on the saved arbitrary waveform, modify it to create a new arbitrary waveform
First, press the [Recall] soft-key to copy the saved arbitrary waveform in the control point
format onto the edit memory. Then, modify control points. How to operate control points isthe same as the case of creating a new arbitrary waveform thoroughly.

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WF1947/WF1948

6.4 Simple Arbitrary Waveform Creating Example

6.4

Simple Arbitrary Waveform Creating Example

This section creates a simple arbitrary waveform actually. Use the list display to explain the example.
Arbitrary waveform to create is a triangular wave as shown below. The number of control points ofthis waveform are three points, but in this section, it begins with two points and then changes to threepoints on the way.

When you press the soft-key [Index] and set the number of control points to 2, it will be thefollowing settings.

Change the setting of Index=1 to X=0.25 and Y=+1.

Select the Y-value field at the end line (Index=2, X=1) and press soft-key [Insert]. A newcontrol point of X=0.625000, Y=+0.49998 is created. A Y value is rounded to 16 -bit
resolution which ±32767 is ±1.

Change the setting of Index=2 to X=0.25 and Y=-1. Now it is finished.

Check• A X value can be changed within a range between the control point justbefore the X value and the control point just after the X value.
• A Y value is rounded to 16-bit resolution.
• If you change a Y value to the form of a step, set the variation width
between adjacent X values to the minimum value, 0.000001.

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WF1947/WF1948

6.5 Outputting Created Arbitrary Waveform

6.5

Outputting Created Arbitrary Waveform

Select the [Apply] button (by CH for WF1948) on the screen, and then press the ENTER key.
The setting of output waveform is changed to the arbitrary waveform on the edit memory, and a
waveform in process of creation appears in the output.
If an output waveform is set to the arbitrary waveform on the edit memory, a waveform in process ofcreation appears as it is in the output.

6.6

Saving Created Arbitrary Waveform

Press the [Store] soft-key to open a window to save. Select a memory number between 1 to 128 tooperate a save. You can name a waveform.

6-8

WF1947/WF1948

6.7 Identifying Memory Space Required for Saving Arbitrary Waveforms

6.7 Identifying Memory Space Required for Saving Arbitrary
Waveforms
The non-volatile memory can save arbitrary waveforms up to 128-waveform or 4 M-word (8192
K-byte).
The memory capacity (K-byte) required when saving an arbitrary waveform in the array format andcontrol point format, respectively is calculated by the following formula:
Array format: (2 x waveform length (word) + 768) / 1024 (rounding up the fractional part)
Control point format: (8 x the number of control points + 768) / 1024 (rounding up the fractionalpart)
The memory capacity required when saving an arbitrary waveform in the array format is shown in
the following table:
Waveform size

4KW

8KW

16KW

32KW

64KW

128KW

256KW

512KW

Memory capacity
required for save

9KB

17KB

33KB

65KB

129KB

257KB

513KB

1025KBThe example of memory capacity required when saving an arbitrary waveform in the control point
format is shown in the following table:
Number of control
pointsMemory capacity
required for save

2

10

100

300

1,000

2,000

5,000

10,000

1KB

1KB

2KB

4KB

9KB

17KB

40KB

79KB

In the selection screen of the arbitrary waveform (common to both the recall and save), the following
items are displayed in addition to the waveform number, [No.], and waveform name, [Name]:• Data format [Type]: The waveforms in the array and control point formats are displayed as[RAW] and [Point], respectively. The edit memory with No.0 is displayed as [Point] because of
the control point format.
• Save memory capacity [Size]: For arbitrary waveforms between No.1 to 128, memory capacity
used for save is displayed in K-byte. For the edit memory with No.0, memory capacity required
if it is saved is displayed in K-byte.
• Total save memory capacity [Total Size]: Total memory capacity currently used for save ofarbitrary waveforms between No.1 to 128 is displayed in K-byte. The size of edit memory with
No.0 is excluded from the total capacity.

Memory capacity used forsaveData format

Total memory capacity
used for save

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6.7 Identifying Memory Space Required for Saving Arbitrary Waveforms
MEMO

6-10

WF1947/WF1948

7. Convenient Use of 2-channel Equipment (WF1948 Only)

7.1

Overview ................................................................................................................. 7-2

7.2

Copying Setting between Channels ....................................................................... 7-3

7.3

Unifying Settings of 2 Channels ............................................................................ 7-5

7.4

Phase Synchronization between Channels ............................................................ 7-6

7.5

Maintaining Both Channels to Same Frequency (2-Channel Coordination,

2-Phase) ............................................................................................................................. 7-7
7.6

Keeping Frequency Difference Constant (2-Channel Coordination, 2-Tone) ....... 7-9

7.7

Keeping Frequency Ratio Constant (2-Channel Coordination, Ratio) ................ 7-11

7.8

Obtaining Differential Output (2-Channel Coordination, Differential) .............. 7-13

7-1

WF1947/WF1948

7.1 Overview

7.1

Overview

You can use 2-channel equipment, WF1948, not only as the two independent oscillators but also as
the 2-channel coordination setting and operation.
Functions specific to 2-channel equipment are as follows:• Parameter copy function
One's channel setting can be copied to another's channel setting.
Channel settings can be changed each other.☞ P.7-3• 2-channel equivalence setting function
Various values such as the amplitude and DC offset can be set to the same values between two
channels. Output on/off can be operated simultaneously between two channels. ☞ P.7-5• Phase synchronization function
Oscillation phase for each channel can be initialized. This function is used for 2 -channel
independent operation with the continuous oscillation mode.☞ P.7-6• 2-channel coordination operation: 2-phase function
The synchronization relationship with the same frequency can be kept. This function controls tokeep the synchronization relationship with the same frequency also during the frequency
modulation or frequency sweep.☞ P.7-7• 2-channel coordination operation: function with constant frequency difference
The frequency can be changed with the frequency difference kept constant. This function controls
to keep the frequency difference constant also during the frequency modulation or frequency
sweep.☞ P.7-9• 2-channel coordination operation: function with constant frequency ratio
The frequency can be changed with both the frequency ratio and synchronization relationship kept
constant. This function controls to keep the frequency ratio constant also during the frequency
modulation or frequency sweep.☞ P.7-11• 2-channel coordination operation: differential output function
The reverse phase waveform can be output with the same frequency, amplitude, and DC offset.
This function controls to keep the reverse phase waveform also during the frequency modulation
or frequency sweep.☞ P.7-13

7-2

WF1947/WF1948

7.2 Copying Setting between Channels

7.2

Copying Setting between Channels

Copying the settings between channels can be done on the Utility screen.

1. Select [Parameter Copy] on the Utility

In the Utility
screen, select[Parameter
Copy], and thenpress theENTER key

screen, and then press the ENTER
key.

The Parametercopy window is
opened

2. After the Parameter copy window is

Select a copy
direction

opened, select the [Copy Direction]
field, and then press the ENTER key.
The selection list to show the copy
direction is opened.
You can select a copy direction from thefollowing three types: [CH1→CH2] (CH1
to CH2 ), [CH2→CH1] (CH2 to CH1),and [CH1→CH2] (exchange with eachother between CH1 and CH2).
Select a direction you want, and thenpress the ENTER key.

3. Next, select a parameter type to copy.

If you copy all parameters, select [All Parameters]. Otherwise, select parameters foreach oscillation mode. There are the following four types of parameters as
parameters for each oscillation modes: continuous oscillation mode parameters,[Basic Parameters], modulated oscillation mode parameters, [Modulation
Parameters], sweep oscillation mode parameters, [Sweep Parameters], and burst
oscillation mode parameters [Burst Parameters].
Select a parameter type you want and press the ENTER key, then the parameter
type is set as the copy target and [Copy] is shown next to it. Press the ENTER key
again, then the parameter type is excluded from the copy target and [Off] is shown
next to it.
Copy the modulation andburst parameters

Copy allparameters

7-3

WF1947/WF1948

7.2 Copying Setting between Channels

4. When the above setting is completed,select [OK] at the bottom of thewindow, and then press the ENTER
key. The copy operation is performed.
When you do not want to copy, select[Cancel] at the bottom of the window
and press the ENTER key, or press the
CANCEL key.

Select [OK], and thenpress the ENTER key tomake a copy.

◼ Remarks
Copying all of [Basic Parameters], [Modulation Parameters], [Sweep Parameters], and [Burst
Parameters] is not equivalent to copying [All Parameters].
The following items are copied only when copying [All Parameters]:• Output on/off state• Oscillation mode
• External addition setting• User-defined unit
• Start-up output on/off setting• Waveform parameters setting for all waveforms (for the copy of [Basic Parameters], thewaveform parameters setting is copied only for the currently used waveforms at the copy
source)• Amplitude/DC offset setting or high level/low level setting

7-4

WF1947/WF1948

7.3 Unifying Settings of 2 Channels

7.3

Unifying Settings of 2 Channels◼Procedure and operation
First, set the 2-channel equivalence setting function to on in the Utility screen.
Next, set items to which you want to set the same setting. When you set setting for one channel,
the same settings are set to the same items for another channel. In addition to the frequency, phase,
amplitude, and DC offset, this is applied to the oscillation mode and waveforms. This is also
applied to the output on/off, burst trigger, sweep start/stop operation.
This function is enabled until the 2-channel equivalence setting function is reset to off.
◼ To turn on/off 2-channel equivalence setting function
Turning on/off 2-channel equivalence setting function is performed in the Utility screen.
In the Utility screen, select [Both], and then press the ENTER key to switch an indicator to [On]from [Off].
This turns 2-channel equivalence setting function on.
If you want to reset to [Off], press the ENTER key again.

In the Utility screen,
select [Both] and press
the ENTER key

The [BOTH] indicator over
the CH1/CH2 key is lit

Other than in the Utility screen, you can switch on/off by holding down the CH1/CH2 key for 2 ormore seconds.

7-5

WF1947/WF1948

7.4 Phase Synchronization between Channels

7.4

Phase Synchronization between Channels

Even if you set the frequency and phase to the same values using the 2-channel equivalence setting
function, the phase relationship between the output waveforms from the 2 channels is changed
accordingly. To synchronize the phases, the phase synchronous operation is required.
This synchronous operation is used for 2-channel independent operation (the channel mode setting is
set to [Indep]).
If you want to always keep the same frequency or frequency ratio and need a phase syn chronization
state, use the 2-channel coordination function.☞ P.7-7, P.7-11
For synchronization of multiple units, ☞ P.8-2◼ Performing synchronization
First, set the channel mode to [Indep] andset the frequency setting for bothchannels to the same value.
In the Utility
screen, select[ Sync], andthen press the
ENTER key to
run the phasesynchronization

The synchronous operation is performedin the Utility screen.
Select [Sync] on the Utility screen, andthen press the ENTER key.
This runs the phase synchronization.
At this time, the phase will be
discontinuous temporarily because bothchannels stop the oscillation once.

◼ Phase relationship after synchronous operation
The oscillation phase for each channel is initialized by the synchronous operation. The phasedifference of the output waveform appears as the difference of the phase setting for each channel.
Even if you make a synchronous operation, changing a frequency later loses the synchronization
relationship. If necessary, make a synchronous operation accordingly.

◼ Operational restrictions
There are restrictions shown in the following table to the synchronous operation: The synchronous
operation is used for 2-channel independent operation. Even if the synchronous operation isdisabled, making a synchronous operation causes both channels to stop the oscillation once.
Item
Waveform
Modulated oscillationmode
Sweep oscillation mode
Burst oscillation mode

Restriction
Disabled for noise and DC.
Disabled for FM and FSK.
Disabled for frequency sweep. Disabled for gated single-shot sweep.
Disabled.

7-6

WF1947/WF1948

7.5 Maintaining Both Channels to Same Frequency (2-Channel Coordination, 2-Phase)

7.5

Maintaining Both Channels to Same Frequency (2-Channel
Coordination, 2-Phase)

If the channel mode is [2Phase], you can change the frequency with the frequencies for both channels
kept the same value while the synchronization relationship is kept. In coordination with the change of
frequency of the channel 1, the frequency of the channel 2 is automatically changed. The channel 2
coordinates with the channel 1 also during the frequency modulation or frequency sweep. Thisfunction is disabled for the burst oscillation and gated single-shot sweep.

◼ Selecting 2-channel coordination
In the Utility screen, set [Channel Mode]to [2Phase] ([Indep] is normally set).
This makes the channel mode an
oscillation with 2-phase.

Set [Channel Mode]to [2Phase]

2PHASE indicator
is litFrequencies for both channels will be thesame and the phase synchronization is
automatically run. Even if changing thefrequency, the synchronization
relationship is kept.
This function controls to keep thesynchronization relationship with the same
frequency also during the frequency
modulation or frequency sweep.
For the 2-phase oscillation, the setting
relating to the frequency can be set only
for the channel 1.

