MULTIFUNCTION GENERATOR

WF1973/WF1974
Instruction Manual (Application)

NF Corporation

DA00016810-002

MULTIFUNCTION GENERATOR

WF1973/WF1974
Instruction Manual (Application)Preface
Thank you for purchasing the WF1973/WF1974 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 theequipment.

WARNING This mark indicates information for the avoidance of a hazard such as electric
shock that may endanger human life or cause injury during handling of theequipment.

CAUTION

This mark indicates information for the avoidance of damage to the equipment
during handling.

●This manual has the following chapter organization.
Instruction manuals of the WF1973/WF1974 are divided to two volumes, Basics andApplication. Instructions for remote control (GPIB and USB) are provided separately.
If reading this manual for the first time, start from 1. OVERVIEW of the Basics Instruction
Manual.
Basics
1. OVERVIEW
Briefly describes and explains the features and brief operation principles of the WF1973/
WF1974.
2. PREPARATIONS BEFORE USE
Describes various cautions regarding preparations to be made before using the WF1973/
WF1974, ranging from installation to connection of the power supply.
3. PANELS AND I/O TERMINALSDescribes the functions and operations of the switches and I/O terminals of the panel
controls.
4. BASIC OPERATION
Describes how to use basic functions.
5. SAVING AND RECALLING SETTINGS
Describes how to store and retrieve the settings.
6. LIST OF INITIAL SETTINGS
Describes initial settings.
7. SPECIFICATIONS
Lists the specifications (functions and performance) of the WF1973/WF1974.
Application
1. DETAILS OF PARAMETER-VARIABLE WAVEFORMS
Explains the meanings of each parameter of parameter-variable waveforms andwaveform examples.
2. CREATING ARBITRARY WAVEFORMS
Explains how to input and edit arbitrary waveforms from the panel control.

WF1973/WF1974

I3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)
Explains how to operate two channels at the same time.
4. SYNCHRONIZING MULTIPLE UNITS
Describes how to configure a multi-phase oscillator by connecting multiple units of thisproduct.
5. USING EXTERNAL FREQUENCY REFERENCE
Describes how to use external frequency reference.
6. USING SEQUENCE OSCILLATION
Describes how to set and operate sequence oscillation.
7. USING USER-DEFINED UNITS
Explains the units that can be optionally set by users.
8. OTHER UTILITY SETTINGS
Explains error messages and how to set display and operational details.
9. TROUBLESHOOTING
Explains error messages and how to respond to cases where a failure is suspected.
10. MAINTENANCE
Explains the operational inspection and performance test.

II

MULTIFUNCTION GENERATOR

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 product (with protective conductor terminal) that conforms to the JIS and
IEC insulation standards.
●Be sure to observe the contents of this instruction manual.
This instruction manual contains information for the safe operation and use of this product.
Be sure to read this information first before using this product.
All the warnings in the instruction manual must be heeded to prevent hazards that may
cause major accidents.
●Be sure to ground the product.
This product uses a line filter and must be grounded to avoid the risk of electric shock.
To prevent electric shock, be sure to safely implement grounding such that ground resistance is 100 Ω or lower.
The WF1973/WF1974 is automatically grounded when the 3-prong power plug is connected
to a 3-prong power outlet with a protective grounding contact.
This product does not come with a 3-prong to 2-prong conversion adapter. When using aseparately sold 3-prong to 2-prong conversion adapter, be sure to connect the (green)
grounding wire of the adapter to the