◼Changing phase difference between channels
You can set a phase for each channel in the Oscillator setting screen. The phase between channels
appears as the difference for each phase setting.
Normally, set the phase of the phase reference channel (for example, channel 1) to 0 degree andchange only the phase setting of the channel 2. At this time, the phase setting of the channel 2 is aphase of the channel 2 based on the channel 1. As shown in the figure below, if the phase setting of
the channel 2 is positive, the channel 2 precedes the channel 1 and if it is negative, the channel 2lags behind the channel 1.
CH1 waveform
output (Phasesetting = 0°)

CH2 waveform
outputPhasesetting =positivePhase
setting =negative

7-7

WF1947/WF1948

7.5 Maintaining Both Channels to Same Frequency (2-Channel Coordination, 2-Phase)◼ Operational restrictions
There are restrictions shown in the following table to keep the synchronization relationship and thesame frequency:
Item
Waveform
Modulatedoscillation
mode

FM

FSK

Sweep
oscillation
mode

PM
PSK
AM
DC offset
modulation
PWM
Frequency sweep

Phase sweep
Amplitude sweep
DC offset sweep
Duty sweep
Burst oscillation mode

Restriction
Disabled for noise and DC.
Both CHs are FM. Peak deviation is common.
Modulation source is internal only. Internal modulation waveform andinternal modulation frequency are common.
Both CHs are FSK. Hop frequency is common.
Modulation source is internal only. Internal modulation frequency iscommon.
Both CHs are PM. Modulation setting is independent for each CH.
Both CHs are PSK. Modulation setting is independent for each CH.
Both CHs are AM. Modulation setting is independent for each CH.
Both CHs are DC offset modulation. Modulation setting is independent
for each CH.
Both CHs are PWM. Modulation setting is independent for each CH.
Both CHs are frequency sweep.
Sweep function, sweep range, sweep time, and sweep mode arecommon.
Gated single-shot sweep unavailable.
Single-shot sweep trigger source and sweep internal trigger oscillator arecommon. External trigger source is enabled only for CH1 side.
Both CHs are phase sweep. Sweep setting is independent for each CH.
Both CHs are amplitude sweep. Sweep setting is independent for eachCH.
Both CHs are offset sweep. Sweep setting is independent for each CH.
Both CHs are duty sweep. Sweep setting is independent for each CH.
Disabled

Both channels have the same type of modulation or sweep during the modulation or sweep. If anotherchannel does not need the modulation (other than FM and FSK) or sweep (other than the frequency
sweep), set the modulation width or sweep width of the channel to zero (0).

7-8

WF1947/WF1948

7.6 Keeping Frequency Difference Constant (2-Channel Coordination, 2-Tone)

7.6 Keeping Frequency Difference Constant (2-Channel Coordination,
2-Tone)If the channel mode is [2Tone], you can change the frequency with the frequency difference between
both channels kept constant. In coordination with the change of frequency of the channel 1, thefrequency of the channel 2 is automatically changed. The channel 2 coordinates with the channel 1
also during the frequency modulation or frequency sweep. This function is disabled for the burst
oscillation and gated single-shot sweep.
◼ Selecting 2-channel coordination
In the Utility screen, set [Channel Mode]to [2Tone] ([Indep] is normally set).
This makes the channel mode an
oscillation with constant frequency
difference.

Set [Channel Mode]to [2Tone]

2TONE
indicator is lit

The frequency difference between bothchannels is kept constant.
This function controls to keep thefrequency difference constant also during
the frequency modulation or frequency
sweep.
For the oscillation with the constantfrequency difference, you cannot set thefrequency of the channel 2 directly.

◼ To set the frequency difference

In the Oscillator screen, set the frequency
difference in [Freq] of channel 2.
The frequency of channel 2 results fromadding this frequency difference to thefrequency of channel 1.

Set [Freq] of CH2

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WF1947/WF1948

7.6 Keeping Frequency Difference Constant (2-Channel Coordination, 2-Tone)◼ Operational restrictions
There are restrictions shown in the following table to keep the frequency difference:
Item
Restriction
Waveform
Modulatedoscillation
mode

FM

FSK

Sweep
oscillation
mode

PM
PSK
AM
DC offset
modulation
PWM
Frequency sweep

Phase sweep
Amplitude sweep
DC offset sweep
Duty sweep
Burst oscillation mode

Disabled for noise and DC
Both CHs are FM. Peak deviation is common.
Modulation source is internal only. Internal modulation waveform andinternal modulation frequency are common.
Both CHs are FSK. Hop frequency follows the frequency difference.
Modulation source is internal only. Internal modulation frequency iscommon.
Both CHs are PM. Modulation setting is independent for each CH.
Both CHs are PSK. Modulation setting is independent for each CH.
Both CHs are AM. Modulation setting is independent for each CH.
Both CHs are DC offset modulation. Modulation setting is independent
for each CH.
Both CHs are PWM. Modulation setting is independent for each CH.
Both CHs are frequency sweep.
Sweep range follows the frequency difference.
Sweep function, sweep time, and sweep mode are common.
Gated single-shot sweep unavailable.
Single-shot sweep trigger source and sweep internal trigger oscillator arecommon. External trigger source is enabled only for CH1 side.
Both CHs are phase sweep. Sweep setting is independent for each CH.
Both CHs are amplitude sweep. Sweep setting is independent for eachCH.
Both CHs are offset sweep. Sweep setting is independent for each CH.
Both CHs are duty sweep. Sweep setting is independent for each CH.
Disabled

Both channels have the same type of modulation or sweep during the modulation or sweep. If
another channel does not need the modulation (other than FM and FSK) or sweep (other than thefrequency sweep), set the modulation width or sweep width of the channel to zero ( 0).
The frequency difference of the hop frequency in FSK is restricted to the setting resolution of thehop frequency.
If you select the logarithmic sweep as the frequency sweep, the channel 1 performs the logarithmic
sweep, but the channel 2 does not perform the logarithmic sweep because the channel 2 follows
with the constant frequency difference.

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WF1947/WF1948

7.7 Keeping Frequency Ratio Constant (2-Channel Coordination, Ratio)

7.7 Keeping Frequency Ratio Constant (2-Channel Coordination,
Ratio)
If the channel mode is [Ratio], you can change the frequency with the frequency ratio betw een bothchannels kept constant. In coordination with the change of frequency of the channel 1, the frequencyof the channel 2 is automatically changed.
The channel 2 coordinates with the channel 1 also during the frequency modulation or frequency
sweep. This function is disabled for the burst oscillation and gated single-shot sweep.
◼ Selecting 2-channel coordination
In the Utility screen, set [Channel Mode]to [Ratio] ([Indep] is normally set).
This makes the channel mode an
oscillation with constant frequency ratio.
The frequency ratio between bothchannels is kept constant.
This function controls to keep thefrequency ratio constant also during thefrequency modulation or frequency sweep.
For the oscillation with the constantfrequency ratio, you cannot set thefrequency of the channel 2 directly.

Set [Channel Mode]to [Ratio]

RATIO
indicator is lit◼ To set the frequency ratio

In the Oscillator screen, set the frequency
ratio in [Ratio(N)] and [Ratio(M)] of thechannel 2.
Frequency of channel 2: frequency ofchannel 1 will be N : M.
If you change the frequency ratio, thephase will be discontinuous temporarily
because both channels stop theoscillation once.

Set [Ratio(N)] and [Ratio(M)] of CH2

7-11

WF1947/WF1948

7.7 Keeping Frequency Ratio Constant (2-Channel Coordination, Ratio)◼ Operational restrictions
There are restrictions shown in the following table to keep the frequency ratio:
Item
Restriction
Waveform
Modulatedoscillation
mode

FM

FSK

Sweep
oscillation
mode

PM
PSK
AM
DC offset
modulation
PWM
Frequency sweep

Phase sweep
Amplitude sweep
DC offset sweep
Duty sweep
Burst oscillation mode

Disabled for noise and DC
Both CHs are FM. Peak deviation follows the frequency ratio.
Modulation source is internal only. Internal modulation waveform andinternal modulation frequency are common.
Both CHs are FSK. Hop frequency follows the frequency ratio.
Modulation source is internal only. Internal modulation frequency iscommon.
Both CHs are PM. Modulation setting is independent for each CH.
Both CHs are PSK. Modulation setting is independent for each CH.
Both CHs are AM. Modulation setting is independent for each CH.
Both CHs are DC offset modulation. Modulation setting is independent
for each CH.
Both CHs are PWM. Modulation setting is independent for each CH.
Both CHs are frequency sweep.
Sweep range follows the frequency ratio.
Sweep function, sweep time, and sweep mode are common.
Gated single-shot sweep unavailable.
Single-shot sweep trigger source and sweep internal trigger oscillator arecommon. External trigger source is enabled only for CH1 side.
Both CHs are phase sweep. Sweep setting is independent for each CH.
Both CHs are amplitude sweep. Sweep setting is independent for eachCH.
Both CHs are offset sweep. Sweep setting is independent for each CH.
Both CHs are duty sweep. Sweep setting is independent for each CH.
Disabled

Both channels have the same type of modulation or sweep during the modulation or sweep. If anotherchannel does not need the modulation (other than FM and FSK) or sweep (other than the frequency
sweep), set the modulation width or sweep width of the channel to zero (0).
The peak deviation in FM and the frequency ratio of the hop frequency in FSK are restricted toindividual frequency setting resolution.

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WF1947/WF1948

7.8 Obtaining Differential Output (2-Channel Coordination, Differential)

7.8 Obtaining Differential Output (2-Channel Coordination,
Differential)
If the channel mode is [Diff], you can change the setting with the differential output of both channels
being kept. In coordination with the change of setting of the channel 1, the setting of the channel 2 isautomatically changed. Coordination is performed also during various modulations or sweeps. Thisfunction is disabled for the burst oscillation and gated single-shot sweep.
◼ Selecting 2-channel coordination
In the Utility screen, set [Channel Mode]to [Diff] ([Indep] is normally set).
This makes the channel mode an
oscillation with differential output.

Set [Channel Mode]to [Diff]

DIFF indicator
is lit

The frequency, phase, amplitude, and DC
offset settings of both channels are thesame and the reverse phase waveform
appears in the output. Even if changing
the various setting, the differential output
relationship is kept.
This function controls to keep the
differential output relationship also during
various modulations or sweeps.
For the differential output oscillation, thesetting can be set only for the channel 1(behaves as the oscillator for
one-channel).

◼ Operational restrictions
There are restrictions shown in the following table to keep the differential output:

Item

Restriction

Waveform

Disabled for noise and DC

Modulated oscillation mode

Burst oscillation mode

Modulation source is internal only
Gated single-shot sweep unavailable. External trigger source is enabled only forCH1 side.
Disabled

External addition

Disabled

Sweep oscillation modeCheck
For DC offset of output, both channels have the same value andpolarity. Differential output is made for AC, but it is not made for DC.

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WF1947/WF1948

7.8 Obtaining Differential Output (2-Channel Coordination, Differential)
MEMO

7-14

WF1947/WF1948

8.

Synchronizing Multiple Units

8.1

Connection Procedure ............................................................................................. 8-2

8.2

Performing Synchronization .................................................................................. 8-4

8-1

WF1947/WF1948

8.1 Connection Procedure

Synchronizing multiple units of WF1947 or WF1948 can configure up to 12-phase oscillators (for 6
units of WF1948). You can change a phase and amplitude for each phase independently.
Set the same frequency for all units and channels.

8.1

Connection Procedure

WF1947 or WF1948 as the synchronous reference is called a "master unit." Other WF1947 or
WF1948 is called a "slave unit."◼ Used connectors
External 10 MHz frequency reference input (10MHz REF IN) and frequency reference output(REF OUT) on the rear panel are used.
◼ Cables used for connection
Cable type: Characteristic impedance 50  series coaxial cable with BNC connector (RG-58A/U etc.)
Restriction to cable length: 1 m or less between units, total cable length is 3 m or less◼ Connection method
There are two types of connection methods (connection method 1 and connection method 2).
If the number of units is many, using the connection method 1 can reduce the time difference
between slave units. However, in addition to the coaxial cable, T-type divider and 50 terminating
resistor are required.
The connection method 2 is easy to connect because it can make the connection using only coaxial
cable. However, the time difference between slave units is larger than that of the connection method
1. The maximum connection number of units is fewer than that of the connection method 1.
Any of the built-in crystal oscillator or external 10 MHz clock can be used as the frequency
reference for the master unit. If you use the external 10 MHz as the reference, the frequency of theslave unit will also be the same accuracy as the external reference.
･ Connection method 1
Connect the reference output for the master unit to the reference input for the slave unit inparallel using the T-type divider.
Use the 50 terminating resistor for the reference input for the terminal slave unit.
Time difference between slave units varies depending on the connection cable length(approximately 6 ns/m).
The maximum number of 6 units can be connected, including master and slave units.
Master unit

Externalreference
can be used

Slave unit

T-shaped
dividerSlave unit

T-shaped
divider

8-2

Slave unit

50Ω
termination
resistor

WF1947/WF1948

8.1 Connection Procedure･ Connection method 2
Connect the reference output for the master unit or slave unit to the reference input for the next
slave unit.
Time difference between slave units varies depending on the delay within units (approximately
25 ns) and connection cable length (approximately 6 ns/m).
The maximum number of 4 units can be connected, including master and slave units.

Master unit

Slave unit

Slave unit

Externalreference
can be used

8-3

WF1947/WF1948

8.2 Performing Synchronization

8.2

Performing Synchronization◼ Before synchronization
After connection among the master unit and slave units is finished, perform the setting asfollows:
Master units• Select 2-channel independent operation or 2-phase
operation (in the Utility screen,
set the channel mode setting to [Indep] or [2Phase])(WF1948 only).

Set [Channel Mode] to[Indep] or [2Phase](WF1948 only)Set 10MHz Ref Out
to [Enable]•Enable the frequency reference output (in the Utility
screen, set 10MHz Ref Out to [Enable]).
• Set the frequency for each channel to the frequency
used for synchronous operation of multiple units.
• If you use the external for the frequency reference forthe master unit, enable the external frequency
reference (in the Utility screen, set the externalreference to [Enable]).☞ P.9-4

Set [Channel Mode] to[Indep] or [2Phase](WF1948 only)

Set [Ext Reference] to[Enable]Slave units• Select 2-channel independent operation or 2-phase
operation (in the Utility screen, set the channel modesetting to [Indep] or [2Phase]) (WF1948 only).
•Enable the external frequency reference (in the Utility
screen, set the external reference to [Enable]).
• Set the frequency for each channel to the frequency
used for synchronous operation of multiple units(common to all units and channels).
• For the connection method 2, enable the frequency
reference output (in the Utility screen, set 10MHz Ref
Out to [Enable]).

For the connection method 2,
set 10MHz Ref Out to[Enable]Check that all slave units operate based on the external frequency reference. If the [R ef] icon is lit
without flashing on the status display area in the top of the screen, they operate based on theexternal frequency reference.
If they operate based on the externalfrequency reference, the [Ref] icon is
lit without flashing

8-4

WF1947/WF1948

8.2 Performing Synchronization◼ Performing synchronization
Synchronous operation is performed in the master unit.
Synchronous operation is performed in
the Utility screen of the master unit.
Select [ Sync] on the Utility screen, andthen press the ENTER key.
This runs the phase synchronization.
In the Utility screen,
select [ Sync], andthen press the
ENTER key to run
the phase
synchronization

At this time, the phase will be
discontinuous temporarily because allchannels stop the oscillation once.

When the phase synchronization is run, a message is displayed on each unit.

◼ Phase relationship after synchronous operation
The oscillation phase for each channel is initialized by the synchronous operation. The phasedifference of the output waveform appears as the difference of the phase setting for eachchannel.
Even if you make a synchronous operation, changing a frequency later loses the synchronization
relationship. Even if the synchronization relationship is lost, no message is displayed. If
necessary, make a synchronous operation accordingly.
The synchronization relationship is lost when the connection cable between the master unit andslave unit or between slave units is removed. If you change the setting of channel mode or
external frequency reference, the synchronization relationship is lost.

◼ Operational restrictions
There are restrictions shown in the following table to the synchronous operation: Even if thesynchronous operation is disabled, making a synchronous operation causes all channels to stop
the oscillation once.
Item

Restriction

Waveform

Disabled for noise and DC

Modulated oscillation mode

Disabled for FM and FSK

Sweep oscillation mode

Disabled for frequency sweep. Disabled for gated single-shot sweep.

burst oscillation mode

Disabled

8-5

WF1947/WF1948

8.2 Performing Synchronization
MEMO

8-6

WF1947/WF1948

9.

Using External Frequency Reference

9.1

Purpose of Using External Frequency Reference .................................................. 9-2

9.2

Connection and Usage Procedure of External Frequency Reference .................... 9-2

9-1

WF1947/WF1948

9.1 Purpose of Using External Frequency Reference

9.1

Purpose of Using External Frequency ReferenceThis product uses a built-in crystal oscillator as the frequency reference, but you can also use theexternal 10 MHz clock as the frequency reference.
Generally, the external frequency reference is used for the following purposes:• Use the higher accuracy of the frequency reference (for example, a rubidium frequency standard)than that of the frequency reference built in this product to improve the accuracy and stability of
the frequency.
• Use the common frequency reference with other units to share the common frequency accuracy.
• Synchronize with other WF1947 or WF1948. For this synchronous operation of multiple units,☞ P.8-2

9.2

Connection and Usage Procedure of External Frequency
Reference◼ To connect 10MHz signal
Connect the external 10 MHz signal to the external 10 MHz frequency reference input (10MHzREF IN) BNC terminal on the rear panel.
WF1947

WF1948

10MHz

10MHz

Input characteristics are as follows:
Input voltage

0.5Vp-p ~ 5Vp-p

Maximum allowable input

10Vp-p

Input impedance

1kΩ, AC coupled

Input frequency

10MHz (± 0.5%(± 50kHz))

Input waveform

Sine or square wave (50 ±5% duty)
Insulated from the enclosure and each channel waveform output(maximum 42 Vpk)

Signal GND

If reflection is problem, use the terminating resistor since the input impedance is not 50 .
The signal ground of the external 10 MHz frequency reference input is insulated from theenclosure. Therefore, noise caused by ground-loop does not affect the connection with afrequency standard.
Nor does noise caused by ground-loop affect the connection even when synchronously
connecting multiple units of WF1947 and WF1948.

9-2

WF1947/WF1948

9.2 Connection and Usage Procedure of External Frequency Reference
Note that, in all cases, the floating voltage should be limited to 42 Vpk (DC + AC peak) or
lower to prevent electric shocks.
For the caution for the floating ground connection, ☞"3.3 Cautions on Floating Ground
Connection".

WARNINGTo prevent electric shocks, do not apply a voltage exceeding 42 Vpk (DC + AC peak) between
the ground of the BNC connectors insulated from the enclosure and the enclosure.
Also, do not apply a voltage exceeding 42 Vpk (DC + AC peak) between the grounds of the BNC
connector groups insulated from the enclosure. "BNC connector groups" used here, indicatesmultiple BNC connectors that are connected to a common ground.
If such a high voltage is applied, the internal voltage limiting elements will try to reduce thevoltage, but a too high voltage may cause the product to be burned.

CAUTION
If a difference in potential exists between the ground of a BNC connector insulated from the enclosureand the enclosure, do not short-circuit the hot side of that BNC connector and the enclosure. This may
damage the product.

CAUTION
If a difference in potential exists between the grounds of BNC connectors, do not short circuit these
BNC connector grounds. This may damage the product.

9-3

WF1947/WF1948

9.2 Connection and Usage Procedure of External Frequency Reference◼ Enabling external frequency reference
You can switch the enabled/disabled for the external frequency reference in the Utility screen.
In the Utility screen, select [Ext Reference], and then press the ENTER key to switch an indicatorto [Enable] from [Disable]. This enables the external frequency reference.
If you want to go back to [Disable], press the ENTER key again.
In the Utility screen, select[Ext Referece] and press the
ENTER key

If the available frequency reference isentered, [Valid] is displayed in the[10MHz Ref In] field. Otherwise, [Invalid]
is displayed.

If the setting of [Ext Reference] is [Enable] and the status of [10MHz Ref In] is [Valid], then thisproduct operates using the signal input to the external 10 MHz frequency reference terminal as thefrequency reference.
If the external frequency reference signal breaks on the way, the frequency reference is automaticallyswitched to the built-in frequency reference. After that, if the external frequency reference signal
returns, this product operates using it again as the frequency reference.
What is used as the frequency reference is always displayed on the status display area in the top of
the screen.
If the current frequency reference is external, the [Ref]icon is displayed
If the status of reference input is [Invalid], the icon
flashes

9-4

WF1947/WF1948

10. Using User-defined Units

10.1

About User-defined Unit ...................................................................................... 10-2

10.2

Display and Setting in User-defined Unit ........................................................... 10-2

10.3

Defining User-defined Units ................................................................................ 10-3

10-1

WF1947/WF1948

10.1 About User-defined Unit

10.1 About User-defined Unit
For example, you can set the frequency in units of rpm (number of rotations per minute) instead of
Hz. You can set a value converted to the mechanical deviation quantity or a value converted to the
output voltage after the power amplifier output instead of voltage.
Defining these mutual conversion formulas enables you to use them like the usual units. In thisproduct, these units are called "user-defined unit."
The user-defined unit can be used for the following six parameters:
Frequency, period, amplitude, DC offset, phase, and duty

10.2 Display and Setting in User-defined Unit

Select theuser-defined unit

10-2

When an input field for each parameter
opens, you can change the unit by putting
the cursor on the unit at the right end andusing the up/down arrow key or the modify
knob. The unit name displayed here canbe setting arbitrarily. Only the display unit
is changed without changing the actual
output value, when the unit is changed.

WF1947/WF1948

10.3 Defining User-defined Units

10.3 Defining User-defined Units◼ Setting screen
The setting is done on the Utility screen.

1.

In the Utility screen, select the [UserUnit] field and press the ENTER key.

In the Utility screen, selectthe [User Unit] field and press
the ENTER key

2.

The user-defined unit setting window opens. Select each item, and then press the
ENTER key to set the user-defined unit. Alternatively, you can open the input field bypressing the corresponding soft-key.
The user-defined unit setting
window opens

Setting target
Unit name
FormulaMultiplier of formula
Offset of formula

The following items can be set in this window:
Setting target [Type]
Select one from among frequency, period, amplitude, DC offset, phase, and duty.
Unit name [Unit]
Sets the unit name with up to 4 characters. Enter a character one by one at the cursor position
using the up/down arrow key, the modify knob, or the numeric keypad.
Formula [Form]
Select either one of [(h+n)*m] or [(log(h)+n)*m] as the unit conversion formula. Where, h is an
original value of the setting target. The value converted by this formula is displayed on thescreen when the user-defined unit is actually used.
The unit of h is defined as shown in the following table depending on the setting target:
Setting target
Frequency
PeriodAmplitude

DC offset
Phase
Duty

Unit of hHzsec
If amplitude range is ± FS, then Vp-p
If amplitude range is 0/+FS, -FS/0, then Vpk
A value under the designated load impedance condition in each caseV
A value under the designated load impedance condition
deg
%

10-3

WF1947/WF1948

10.3 Defining User-defined Unitslog is a common logarithm whose base is 10. You need to pay attention to when you use a log
formula for a value with the possibility of negative value such as the DC offset and phase. If avalue before changing to the user-defined unit is zero (0), "-Inf" is displayed when changing to theuser-defined unit using the log. Similarly, if a value before changing to the user -defined unit isnegative, "Over" is displayed when changing to the user-defined unit using the log.
Multiplier and offset of formula [m], [n]Select the multiplier [m] and offset [n] in the selected formula.
After setting each parameter, select [OK] at the bottom of the window and press the ENTER key.

Check
When you use the user-defined unit, the setting resolution may be roughdepending on the setting of multiplier or offset.

◼ To set the frequency in rpm
For example, to display and set the frequency in 1 Hz as the frequency in 60 rpm, set thefollowings and select [OK]:
Type: Freq
Unit: rpm
Form: (h+n)*m
m: 60
n: 0

Next, in the Oscillator screen, open the input field for the frequency, and then change the unit fromHz to rpm.

Unit is changed from Hz
to rpmThis can display and set a value in units of rpm.

10-4

WF1947/WF1948

11. Other Utility Settings

11.1

Selecting Remote Interface [Remote] ................................................................... 11-2

11.2

Display Setting [Display] ..................................................................................... 11-2

11.3

Modify Knob and Modify Direction Setting [Modify Direction] .......................... 11-2

11.4

Operation Sound Setting [Sound] ........................................................................ 11-3

11.5

Self Diagnosis [Self Check] ................................................................................... 11-3

11.6

Product Information Display [Information] ......................................................... 11-3

11-1

WF1947/WF1948

11.1 Selecting Remote Interface [Remote]11.1 Selecting Remote Interface [Remote]
Select the external control interface fromUSB or GPIB.
When you select USB, USB ID isdisplayed.
When you select GPIB, set GPIB address
within the range of 0 to 30, and select EOIfrom Enable or Disable.
For more information about EOI, refer☞Instruction manual (External Control)

GPIB address

GPIB EOI

11.2 Display Setting [Display]
Set the backlight on/off and the brightness
when the backlight is on.

Backlight on/off
and brightness

You can switch whether bright color
characters are displayed on a dark
background or dark color characters are
displayed on a bright background as acolor tone.

Color tone

If the backlight is hidden due to thebacklight off, hold down the [MENU] key
for a while to forcibly turn on the backlight.

11.3 Modify Knob and Modify Direction Setting [Modify Direction]
Select whether the item selection moves
up or moves down when you turn themodify knob clockwise (CW) while theoscillation mode or the waveform
selection list is displayed.

Clockwise item
move direction

11-2

WF1947/WF1948

11.4 Operation Sound Setting [Sound]11.4 Operation Sound Setting [Sound]Set whether or not the beep sounds when
performing key operations, modify knob
operation, or an error occurs.

Operation
sound

11.5 Self Diagnosis [Self Check]
Checks the internal status. Before check,remove all cables other than the power
cable from this product.
If there is any problem, contact us or our
agents.

11.6 Product Information Display [Information]
The model name, firmware version, etc. of
this product are displayed.
There is no items to be set.

Model nameFirmware version

Internal parts version
Last calibration or
adjustment date

11-3

WF1947/WF1948

11.6 Product Information Display [Information]
MEMO

11-4

WF1947/WF1948

12. Troubleshooting

12.1

Error Messages at Power-on ................................................................................ 12-2

12.2

Error Messages during Operation ........................................................................ 12-3

12.3

Conflict Messages for Modulation ........................................................................ 12-7

12.4

Conflict Message for Sweep .................................................................................. 12-8

12.5

Conflict Message for Burst ................................................................................... 12-9

12.6

Suspected Failure ............................................................................................... 12-10

12-1

WF1947/WF1948

12.1 Error Messages at Power-on

12.1 Error Messages at Power-on
At power-on, self-diagnosis is performed and an error message is displayed if there are any problems. If
you encounter any failure, contact us or our representatives. When a message that tells you machine isshut down due to overheat, check installation environment if the environment is not in hot so that the
product become over heat.
Hardware initialization failed
This is an internal error. This is a failure of this equipment.
OSC-Block error
This is an internal error. This is a failure of this equipment.
RAM error
This is an internal memory error. This is a failure of this equipment.
ROM error
This is an internal memory error. This is a failure of this equipment.
Last shutdown caused by overheat
The last power-off was caused by internal overheat.
Check the operating environment and status of this equipment.
Output not turned on due to overload
The output did not become on, because overload of the synchronization/sub -output was detectedeven though the output settings was on.
The output terminal may connect to an outer voltage supply. Check the connection. Exit the overloadstates before make the output turn on.
Output overload detected; Output turned off
The output became off because overload of the waveform output or synchronization/sub-output isdetected even though the output became on based on the output setting at once.

The output terminal may connect to an outer voltage supply. Check the connection. Exit theoverload states before make the output turn on.

12-2

WF1947/WF1948

12.2 Error Messages during Operation

12.2 Error Messages during Operation
Often run-time error messages are displayed when the setting exceeds the allowable output range. For
example, when a rectangular wave is output and you try to set the frequency to 30MHz, an error isdisplayed and the frequency is set to the maximum frequency of a rectangular wave.
Error messages are also displayed for internal overheat and output overload.
This section describes errors displayed on the dialogue window in order of the error number.
12005: Internal overheat detected
The inside of the equipment is overheated.
The ambient temperature may be too high or the equipment may be faulty. It is recommended to turnthe equipment off.
14006: Internal temperature too high; Auto-shutdown will occur
Internal overheat reaches the limit. The equipment is automatically turned off.
The ambient temperature may be too high or the equipment may be faulty.
22017: Function changed to Sine by changing Channel Mode
Any of 2 channels coordination modes was selected when the waveform is noise or DC. The
waveform of this channel is changed to sine wave.
22018: Mode changed to Continuous by changing Channel Mode
Any of 2 channels coordination modes was selected in the BURST mode. It is changed to the CONTmode.
The BURST mode cannot be used in 2 channels coordination modes.
22019: Modulation Source changed to Internal due to Channel Mode
The modulation source is changed to internal due to any of 2 channels coordination modes.
Any of 2 channels coordination modes is selected, the modulation source is set to the internal
regardless of the modulation type.
When the channel mode is 2 phases, constant frequency difference, or constant frequency ratio, themodulation source for FM and FSK is limited to internal. The other types of source are not affectedby this restriction. Try to set up again. When the channel mode is DIFF, source is limited to internal
regardless of the modulation type.
22020: External addition turned off by changing Channel Mode
DIFF mode was selected as the channel mode. Ext Add is turned to off.
External addition cannot be used in the DIFF mode.
22021: SwpMode changed to Single by changing Channel Mode2 phases, constant frequency difference, constant frequency ratio, or differential was selected when
SwpMode was single-shot Gated, it is changed to Single sweep.
In any of 2 channels coordination modes, Gated sweep cannot be used.
22022: Mode changed to Continuous by changing Function
Waveform that does not match the current oscillation condition was selected in the MOD U, SWEEP,or BURST mode, the mode is changed to the Continuous.

For example, when the waveform is changed from pulse wave to sine wave during PWM, themode is changed to continuous because PWM is not available for sine.

12-3

WF1947/WF1948

12.2 Error Messages during Operation

22024: Start-locked occurred due to setting conflict
The operation setting is not adequate in the MODU, SWEEP, or BURST mode. A given oscillation
cannot be started.
When pressing the soft-key [?] on the left end, the message concerning an improper item appears.
22025: SyncOut selection changed to Sync by selection of external modulation
Modulation is changed from internal to external. synchronization/sub-output is set as reference phasesynchronization (Sync).
Modulation synchronization (ModSync) and modulation waveform (ModFctn) can be sele cted assynchronization/sub-output for internal modulation.
22028: Edge time changed due to Width
A given pulse width time cannot be achieved with the current edge time (LE, TE). The edge time
becomes shorter.
The pulse width time takes precedence over the edge time.
22029: Edge time changed due to Duty
A given pulse width duty cannot be achieved with the current edge time (LE, TE). The edge time
becomes shorter.
The pulse width duty takes precedence over the edge time.
22030: Edge time and/or Width changed due to Frequency
The specified frequency cannot be achieved with the current edge time (LE, TE) and pulse width
time. The edge time and the pulse width time are changed.
The Frequency takes precedence over the pulse width time and the edge time.
22031: Edge time and/or Duty changed due to Frequency
The specified frequency cannot be achieved with the current edge time (LE, TE) and pulse width
duty. The edge time and the pulse width duty are changed.
The Frequency takes precedence over the pulse width duty and the edge time.
22032: Selected ARB is missing; Edit Memory ARB assigned
The specified arbitrary waveform does not exist. An arbitrary waveform in the edit memory is
assigned instead of it.
This error happens when an arbitrary waveform used before has been deleted during not used. An
arbitrary waveform is identifies only with the number.
22033: Too narrow or too wide Duty specified; Amplitude may decrease or pulse may be lost
The duty setting is too narrow or too wide. Amplitude may decrease or pulse may be lost.
This event happens when a square whose variable range is extended has the pulse width less thanapproximately 8.4 ns on the low or high side.
22034: Frequency reduced due to Function
The frequency is changed to the lower value based on the waveform.
The upper limit of waveform depends on the waveform.
22035: Duty changed due to Extend-Off
The duty variable range of a square is changed to standard. The duty is changed to the value
restricted by the frequency.
When the duty variable range is standard, it is changes based on the frequency.
22036: Duty changed due to Frequency

12-4

WF1947/WF1948

12.2 Error Messages during Operation
The duty variable range of a square is standard. The duty is changed to the value restricted by thefrequency.
When the duty variable range is standard, it is changes based on the frequency.
22037: High level changed due to Low level
The change to the low level also changes the high level based on the possible output range.
22038: Low level changed due to High level
The change to the high level also changes the low level based on the possible output range.
22039: Not acceptable due to another CH limitation
The specified setting cannot be set due to another channel restriction in 2 -channel equivalencesetting.
22040: Frequency and/or DeltaFreq changed due to Function
The frequency and the frequency difference are changed based on the upper frequency of waveformwhen the channel mode is 2TONE.
22041: Frequency of CH1 changed due to DeltaFreq
The frequency of CH1 is changed to maintain the frequency difference when the channel mode is
2TONE.
The frequency difference takes precedence over the frequency of CH1.
22042: Frequency changed due to Function
The frequency is changed based on the upper frequency of waveform when the channel mode is
RATIO.
22043: Frequency of CH1 changed due to Ratio
The frequency of CH1 is changed to maintain the frequency ratio when the channel mode is RATIO.
The frequency ratio takes precedence over the frequency of CH1.
22044: Output not turned on due to overload
Overload is detected in synchronization/sub-output. The output did not become on.
The output terminal may connect to an outer voltage supply. Check the connection. Exit the overloadstates before make the output turn on.
22149: Modulation Source of CH2 changed to Internal by changing CH1 or CH2 setting
The modulation source of CH2 was set to CH1 external for FSK or PSK. The source is changed toInternal due to the setting change of CH1 or CH2.
The CH2 modulation source can be set to CH1 external only if CH1 and CH2 are same types andexternal is selected as the modulation source of CH1.
22150: Trigger of CH2 changed to Internal by changing CH1 or CH2 setting
The trigger source of CH2 was set to CH1 external for sweep or burst. The trigger source is changed
to Internal due to the setting change of CH1 or CH2.
The trigger source of CH2 can be set to CH1 external only when external is selected as the trigger
source of CH1 in the following conditions.
• CH1 and CH2 have the same sweep type. CH1 and CH2 are in the same sweep mode (except forCont).
• CH1 and CH2 are in the same burst mode (except for auto burst).

12-5

WF1947/WF1948

12.2 Error Messages during Operation

23045: Data out of range; Data discarded
You tried to enter a value outside of setting range. The value entered is discarded.
23129: MOD/ADD IN connector used by external addition now
The MOD/ADD IN connector is used for external addition. Cannot use if with external modulation ata time.
23130: MOD/ADD IN connector used by external modulation now
The MOD/ADD IN connector is used for external modulation. Cannot use if with external addition ata time.
23133: Output overload detected; Output turned off
Overload is detected in waveform output or synchronization/sub-output. The output turned to off.
The output terminal may connect to an outer voltage supply. Check the connection. Exit the overloadstates before make the output turn on.
23134: Self Check failed; Auto-shutdown will occur
The result of the self check failed. Turn the power off.
The equipment may have a failure.
32004: Not able to delete this ARB; This ARB is in current use
An arbitrary wave that is currently output or used cannot be deleted.
In the MODU mode, an arbitrary waveform that is used as an internal modulation wave cannot bedeleted.
35005: File-system error
This is an internal error. This is a failure of this equipment.
60002: ARB waveform under editing not stored; Shutdown?
The arbitrary waveform being edited has not been stored yet.
It will be cleared when the power turns off. Store it as needed.
61056: Data beyond lower limit; Value clipped to lower limit
You are trying to set the value beyond under limit. The value is set to the lower limit.
61057: Data beyond upper limit; Value clipped to upper limit
You are trying to set the value beyond upper limit. The value is set to the upper limit.
61058: Zero data not allowed
Zero cannot be set in this parameter.
61059: Invalid operation
This operation is invalid. You are trying to insert a control point into the impossible place while
editing arbitrary wave.
61060: Invalid operation
This operation is invalid. You are trying to delete a control point that cannot be deleted while editing
an arbitrary wave.

12-6

WF1947/WF1948

12.3 Conflict Messages for Modulation

12.3 Conflict Messages for Modulation
This is a message by pressing soft-key (?), when the specified modulation cannot be performed due toinadequate settings. This message explains improper settings.
HopFreq beyond upper limit for current Function
The hop frequency is beyond the allowable range of the current waveform to output in FSK.
Lower the hop frequency.
MOD/ADD IN connector used by external addition now
The MOD/ADD IN connector is currently used for external addition. It cannot be used for external
modulation.
Turn the external addition function off.
Modulated peak or bottom value out of range[The carrier value + the deviation] or [the carrier value - the deviation] is beyond the allowable range
to output in FM, PM, OFSM, PWM.
Change the carrier value or make the deviation low.
Modulated peak or bottom phase out of range[The carrier value + the deviation] is beyond the allowable range to output in PSK.
Change the carrier value or make the deviation low.
Modulation Type not compatible with current Function
The modulation type is not adequate for the current waveform. For example, PWM is specified forthe sine wave.
Change the modulation type.

12-7

WF1947/WF1948

12.4 Conflict Message for Sweep

12.4 Conflict Message for Sweep
This is a message by pressing soft-key (?), when the specified sweep cannot be performed due toinadequate settings. This message explains improper settings.
Frequency beyond upper limit for Gated sweep
The frequency is beyond the upper frequency of gated sweep.
Lower the frequency.
Gated sweep not available for DC
Gated sweep is no available for DC waveform.
Change the sweep mode to continuous or single-shot.
Start value out of range
The start value is beyond the allowable range to output.
Change the value so that it falls within the range.
Stop value out of range
The stop value is beyond the allowable range to output.
Change the value so that it falls within the range.
Sweep Type not compatible with current Function
The sweep type is not adequate for the current waveform. For example, duty sweep is specified forthe sine wave.
Change the sweep type.

12-8

WF1947/WF1948

12.5 Conflict Message for Burst

12.5 Conflict Message for Burst
This is a message by pressing soft-key (?), when the specified burst cannot be performed due toinadequate settings. This message explains improper settings.
BrstMode not compatible with current Function
The burst oscillation mode is not adequate for the current waveform. For example, trigger burst is
specified for noise.
Change the burst oscillation mode.
Frequency beyond upper limit for current Function
The frequency is beyond the upper frequency of the current waveform.
Lower the frequency.

12-9

WF1947/WF1948

12.6 Suspected Failure

12.6 Suspected Failure
When an anomaly is suspected, perform one of the actions listed below. If this fails to correct the problem,
contact NF Corporation or the distributor.

Contents
Power supply is
not turned on.

The panel
operation is notavailable
Output level isAbnormalSettings with theremote control
are not available.

Does not become
same asdescribed in
Instruction
manualActionReference pageThe power supply out of rated
range is used.

Possible Cause

Use the power supply within the
rated range.

The operation is not normal due toexternal noise, etc.

Install the equipment in quiet
environment far from noise
sources.
Change to the Local stateContact NF Corporation to ask
repairUse in the environment within
the specified range.

2.3 Grounding andpower supply
connection"2.2 Installation"

In the Remote state
Keys and/or modify knobs are
deteriorated
The ambient temperature/humidity
range is out of the performance
guaranteed range.
Warming up is not enough

DC offset is added

Perform warming up for morethan 30 minutes after the powerturns onMake the DC offset to 0V

A user-defined unit is used

Select a standard unit

The load impedance function is
used

Change the setting to Hi-Z

The interface setting is
not adequate.
The GPIB address and the USB ID
are different from the program.
The GPIB address and the USB ID
is same as other equipment.

Use the setting that matches theinterface to use.
Make the GPIB address and theUSB ID match the program.
Set the GPIB address and theUSB ID again so that it does notcoincide with that of equipment.
Description presumes settings
were initialized.
Perform initialization.
Check whether the channel is
CH1 or CH2.

Initialization has not been done.

The channel to operate is opposite.

12-10

—
—
"2.2 Installation"—"4.4.8 To Set DC
Offset""4.4.7 To Set
Amplitude""4.4.12 To Set Load
Impedance"
P.11-2
P.11-2
P.11-2"4.3.8 To Restore
Initial Settings""4.3.6 CH1/CH2 Switching Key
and Active Channel(WF1948 Only)"

WF1947/WF1948

13. Maintenance

13.1

Overview ............................................................................................................... 13-2

13.2

Operation Inspection ............................................................................................ 13-4

13.3

Performance Test .................................................................................................. 13-5

13.3.1Frequency Accuracy Test ........................................................................... 13-5

13.3.2Sine Wave Amplitude Accuracy Test ........................................................ 13-6

13.3.3

DC Offset Accuracy Test ............................................................................ 13-6

13.3.4Sine Wave Amplitude/Frequency Characteristics Test ............................ 13-7

13.3.5Sine Wave Total Harmonic Distortion Test .............................................. 13-8

13.3.6Sine Wave Harmonic Spurious Test ......................................................... 13-8

13.3.7Sine Wave Non-harmonic Spurious Test .................................................. 13-9

13.3.8Square Wave Duty Accuracy Test ............................................................. 13-9

13.3.9Square Wave Leading/Trailingg Time Test ............................................ 13-10

13.3.10

Time Difference Between Channels for 2-Phase (WF1948 Only) ........... 13-10

13-1

WF1947/WF1948

13.1 Overview

13.1 Overview◼What TO DO
To use the equipment under the best condition, following maintenance tasks are needed.
⚫Operation Inspection

Check to see if the equipment is operating correctly.

⚫Performance Test

Check to see if the equipment satisfies the ratings.

⚫Adjustment and calibration

If any rating is not satisfied, we will perform adjustment orcalibration to recover the performance.

⚫Troubleshooting

Should no improvement result, we will investigate into the cause
and failed portion to repair it.

This Instruction Manual describes the operation inspection and the performance testing method thatcan be easily performed.

For advanced inspections, adjustments, calibrations, and troubleshooting, contact us or our
representative.

WARNING
High voltages appear inside of the equipment. Never remove the cover.
No one except the trained service technicians who are thoroughly experienced in the hazard
prevention is allowed to check or touch the inside of this equipment. Do not touch the inside by
yourself in any case.

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WF1947/WF1948

13.1 Overview◼Equipment Used
To perform the operation inspection and performance test, following equipments.

Requirement
DigitalMulti-meter

Power meterand Power
sensorUniversal
Counter
Oscilloscope
Audio analyzer
Spectrum
Analyzer
BNC cable
BNC(f)banana
adapter
BNC(f)-N(m)adapter
BNC(f)-N(f)adapter

AC Voltage
TrueRMS
Accuracy: ± 0.1%
(1kHz ~ 100kHz)
DC voltage
Accuracy: ± 0.1%
100kHz ~ 30MHz
5µW ~ 250mW(-23dBm ~ +24dBm)
Accuracy: 0.02dB
Resolution: 0.01dB
Accuracy: 0.1ppm

More than 300MHz
2GS/s, 50Ω input
Measurement of less than
0.01%, THD
10kHz ~ 1GHz
Resolution: 100Hz
Characteristics impedance: 50Ω
Length: 1m—

ExampleAgilent 3458A

Measurement of AC/DC
voltage less than 100kHz

R&S NRVS, NRV-Z5

Measurement of AC
voltage more than 100kHz

Agilent 53131A
Opt 010 (High Stability
Oven TB)
Agilent DSO6032A

Measurement of
frequency, duty, timeinterval between channels
Measurement of Leading
and Trailing time
Harmonic distortion
measurement
Measurement of
non-harmonic spurious—

levear VP-7722A
Agilent E4411B
Opt 1DR (narrow RBW)—

Characteristics impedance: 50Ω
Characteristics impedance: 50Ω

Intended Purpose

—

13-3

To Connect a BNC cable
to a spectrum analyzer
To Connect a BNC cable
to a power sensor

WF1947/WF1948

13.2 Operation Inspection

13.2

Operation Inspection◼Check Before Operation inspection
Check followings before the operation inspection.
⚫The power supply voltage is within the rated range.
⚫Ambient temperature is within the range of 0 to +40°C.
⚫Ambient relative temperature is within the range of 5 to 85%RH (further more, theabsolute temperature is 1 to 25g/m3).
⚫non-condensing.
◼Function check⚫Check at power-on
Make sure that no error message appears at power-on.
When an error message appears ☞ P. 12-2
When the display shows any problems at the power-on, turn the power off, wait for at least 5
seconds and turn the power-on again.
⚫Self diagnosis
Perform Self Check on the Utility screen.
☞ P. 11-3⚫Check of major functions
To avoid mis-setting, perform initialization (Perform Reset on the Utility screen).
Then, connect the FCTN OUT to the oscilloscope using characteristic impedance 50Ω series coaxial
cable.
Change following settings some times and check they work properly. For items that set numericvalues like the frequency, check become more reliable by operating both a numeric keypad andmodify knobs.
• Waveform (shortcut key: FCTN key FCTN )• Frequency (shortcut key: FREQ key FREQ )• Amplitude (shortcut key: AMPTD key AMPTD )• DC offset (shortcut key: OFFSET key OFFSET )• Output on/off ( CH 1, CH 2, or OUTPUT )⚫Check of GPIB and USB
Perform some of setting changes performed in the check of important function section on the
GPIB and USB. Verify that Changes of the output is the same.
In this case, GPIB or USB is displayed on the status display area on the top of the screen.
Check also that pressing soft-key Local while GPIB or USB is displayed on the status clears thestatus display and returns to the local status (except for during local lockout condition).

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WF1947/WF1948

13.3 Performance Test

13.3

Performance Test

◼Performance Test
The performance test is performed as a part of preventive maintenance to prevent the productperformance from being deteriorated.
Perform the performance test when an acceptance inspection, a periodic inspection, or a performancecheck after repaired of this product is needed.
After the performance test, when the product does not meet the specification, it needs to be repaired.
Please contact the NF or representatives.
◼Check before the performance test
Check followings before the performance test.
⚫The power supply voltage is within the rated range.
⚫Ambient temperature is within the range of +20 to +30°C.
⚫Ambient respective temperature is within 20 to 70%RH .
⚫non-condensing.
⚫warming up for more than 30 minutes is performed.
◼Preparations before performance test
⚫Use a coaxial cable whose characteristic impedance is 50, width is RG-58A/U or more,
and length is 1m or less and that has BNC connectors on both ends as a signal cable.
⚫For items that 50 termination is specified, set the input impedance for connecting
equipments to 50.
⚫For equipments that cannot set to 50 input, install 50 terminator (feed-throughterminator) at input of the equipments.
⚫Measure up to 24dBm signals (when amplitude setting 20Vp-p /open). Use a coaxial
attenuator separately as needed not to exceed the allowable input of the equipment.
Note that the power meter (power sensor) and the spectrum analyzer are speciallydamaged easily.
⚫Items described here is that they still need to be changed after performing initial setting(perform Reset on the Utility screen) and turn output on.

13.3.1 Frequency Accuracy Test
Connection: FCTN OUT → Universal counter input (50 termination)
Use a coaxial cable.
Setting: Set Frequency to 1MHz and Amplitude to 10Vp-p/open after initial setting.
Measurement: Set universal counter to the frequency measurement mode and measure thefrequency.
Judgment: It is normal when the value falls within the following.
However, the equipment may vary across the ages up to ± 1ppm per a year. If one year
has passed since the equipment was shipped, it may be deteriorated within ± 4ppm
(999.996kHz  1.000004MHz).
Rating range
0.999997MHz ~ 1.000003MHz

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13.3 Performance Test

13.3.2 Sine Wave Amplitude Accuracy Test
: FCTN OUT → Digital multi-meter (AC voltage TrueRMS measurement)

Connection

Use a coaxial cable.
Setting: The following table (Frequency is set to 1kHz) shows the amplitude after
initial setting.

Measurement: Measure the output voltage for each waveform as the effective value.

Judgment: It is normal when the value falls within the following table.

Amplitude setting (load open value)

Rating range

20Vp-p (7.071Vrms)

7.014Vrms ~ 7.128Vrms

5Vp-p (1.768Vrms)

1.753Vrms ~ 1.783Vrms

3Vp-p (1.061Vrms)

1.051Vrms ~ 1.070Vrms

1Vp-p (353.6mVrms)

350.0mVrms ~ 357.1Vrms

0.3Vp-p (106.1mVrms)

104.5mVrms ~ 107.6mVrms

0.1Vp-p (35.36mVrms)

34.37mVrms ~ 36.35mVrms

0.02Vp-p (7.071mVrms)

6.307mVrms ~ 7.835mVrms

13.3.3 DC Offset Accuracy Test
◼ DC only
Connection: FCTN OUT → Digital multi-meter (DC voltage measurement)

Setting: Set waveform to DC after initial setting. The following table shows the DC
offset.

Measurement: Measure the output voltage as DC.

Judgment: It is normal when the value falls within the following table.

DC offset setting (load open value)

Rating range± 10V± 9.895V ~± 10.105V± 3V± 2.965V ~± 3.035V± 1V± 0.9850V ~± 1.0150V

0V-5.000mV ~ +5.000mV◼ AC+DC
Connection: FCTN OUT → Digital multi-meter (DC voltage measurement)

Setting: Set oscillation mode to BURST, burst mode to GATE, trigger to external off(the oscillation of the sine wave stops at 0 degree).
The following table shows the amplitude. DC offset setting is leave 0 V.

Measurement: Measure the output voltage as DC.

Judgment: It is normal when the value falls within the following table.

Amplitude setting (load open value)

Rating range

6.4Vp-p-37.00mV ~ +37.00mV

3.5Vp-p-22.50mV ~ +22.50mV

1.3Vp-p-11.50mV ~ +11.50mV

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WF1947/WF1948

13.3 Performance Test

13.3.4 Sine Wave Amplitude/Frequency Characteristics Test
◼ 100kHz or lower: FCTN OUT → Digital multi-meter (AC voltage TrueRMS measurement,

Connection

and 50 termination)
Use a coaxial cable.
Setting: The following table shows the amplitude and frequency after initialization.

Measurement: Measure the output voltage for each frequency as the effective value.

Judgment: For each amplitude setting, it is normal when the measurement error foreach frequency based on the measurement values at 1kHz falls within therange of the following table. (The line at right end of the table is used in thenext section.)

Amplitude
setting(Load open
valued)20Vp-p
5Vp-p
3Vp-p
1Vp-p
0.3Vp-p0.1Vp-p

At 1kHz
Measured value

At 50kHzError

At 100kHz
Error

Error of each amplitude at
100kHz is as follows.

Reference value
Reference value
Reference value
Reference value
Reference value
Reference value± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB± 0.1dB

X1(dB)
X2(dB)
X3(dB)
X4(dB)
X5(dB)
X6(dB)◼ More than 100kHz
Connection: FCTN OUT → Power meter (Power sensor)
Use a coaxial cable. Measure a signal up to approx. 24dBm. Use a coaxial
attenuator separately not to exceed the allowable input of the power sensor.

Setting: The following table shows the amplitude and frequency after initialization.

Measurement: Measure the output voltage or the power at each frequency.

Judgment: For each amplitude setting, it is normal when the measurement error foreach frequency based on the measurement values at 100kHz falls within therange of the following table.
Add the error Xn(n=1-6), previously measured at 100kHz by the digital
multi-meter, to the judgement range.

For example, When X1 is -0.05dB, the judgment range at 20Vp-p and 5MHz is -0.1dB to 0.2dB.
Amplitude
setting(Load open
valued)Measuredvalue at
100kHzError at
300kHzError at
1MHz

5MHz
Error atError at
10MHz

Error at
20MHz

Error at30MHz

20Vp-p
5Vp-p
3Vp-p
1Vp-p
0.3Vp-p0.1Vp-pReference value
Reference value
Reference value
Reference value
Reference value
Reference value-X1±0.15dB-X2±0.15dB-X3±0.15dB-X4±0.15dB-X5±0.15dB-X6±0.15dB-X1±0.15dB-X2±0.15dB-X3±0.15dB-X4±0.15dB-X5±0.15dB-X6±0.15dB-X1±0.15dB-X2±0.15dB-X3±0.15dB-X4±0.15dB-X5±0.15dB-X6±0.15dB-X1±0.3dB-X2 ±0.3dB-X3 ±0.3dB-X4 ±0.3dB-X5 ±0.3dB-X6 ±0.3dB-X1±0.3dB-X2±0.3dB-X3±0.3dB-X4±0.3dB-X5±0.3dB-X6±0.3dB-X1±0.8dB-X2 ±0.5dB-X3 ±0.5dB-X4 ±0.5dB-X5 ±0.5dB-X6 ±0.5dB

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WF1947/WF1948

13.3 Performance Test

13.3.5 Sine Wave Total Harmonic Distortion Test
Connection: FCTN OUT → audio analyzer (50 termination)
Use a coaxial cable. If the audio analyzer does not have a 50 termination,
install a 50 terminator (feed-through terminator) at the input of theequipment.

Setting: Set Frequency to 20kHz after initial setting. The following table shows theamplitude.

Measurement: Measure the total harmonic distortion (THD). (Note that it is not THD + N.)

Judgment: It is normal when the value falls within the following table.

Amplitude setting (load open value)

Total harmony distortion (THD)

20Vp-p

0.04% or lower

3Vp-p

0.04% or lower

1Vp-p

0.04% or lower

13.3.6 Sine Wave Harmonic Spurious Test
Connection: FCTN OUT → Spectrum analyzer
Use a coaxial cable. Measure a signal up to approx. 24dBm. Use a coaxial
attenuator separately not to exceed the allowable input of the spectrum
analyzer.

Setting: The following table shows the amplitude and frequency after initializat ion.

Measurement: Measure the max value of the harmonious spurious 5 until next.
Make an attenuator of spectrum analyzer high until the relative level of thefundamental wave is stable.

Judgment: It is normal when the value falls within the following table.

Amplitude
setting(Load open
valued)The max
harmonious
spurious level up to
5th at frequency
setting 100kHz

The max harmonious
spurious level up to
5th at frequency
setting 1MHz

The max harmonious
spurious level up to
5th at frequency
setting 10MHz

The max
harmonious
spurious level up to
5th at frequency
setting 30MHz

20Vp-p-55dBc or lower-55dBc or lower-43dBc or lower-30dBc or lower

3.5Vp-p-60dBc or lower-60dBc or lower-50dBc or lower-40dBc or lower

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WF1947/WF1948

13.3 Performance Test

13.3.7 Sine Wave Non-harmonic Spurious Test
Connection: FCTN OUT → Spectrum analyzer
Use a coaxial cable. Measure a signal up to approx. 24dBm. Use a coaxial
attenuator separately not to exceed the allowable input of the spectrum
analyzer.

Setting: The following table shows the amplitude and frequency after initializat ion.

Measurement: Measure the max value of the non-harmonious spurious .

Judgment: It is normal when the value falls within the following table.

Amplitude
setting(Load open
valued)Max
non-harmonious
spurious levelat the frequency
100kHzMax
non-harmonious
spurious levelat the frequency
setting 1MHzMax
non-harmonious
spurious levelat the frequency
level 3MHzMax
non-harmonious
spurious levelat the frequency
level 30MHz

20Vp-p-65dBc or lower-65dBc or lower-65dBc or lower-45dBc or lower

3.5Vp-p-65dBc or lower-65dBc or lower-65dBc or lower-45dBc or lower

1Vp-p-65dBc or lower-65dBc or lower-65dBc or lower-45dBc or lower

13.3.8 Square Wave Duty Accuracy Test
Connection: FCTN OUT → Universal counter (50 termination)
Use a coaxial cable.

Setting: Set the waveform to square and the amplitude to 20Vp-p/open after initial
setting. The following table shows the duty variable range setting, thefrequency setting, and the duty setting.

Measurement: Set the universal counter to duty measurement mode. Set trigger level of theuniversal counter to 0V. Average the measured values because they vary due
to jitter (especially the duty variable range is extend).

Judgment: It is normal when the value falls within the following table.

◼Duty variable range standard
Frequency

Duty

100kHz0.9% to 1.1% at 1% setting

49.9% to 50.1% at 50% setting

98.9% to 99.1% at 99% setting

1MHz

4% to 6% at 5% setting

49% to 51% at 50% setting

94% to 96% at 95% setting

3MHz

37% to 43% at 40% setting

47% to 53% at 50% setting

57% to 63% at 60% setting◼Duty variable range extend
Frequency

Duty

100kHz0.9% to 1.1% at 1% setting

49.9% to 50.1% at 50% setting

98.9% to 99.1% at 99% setting

1MHz

4% to 6% at 5% setting

49% to 51% at 50% setting

94% to 96% at 95% setting

3MHz

37% to 43% at 40% setting

47% to 53% at 50% setting

57% to 63% at 60% setting

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13.3 Performance Test

13.3.9 Square Wave Leading/Trailing Time Test
: FCTN OUT → Oscilloscope (50 termination)

Connection

Use a coaxial cable.
Setting: Set the waveform to square, the frequency to 1MHz, and the amplitude to
20Vp-p/open after initial setting.
The following table shows the duty variable range.

13.3.10

Measurement: Observe the waveform and measure the Leading and Trailing time.

Judgment: It is normal when the value falls within the following table.

Duty variable range

Leading time, Trailing timeStandard

17ns or lower

Extend17ns or lower

Time Difference Between Channels for 2-Phase (WF1948 Only)
Connection: CH1 FCTN OUT → Universal counter CH1 (50 termination)
CH2 FCTN OUT → Universal counter CH2 (50 termination)
Use coaxial cables whose length and kind are same.

Setting: Set the channel mode to 2 phases, amplitude to 20Vp-p/open, phase of CH2
to 180deg, and frequency to 10MHz. after initial setting. The following tableshows the waveform.

Measurement: Measure the interval between CH1 and CH2 by setting universal counter tothe time interval mode CH1 to CH2. Set the trigger level of the universal
counter to 0V and the trigger polarity to rising for CH1 and CH2. Measured
values vary. Average them.

Judgment: It is normal when the value falls within the following table.

Waveform

Rating range

Sine wave

30ns ~ 70ns

Square (duty variable range standard)

30ns ~ 70ns

Square (Duty variable range extend)

30ns ~ 70ns

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WF1947/WF1948

14. List of Initial Settings

14-1

WF1947/WF1948

14 List of Initial Settings

When initialization is performed on the Utility screen (Reset), settings are initialized as follows.
These items are also stored in the setting memory (except for output on/off setting).
The arbitration waveform memory, the setting memory, the user-defined unit setting, the output
setting at power-on, the remote setting, and the panel operation settings are not initialized. The
user-defined unit setting is not initialized. However, it stored in the setting memory.

◼Output setting
Oscillation mode

Continuous oscillation

Waveform

Sine wave

Polarity and amplitude range

Normal, ± FS

Frequency

1kHz

Amplitude

0.1Vp-p

DC offset

0V

Range

Auto

Load impedance

Open

Phase

0 degree

Output Off
Synchronization/Sub-output

Reference phase synchronization◼Waveform
Square wave duty

Standard range, 50%

Pulse wave duty

50%

Pulse wave Leading/Trailing time

1µs

Ramp wave symmetry

50%◼Modulation
Modulation typeFM

FM peak deviation

100Hz

FSK hop frequency

1.1kHzPM peak deviation

90°

PSK frequency

90°

AM modulation depth

50%

DC offset modulation peak deviation

0.1V

PWM peak deviation

10%

Modulation source

internal, sine wave, 100Hz

FSK/PSK external modulation input polarity

positive

Synchronization/Sub-output

Internal modulation synchronization

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14 List of Initial Settings◼Sweep
Sweep type

Frequency

Frequency sweep range

1kHz ~ 10kHz

Phase sweep range-90°~ 90°

Amplitude sweep range

0.1Vp-p ~ 0.2Vp-p

DC offset sweep range-0.1V ~ 0.1V

Duty sweep range

40% ~ 60%

Sweep time

0.1secSweep Mode

Continuous

Trigger source

Internal, 1sec

External trigger input polarity

Fall

Sweep function

One way, linear

Each marker value

5kHz, 0°, 0.15Vp-p, 0V, 50%

Stop level

Off, 0%External control input

Disabled

Oscillation stop unit when gated single

1 cycleSynchronization/Sub-output

Sweep synchronization, marker on◼BurstBurst mode

Trigger burst

Mark wave number

1 cycleSpace wave number

1 cycleTrigger source

Internal, 10msec

External trigger input polarity

Fall

Trigger delay

0s

Stop level

Off, 0%Stop oscillation unit at gate

1 cycleSynchronization/Sub-output

Burst synchronization◼ 2-Channel Coordination (WF1948 Only)
Channel mode

Independent

Frequency difference

0Hz

Frequency ratio

1:1

Same value setting

OFF◼Others
Use of user-defined unit

Cancel

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14 List of Initial Settings
External 10 MHz frequency reference

Disabled

External addition

OFF

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14 List of Initial Settings

Followings are shipping settings that are not changed with initialization.

◼Definition of user-defined unit
Unit nameusr1 ~ usr6

Formula(h+n)*m

m

1

n

0

◼Output setting at power-on, panel operation settings
Output at power-on

OFF

Indicator

Back light on, dark color

Modify direction setting

Right and downward

Operation soundON◼Remote setting
Interface

USB

GPIB address

2

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14 List of Initial Settings
MEMO

14-6

WF1947/WF1948

15. Specifications

15.1

Oscillation Mode ................................................................................................... 15-2

15.2

Waveform .............................................................................................................. 15-2

15.3

Frequency, Phase .................................................................................................. 15-3

15.4

Output Characteristics ......................................................................................... 15-3

15.5

Signal Characteristics .......................................................................................... 15-5

15.6

Modulated Oscillation Mode ................................................................................. 15-7

15.7

Sweep Oscillation Mode ...................................................................................... 15-10

15.8

Burst Oscillation Mode ....................................................................................... 15-12

15.9

Triggers ............................................................................................................... 15-14

15.10 Other I/Os ........................................................................................................... 15-14
15.11 2-Channel Coordination (WF1948 Only) ........................................................... 15-16
15.12 Synchronization of Multiple Units ..................................................................... 15-17
15.13 User-defined unit ................................................................................................ 15-18
15.14 Other Functions .................................................................................................. 15-18
15.15 General Characteristics ...................................................................................... 15-19

15-1

WF1947/WF1948

15.1 Oscillation mode

Numeric values marked as *1 are guaranteed values. The other numeric values are notguaranteed values but nominal values or typical values (mark as typ.).
If not specified, the condition is that oscillation is continuous, the load is 50 , the amplitudesetting is 10Vp-p/50, the DC offset setting is 0V, the auto range, the amplitude range of
waveform is ±FS, the extend addition is off, and AC voltage is effective value measurement.

15.1 Oscillation mode
Continuous, modulation, sweep, burst

15.2 Waveform
15.2.1 Standard Waveform
Types

Sine, Square, Pulse, Ramp, Noise (Gaussian distribution),
DC

Polarity

Normal, invert (Switch)
Except for DC

Amplitude range-FS/0, ±FS, 0/+FS (switch)
Except for DC

15.2.2 Arbitrary Waveform
Waveform length

Number of control points 2 to 10,000 or
4K to 512K word (2 n, n=12 to 19)
Remarks: Liner interpolation is performed between
control points.

Total amount of save waveforms

Maximum 128 waves or 4M words (common in CH1 and2)
Saved in non-volatile memories

Resolution of waveform data amplitude 16bit
Sampling rate

120MS/sPolarity

Normal, invert (Switch)

Amplitude range-FS/0, ±FS, 0/+FS (switch)

Output bandwidth

25MHz

-3dB

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15.3 Frequency, phase

15.3

Frequency, phase

Frequency setting range
Oscillation mode
Waveform

Sine wave
Rectangular wave
Pulse wave
Ramp wave
Noise
DC
Arbitrary waveform

Continuous, modulation,
Sweep (gated single)
sweep (continuous and single)
Burst
0.01µHz~30MHz
0.01µHz~10MHz
0.01µHz~20MHz
0.01µHz~10MHz
0.01µHz~20MHz
0.01µHz~10MHz
0.01µHz~5MHz
Fixed to equivalent bandwidth 26MHz
Set the frequency invalid
0.01µHz~5MHz

Frequency setting resolution

0.01µHz

Frequency setting with a period

Setting with frequency that is inverse number of set
periodFrequency accuracy at shipping time
Frequency secular change*1*1

Setting range of the phase± (3ppm + 2pHz of setting)±1ppm/ year
-1800.000° to +1800.000° (resolution 0.001°)
Except for noise and DC
Remarks: A phase setting value at the continuous
oscillation mode is corresponding to the phase of the
waveform output at synchronization output.

15.4

Output Characteristics

15.4.1 Amplitude
Setting range

0Vp-p20Vp-p/open
0Vp-p10Vp-p/50
A peak value combined waveform amplitude and DC
offset is limited to±10V or lower/open.

Setting resolution

999.9mVp-p or lower 4 digits or 0.1mVp-p
More than 1Vp-p

Accuracy*1

5 digits of 1mVp-p±(Amplitude setting[Vp-p] * 0.8%+2mVp-p)/open
Conditions: 1kHz sine wave, amplitude setting 20mVp-p
or higher/open

Approval unit

Vp-p, Vpk, Vrms, dBV, dBm

Range

Auto, hold (switch)
Maximum output voltage range: 20Vp-p, 4Vp-p, 0.8Vp-p
Amplitude attenuator range: 0dB,-10dB,-20dB,-30dB

Resolution of waveform amplitude

16bit
Conditions: Amplitude setting 8mVp-p or more/open
standard waveform
Remarks: When the amplitude is below the setting
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15.4 Output Characteristics
described above or during AM/amplitude sweep,
the amplitude is reduced digitally, the amplituderesolution become lower.

15.4.2 DC Offset
Setting range±10V/open, ±5 V/50
A peak value combined waveform amplitude and DC
offset is limited to ±10V or lower/open.

Setting resolution±499.9mV or lower 4 digits or 0.1mV±0.5V or higher 5 digits or 1mV

Accuracy*1± (|1% of the setting of the DC offset [V]|+5mV+Amplitude setting[Vp-p] * 0.5%)/open
Conditions: Continuous oscillation, 10MHz or lower, sine
wave, load open, auto range, external
addition off, and 20°C to 30°C
Beyond the temperature range of 20°C to 30°C, add
1mV/°C typ.

Range

Auto, hold (switch)
Maximum output voltage range: 20Vp-p, 4Vp-p, 0.8Vp-p
When waveform is DC, it applies to DC offset only.
Otherwise, common in the amplitude range.

15.4.3 Load Impedance Setting
Function
Setting range

Set and display the amplitude and the DC offset of theoutput terminal voltage at a specified load condition.
1 to 10k (resolution 1), 50, High-Z (load open)

15.4.4 Waveform Output
Output On/Off control

On, off (switch)
Output impedance approx. 100k when off

Output impedance

50, Unbalanced

Short protection

Protect against the signal GND short

Output connector

Front panel, BNC receptacle

15.4.5 Synchronization/Sub-output
Output signal

Reference phase synchronization
output waveform

Reference phase synchronization, internal modulationsynchronization, burst synchronization, seep
synchronization, internal modulation signal, sweep X
drive (switch)
Square wave that rises at zero degree of reference phase
for waveform output and duty 50%.
When the waveform is noise or DC, fixed to low level.

15-4

WF1947/WF1948

15.5 Signal Characteristics
Output voltage

Output impedance

TTL level (low level 0.4V or lower, high level 2.7V orhigher/open) (each type of synchronized signal)-3V to +3V/open (internal modulation signal)
0V to +3V/open (sweep X drive)
50Ω, Unbalanced

Load impedance

50  or higher recommended

Output connector

Front panel, BNC receptacle

15.5

Signal Characteristics

15.5.1 Sine Wave
Amplitude frequency characteristics *1
100kHz±0.1dB

100kHz5MHz±0.15dB

5MHz20MHz±0.3dB

20MHz30MHz±0.5dB (amplitude setting 2.8Vp-p or higher/±0.8dB at
50)Conditions: Amplitude 50mVp-p to 10Vp-p/50, andreference frequency 1kHz

Total harmonic distortion (THD) *1
20Hz20kHz

0.04% or lower
Conditions: Amplitude setting 0.25Vp-p to 10Vp-p/50

Harmonic spurious*1

Conditions: Amplitude setting

0.5Vp-p2Vp-p/50

2Vp-p10Vp-p/50

1MHz-60dBc or lower-55dBc or lower

1MHz10MHz-50dBc or lower-43dBc or lower

10MHz30MHz-40dBc or lower-30dBc or lower

Non-harmonic spurious
1MHz-65dBc or lower*1, -70dBc or lower typ.

1MHz3MHz-65dBc or lower*1

3MHz30MHz-65dBc+6dB/oct or lower *1
Conditions: Measured at amplitude setting 0.5Vp-p to
10Vp-p/50, 250MHz bandwidth

15.5.2 Rectangular Wave
Duty
Variable range (switch)

Standard, extended (switch)
Standard range: Duty can be changed within the range
where jitter is low and a pulse does not disappear.
The setting range of the duty narrows as thefrequency rises.
Duty is fixed to 50% at 20MHz

15-5

WF1947/WF1948

15.5 Signal Characteristics
Duty is variable at the range of 10 to 90% at
4MHz
Extended range: There is jitter of 2.5ns rms or lower typ.,and the duty can be always changed at the
maximum range. Averagely, pulses are equal to
the set duty, even though when the pulse width isnarrower than 8.4ns, pulses may disappear.
Setting range

Standard

range

0.0100%to

99.9900%(resolution

0.0001%)
Extended range 0.0000% to 100.0000% (resolution
0.0001%)
Lower and upper limit ofstandard range setting

Upper limit (%) 100 - frequency (Hz)/400,000
Lower limit (%) frequency (Hz)/400,000

Duty accuracy*1
100kHz±0.1% of period (duty setting is 1% to 99%)

100kHz1MHz±1% of period (duty setting is 5% to 95%)

1MHz3MHz±3% of period (duty setting is 40% to 60%)

Leading /Trailing time

17ns or lower*1, 15.5ns or lower typ.
However, for burst oscillation and gated single sweep
with a stop level is set, it is approx. 20ns.
Conditions: 50 load, DC offset setting 0V, andamplitude setting 10Vp-p/50

Overshoot

5% or less typ.

JitterDuty variable range standard 300ps rms or less typ.
(100Hz or higher)
Duty variable range extended 2.5ns rms or less typ.

15.5.3 Pulse Wave
Pulse width
Duty setting range

0.0170% to 99.9830% (resolution 0.0001%)

Time setting range

24.00ns to 99.9830Ms (resolution 0.001% or less of
period or 0.01ns)
Setting range of pulse width duty and pulse width time arelimited by frequency, Leading time and Trailing time.

Upper or lower limit oftime setting

Upper limit (s)period - (Leading time + Trailing time) * 0.8
Lower limit (s)(Leading time + Trailing time) * 0.8
15-6

WF1947/WF1948

15.6 Modulated Oscillation Mode
Upper and lower limit of duty setting are computed byupper and lower value/period above.
Leading time, Trailing time
Setting range

15.0ns to 62.5Ms (resolution 3 digits or 0.1ns)
Independent setting of Leading/Trailing time
Leading time and Trailing time is limited by frequency,
pulse width duty, and pulse width time.

Minimum setting value

Which is lower 0.01% of period or 15ns.

Overshoot

5% or less typ.

Jitter500ps rms of higher typ. (10kHz or more)
2.5ns rms of higher typ. (less than 10kHz )15.5.4 Ramp Wave
Setting range of symmetry

15.6

0.00% to 100.00% (resolution 0.01%)

Modulated Oscillation Mode

15.6.1 General
Modulation type

FM, FSK, PM, PSK, AM, DC offset modulation, PWM

Modulation operation

Start and stop

Modulation source
Except for FSK and PSK

Internal, external (switch)
Source of CH2 cannot be same as CH1

FSK, PSK

CH1: Internal, CH1 external input terminal (switch)
CH2: Internal, CH1 and CH2 external input terminal(switch)(CH1 external input on CH2 is enabled only when
external input is selected on CH1.)
External input of FSK and PSK uses an external trigger
input terminal.

Internal modulation waveform
Except for FSK and PSK

Sine wave, square wave (duty 50%), triangle wave
(symmetry 50%), rising ramp wave, falling ramp wave,
noise, arbitrary wave

FSK, PSK

Square wave (duty 50%)

Internal modulation frequency
Except for FSK, PSK, and DC offset modulation
0.1mHz to 1MHz (resolution 8 digits or 0.1mHz)
FSK, PSK

0.1mHz to 3MHz (resolution 8 digits or 0.1mHz)

DC offset modulation

0.1mHz to 100kHz (resolution 8 digits or 0.1mHz)

Internal modulation synchronization output
Output waveform

A square wave with duty 50% rising at the zero phase of
the internal modulation waveform.
15-7

WF1947/WF1948

15.6 Modulated Oscillation Mode
When internal modulation waveform is noise, the level isfixed to low.
Output connector

Shared with synchronization/sub-out connector

Internal modulation signal output
Output voltage-3V to +3V/open

Output connector

Shared with synchronization/sub-out connector

External modulation input (except for FSK and PSK)
Input voltage range±1V Full scale

Maximum allowable input±2V

Input impedance

10k, Unbalanced

Input frequency

DC40kHz (-3dB)

input connector

Front panel (WF1947)/ rear panel (WF1948), BNC
receptacle
Shared with output addition input. It cannot be used withadditional operation at a time

External modulation input ( FSK and PSK)
Polarity

Positive, negative (switch)

Input frequency

DC3MHz

input connector

External trigger input is used
Input signal and input impedance depend on external
trigger input specification

Signals Selectable for Synchronization/Sub-output
Reference phase synchronization
Internal synchronization (only when modulation source isinternal)
Internal signal (only when modulation source is internal
and not FSK and PSK)

15.6.2 FM
Carrier waveformStandard waveform except for noise, pulse wave, and DC
and an arbitrary waveform.

Peak deviation setting range

0.00µHz to 15MHz or lower (resolution eight digits or
0.01µHz)
Carrier frequency ± peak deviation is limited within theallowable range of frequency for each carrier waveform.

15.6.3 FSK
Carrier waveformStandard waveform except for noise, pulse wave, and DC
and an arbitrary waveform.

Hop frequency setting range

Within the allowable range of frequency for each carrier
waveform (resolution 8 digits or 0.01µHz)

15-8

WF1947/WF1948

15.6 Modulated Oscillation Mode

15.6.4 PM
Carrier waveformStandard waveform except for noise and DC and an
arbitrary waveform.

Peak deviation setting range

0.000° to 180.000° (resolution 0.001°)
Carrier phase ± peak deviation is limited within the rangeof ±1800°.

15.6.5 PSKCarrier waveformStandard waveform except for noise and DC and an
arbitrary waveform.

Deviation setting range-1800.000°to +1800.000°(resolution 0.001°)
Carrier phase + deviation is limited within the range of±1800°.

Remarks

Amplitude frequency characteristic of sine wave during
PSK is limited 25MHz to -3dB.

15.6.6 AMa) Non-DSB-SC
Carrier waveformStandard

waveform

except

for

DC

and

arbitrary

waveform.
Modulation depth setting range

0.0% to 100.0% (resolution 0.1%)

Remarks

When the modulation depth is 0%, amplitude becomesequal to 1/2 of setting.

b) DSB-SC (Double Side Band - Suppressed Carrier)
Carrier waveformStandard

waveform

except

for

DC

and

arbitrary

waveform.
Modulation depth setting range

0.0% to 100.0% (resolution 0.1%)

Remarks

When the modulation depth is 100%, maximum amplitude
becomes equal to setting.
The component of the carrier frequency is zero during
DSB-SC.

15.6.7 DC Offset Modulation
Carrier waveformStandard waveform and arbitrary waveform.

Peak deviation setting range

0V to 10V/open
Carrier DC offset ±peak deviation is limited within theallowable range of DC offset for each carrier waveform

15.6.8 PWM
Carrier waveform

Square wave and pulse wave

Peak deviation setting range
Rectangular wave
Duty variable range standard 0.0000% to 49.9900% (resolution 0.0001%)
Duty variable range extend
Pulse wave

0.0000% to 50.0000% (resolution 0.0001%)
0.0000% to 49.9000% (resolution 0.0001%)
Carrier duty ± peak deviation is limited within the
15-9

WF1947/WF1948

15.7 Sweep Oscillation Mode
allowable range of duty for each carrier waveform.

15.7

Sweep Oscillation Mode

15.7.1 General
Sweep type

Frequency, phase, amplitude, DC offset, and duty

Sweep function

One way (lump waveform), two way (triangular wave)(switch)Linear, logarithmic (switch)
Common regardless of sweep type
However, logarithmic can use only frequency sweep

Sweep range settingSpecify starting value and stopping value, or center value
and span value.
However, the center value is also a simple average during
frequency logarithmic sweep
Assigning to a center value of a marker value is possible(vice versa).

Setting range of Sweep Time

0.1ms to 10,000s (resolution 4 digits or 0.1ms)
Common regardless of sweep type

Sweep Mode

Continuous, single, gated single (switch)
Common regardless of sweep typeFor gated single, it oscillates only during running sweep
However, when the waveform is DC, gated single is notavailable.

Operation

Start, stop, hold, resume, starting value output, stopping
value output

Trigger source (used for single sweep and gated sweep)
CH1: Internal, CH1 external input terminal (switch)
CH2: Internal, CH1 and CH2 external input terminal(switch)(CH1 external input on CH2 is enabled only when
external input is selected on CH1.)
Common regardless of sweep type
Trigger delay setting is invalid
Manual trigger available
Internal trigger oscillator for sweep (used for single sweep and gated sweep)
Period setting range

100.0µs to 10,000s (resolution 5 digits or 0.1µs)

Stop level setting (used for gated single sweep)
Function

Specify the signal level when gated single-shot sweep isstopped.

Setting range-100.00% to +100.00% (amplitude full-scale reference
and resolution 0.01%) or off
When stop level is set to off, stops by set starting
oscillation/stop phase
15-10

WF1947/WF1948

15.7 Sweep Oscillation Mode
Common regardless of sweep type
Remarks

When the waveform is Noise, oscillation start/stop phaseis invalid, stop level is always valid.
When the waveform is DC, oscillation start/stop phase isinvalid, stop level is invalid.
For phase sweep, sweep starting value is oscillation startphase and sweep stop value is oscillation stop phase

Oscillation stop unit when gated single One wave, 0.5 wave (switch)
Sweep synchronization/marker output
Marker off at one-way

Low level from sweep staring time to half of sweep time
Otherwise, high level

Marker off at two-way

Low level from sweep staring time to sweep stop time
Otherwise, high level

Marker on

Low level from sweep staring time to marker value
Otherwise, high level

Output connector

Shared with synchronization/sub-out connector

Sweep X drive output
Output voltage

0V to +3V/open
During sweep value rising, 0 to +3V, during falling, +3 to
0V

Output connector

Shared with synchronization/sub-out connector

Sweep outside trigger input (used for single sweep and gated sweep)
Polarity

Positive, negative, disable (switch)

Input connector

External trigger input is used
Input signal and input impedance depend on external
trigger input specification

Signals Selectable for Synchronization/Sub-output
Reference phase synchronization
Sweep synchronization/marker
Sweep X drive

15.7.2 Frequency Sweep
Waveform

Standard waveform except for noise, pulse wave, and DC
and an arbitrary waveform.

Setting range of start andstop frequency

0.01µHz to 30MHz (resolution 0.01µHz)
Limited within the allowed setting range of frequency foreach waveform.

15.7.3 Phase Sweep
Waveform

Standard waveform except for noise and DC and an
arbitrary waveform.
15-11

WF1947/WF1948

15.8 Burst oscillation mode
Setting range of start and stop phase-1800.000° to 1800.000°(resolution 0.001°)
Remarks:

The setting value is same as the phase setting

for other oscillation mode

15.7.4 Amplitude Sweep
Waveform

Standard

waveform

except

for

DC

and

arbitrary

waveform.
Setting range of start and stop amplitude

0Vp-p20Vp-p/open
Limited within the allowed setting range of amplitude foreach waveform.

15.7.5 DC Offset Sweep
Waveform

Standard waveform and arbitrary waveform.

Setting range of start and stop DC offset-10V to +10V/open
Limited within the allowed setting range of DC offset foreach waveform.

15.7.6 Duty Sweep
Waveform

Square wave and pulse wave

Setting range of start and stop duty
Rectangular wave
Duty variable range standard 0.0100% to 99.9900% (resolution 0.0001%)
Duty variable range extend
Pulse wave

0.0000% to 100.0000% (resolution 0.0001%)
0.0170% to 99.9830% (resolution 0.0001%)
Limited within the allowed setting range of duty for eachwaveform.

15.8

Burst oscillation mode

Burst mode
Auto burst

Repeats oscillating the number of mark wave and stopping
the number of space wave. Trigger becomes invalid.

Trigger burst

Oscillates the number of mark wave with synchronizing

trigger.
Gate

Oscillates integral multiple of integer cycle or half cyclewith synchronizing the gate signal.
However, when the waveform is noise, it makes
oscillation on/off by the gate signal.

Trigger gate

Gate oscillation making gate on/off based on each trigger.

Target waveform
Auto and trigger burst

Standard waveform except for noise and DC and an
arbitrary waveform.

Auto and trigger gate

Standard

waveform
15-12

except

for

DC

and

arbitrary

WF1947/WF1948

15.8 Burst oscillation mode
waveform.
Mark wave number setting range

0.5 to 999,999.5, 0.5 wave unit

Number of space wave setting range

0.5 to 999,999.5, 0.5 wave unit

Stop oscillation unit at gate

One wave, 0.5 wave (switch)

Setting range of start/stop oscillate-1800.000° to +1800.000° (resolution 0.001°)
Remarks:

The setting value is same as the phase setting

for other oscillation mode
Stop level setting range
Function

Specify the signal level while oscillation is stopped

Setting range-100.00% to +100.00% (amplitude full-scale reference
and resolution 0.01%) or off
When stop level is set to off, stops by set starting
oscillation/stop phase

Remarks

The waveform is Noise, oscillation start/stop phase isinvalid, stop level is always valid.

Trigger source (used for trigger burst)
CH1: Internal, CH1 external input terminal (switch)
CH2: Internal, CH1 and CH2 external input terminal(switch)(CH1 external input on CH2 is enabled only when
external input is selected on CH1.)
Manual trigger available
Internal trigger oscillator for burst (used except for auto burst)
Phase setting range
Trigger delay setting range

1.0µs to 1,000s (resolution 5 digits or 0.1µs)
0.00µs to 100.00s (setting resolution 8 digits or 0.01µs)
External delay 0.55µs
Enabled only for trigger burst (disabled for gate andtriggered gate)

Trigger jitter1ns rms or less typ.

Burst synchronization output
Polarity

Low level during oscillation, otherwise high level

Output connector

Shared with synchronization/sub-out connector

Signals Selectable for Synchronization/Sub-output
Reference phase synchronization
Burst synchronization

15-13

WF1947/WF1948

15.9 Triggers

15.9

Triggers

External
Application

Used for single sweep, gated single sweep, trigger burst,
gate, trigger gate

Input voltage

TTL level (low level 0.8V or lower, high level is 2.6V or
higher)Maximum allowable input*1

Polarity-0.5V+5.5V
Positive, negative, disable (switch)
FSK, PSK, sweep (each is independent setting)Minimum pulse width

*1

50ns

Input impedance

10k (pull-up to+3.3V), unbalanced

Input connector

Front panel (WF1947)/ rear panel (WF1948), BNC
receptacle

Manual trigger

Panel key operation

Application

Used for single sweep, gated single sweep, trigger burst,
gate, trigger gate

Internal trigger oscillation
For sweep, burst, and independent among channels
See the internal trigger oscillation in each section

15.10 Other I/Os
External 10 MHz frequency reference input
Select frequency reference

Enabled and disabled of external reference (switch)

Input voltage

0.5Vp-p5Vp-p

Maximum allowable input*1

10Vp-p

Input impedance

1k, unbalanced, AC coupling

Input frequency

10MHz (±0.5%(±50kHz))

Input waveform

Sine or square wave (50±5% duty)

Input connector

Back panel, BNC receptacle

Frequency reference output (WF1947 and WF1948, to synchronize more than one device)
Output voltage

1Vp-p/50 Square wave

Output impedance

50 , AC coupling

Output frequency

10MHz

Output connector

Back panel, BNC receptacle

External addition input
Additional gain

0.4 times, 2 times, 10 times, off (switch)
When 0.4 times is used, maximum output voltage range isfixed to 0.8Vp-p, when 2 times 4Vp-p, and when 10 times
20Vp-p.
During external modulation, it is dedicated to external
modulation input.
15-14

WF1947/WF1948

15.10 Other I/Os
Input voltage
Maximum allowable input-1V+1V*1±2V

Input frequency

DC10MHz (-3dB)

Input impedance

Balanced/10k, Unbalanced

Input connector

Front panel (WF1947)/ rear panel (WF1948), BNC
receptacle
Shared with external modulation input. Cannot be usedwith external modulation and external addition at a time.

15-15

WF1947/WF1948

15.11 2-Channel Coordination (WF1948 Only)

15.11 2-Channel Coordination (WF1948 Only)
Channel mode
Channel mode
Independent
2 phaseConstant frequency
difference

Constant frequency
ratio

Differential output

ActionIndependent setting
Keeps same frequency. Also controls to keep same frequency forfrequency sweep, internal frequency modulation, and internal FSK.
External frequency modulation and external FSK is not allowed.
Phase is independent setting among each channel.
Keep Difference of frequency constant. Also controls to keepfrequency difference for frequency sweep, internal frequency
modulation, and internal FSK.
External frequency modulation and external FSK is not allowed.
Keep Ratio of frequency constant. Also controls to keep frequency
ratio for frequency sweep, internal frequency modulation, andinternal FSK.
External frequency modulation and external FSK is not allowed.
Same frequency, amplitude, DC offset. Reverse phase waveform.
Controls to keep different output, even for each type of sweep andinternal modulation. External modulation is not allowed. External
addition is not allowed.

Common restriction conditions for 2 phase, constant frequency difference, constant frequency
ratio, and differential output•Oscillates on the same oscillation mode (for modulation oscillation, modulation type is alsosame. For sweep oscillation, sweep type is also same).
•Applies to standard waveform except for noise and DC and an arbitrary waveform.
•Burst, gated sweep is unavailable.
Same value setting and operation

CapableFrequency difference setting range

0.00µHz to 30MHz or less (resolution 0.01µHz)
CH2 frequency - CH1 frequency

Frequency ratio N:M setting range

1 to 9,999,999 (each of N and M)
N:M = CH2 frequency: CH1 frequency
Frequency resolution is limited to N × 0.01µHz for CH1,
M × 0.01µHz for CH2 (also for frequency sweep,
internal frequency sweep, and internal FSK)

Phase synchronization

Auto run when the channel mode is changed

Interval between channels for 2 phase±20ns or lower *1 , ±10ns or lower typ.
Conditions: Same waveform (sine wave and square wave)

15-16

WF1947/WF1948

15.12 Synchronization of Multiple Units

15.12 Synchronization of Multiple Units
Connection
Connection Method 1
Master unit

Externalreference
can be used

Slave unit

Slave unit

50Ω
termination
resistorTeeconnectorTeeconnector

Slave unit

Connection Method 2
Master unit

Slave unit

Slave unit

Externalreference
can be used

Connection cables
Cable type

Characteristic impedance 50  series coaxial cable with
BNC connector (RG-58A/U etc.)

Restriction to cable length
Maximum connection number

1 m or less between units, total cable length is 3 m or lessConnection Method 1: 6 units including master unit
Connection Method 2: 4 units including master unit

Phase synchronization

Manual operation

Interval of waveforms among equipments
Delay of each channel against each of a master equipment on the Nth slave equipment (1N)
Connection Method 1: 31ns+(N-1) x 6ns within ±25ns typ.
Connection Method 2: 31ns+(N-1) x 31ns within ±25ns
typ.
Conditions: Continuous oscillation, same frequency, same
phase, same waveform (sine wave and squarewave), load 50, DC offset setting 0V, amplitudesetting 10Vp-p/50, and connecting cable lengthof frequency reference output between externalfrequency reference input is 1m (RG-58A/U)

15-17

WF1947/WF1948

15.13 User-defined unit

15.13 User-defined unit
FunctionSet and display settings in any unit based on a specified
conversion expression

Setting target

Frequency (Hz), period (sec), amplitude (Vp-p, Vpk), DC
offset (V), phase (deg), and duty (%)

Conversion formula[(setting target value) + n] x m, or[log10(setting target value) + n] x mSpecify a conversion expression and values of n and m

Unit name string

Maximum 4 characters

15.14 Other Functions
Setting save memory

10 sets (saved in non-volatile memories)

Parameter setting at power-on
operation

Power-off with front panel operation→ It is restored at power-on to the previous operation
state
Shut down with power line disconnect→ The contents of setting memory number 1 are set

Output On/Off setting at power-on operation. Last State, On, Off, switch
Power OffmethodPower-On Output setting
Last State

On

Off

Panel power
supplyOff operation

Power Off
it is restored
the state
just before

Output On

Output Off

Shot downwith line

Output Off

Output On

Output Off

External Control Interface

GPIB, USBTMC

External control command

SCPI-1999/IEEE-488.2
and (WF194x compatible) own command

15-18

WF1947/WF1948

15.15 General Characteristics

15.15 General Characteristics
Indicator

3.5 inch TFT color LCD

I/O ground
Signal grounds for waveform output (FCTN OUT), synchronize/sub-output (SYNC/SUB
OUT), external modulation/add input (MOD/ADD IN) are insulated from the enclosure.
These signal grounds within same channel is common.
Signal ground for external 10MHz reference input (10MHz REF IN) is insulated from theenclosure.
Each signal ground for CH1, CH2, and 10MHz REF IN is independent.
Withstand voltage between the enclosure and insulated signal ground is maximum 42Vpk(DC+ACpeak).
The other signal grounds connects to the enclosure.
Power Supply
Power voltage range:

AC100V to 230V ±10% (250V or lower)

Power frequency range:

50Hz/60Hz

Power consumption

WF1947: 55VA or lower±2Hz

WF1948: 75VA or lower
Overvoltage category

II

Ambient temperature/humidity range conditions (See next image)
Guaranteed operation range
0°C+40°C, 585%RH
Furthermore, AH 1 to 25g g/m 3, no condensation
On some specifications, the temperature range limit ismore strict.
Altitude
2000m or lower
Storage conditions-10°C+50°C, 595%RH
Furthermore, AH 1 to 29g g/m 3, no condensation

Storageconditions

Guaranteed
operation range

Warm-up timeMore than 30 minutes typ.

Pollution degree

2 (indoor use)

External dimensions

216 (W) x 132.5 (H) x 288 (D) mm (without protrusions)
216 (W) x 149.5 (H) x 309 (D) mm

Weight(maximum dimension)

Approx. 2.6kg (accessories are not included. The weightof equipment)
15-19

WF1947/WF1948

15.15 General Characteristics
Safety and EMC (Applied only to models with the CE marking displayed on the rear panel)
EN 61010-1
EN 61326-1 (Group 1, Class A)
EN 61000-3-2
EN 61000-3-3
RoHS

Directive 2011/65/EU

15-20

WF1947/WF1948

Rear view

Front view

15-21
Surface treatment
Front panel: Plastic sheet Black4C
Frame:
Metallic gray paint
Cover:
Metallic gray paint

Cover surface details

When the stand is used

Side view

15.15 General Characteristics◼Outline dimensional drawing (WF1947)

WF1947/WF1948

Rear view

Front view

15-22

Cover surface details

Surface treatment
Front panel: Plastic sheet Black4C
Frame:
Metallic gray paint
Cover:
Metallic gray paint

When the stand is used

Side view

15.15 General Characteristics◼Outline dimensional drawing (WF1948)

WF1947/WF1948

15-23

CautionWhen mounting the unit in the rack, do not hold it only with the rack -mountadapters.
Be sure to hold the main unit with brackets or shelves on the rack side.

Surface treatment
Rack-mount adapter: Metallic gray paint15.15 General Characteristics◼Inch rack mount dimensional drawing (for 1 unit)

WF1947/WF1948

15-24

CautionWhen mounting the unit in the rack, do not hold it only with the rack -mountadapters.
Be sure to hold the main unit with brackets or shelves on the rack side.

Surface treatment
Rack-mount adapter: Metallic gray paintConnecting bracket dimensions(back side of enclosure)

Connecting
bracketdimensions

Connecting
bracketdimensions

15.15 General Characteristics◼Inch rack mount dimensional drawing (for 2 units)

WF1947/WF1948

15-25

CautionWhen mounting the unit in the rack, do not hold it only with the rack -mountadapters.
Be sure to hold the main unit with brackets or shelves on the rack side.

Surface treatment
Rack-mount adapter: Metallic gray paint15.15 General Characteristics◼Millimeter rack mount dimensional drawing (for 1 unit)

WF1947/WF1948

15-26

CautionWhen mounting the unit in the rack, do not hold it only with the rack -mountadapters.
Be sure to hold the main unit with brackets or shelves on the rack side.

Surface treatment
Rack-mount adapter: Metallic gray paintConnecting bracket dimensions(back side of enclosure)

Connecting
bracketdimensions

Connecting
bracketdimensions

15.15 General Characteristics◼Millimeter rack mount dimensional drawing (for 2 units)

WF1947/WF1948

WARRANTYNF Corporation certifies that this product was thoroughly tested and inspected and foundto meet its published specifications when it was shipped from our factory.
All NF products are warranted against defects in materials and workmanship for a periodof one year from the date of shipment. During the warranty period, NF will repair the defective
product without any charge for the parts and labor. For repair service under warranty, theproduct must be returned to either NF or an agent designated by NF. Purchaser shall prepay
all shipping charge, duties and taxes for the product to either NF or the agent from anothercountry, and shipping charge for the return of the product to purchaser shall be paid by NF
side.
This warranty shall not apply to any defect, failure or damage caused by a) improper use;b) improper or inadequate maintenance and care; or c) modification by purchaser or personnel
other than NF representatives.

NF Corporation────── REPAIR ──────

When a failure occurred and the product was found to be defective or you have any
uncertainty, please get in touch with NF Corporation or one of our representatives.
In such a case, let us know the model name (or product name), serial number (SERIAL No.
given on the nameplate), and symptom and operating conditions as detail as possible.
Though we will make efforts to reduce the repair period, when five or more years havepassed since you purchased the product, it may take time due to, for instance, the out of stockof repair parts.
Also, if the production of repair parts is discontinued, the product is extremely damaged, or the
product is modified, we may decline the repair.

NOTES• Reproduction of the contents of this manual is forbidden by applicable laws.
• The contents of this manual may be revised without notice.
• Information provided in this manual is intended to be accurate and reliable. However,
we assume no responsibility for any damage regarding the contents of this manual.
• Should you notice any doubtful or wrong statement, or lack of description, pleasecontact us or our agent.
©Copyright 2012-2022, NF Corporation

WF1947/WF1948 Instruction Manual (Operations)NF Corporation
6-3-20, Tsunashima Higashi, Kohoku-ku, Yokohama
223-8508 JAPAN
Phone +81-45-545-8128 Fax +81-45-545-8187

http://www.nfcorp.co.jp/

NF Corporation
6-3-20, Tsunashima Higashi, Kohoku-ku, Yokohama 223-8508 JAPAN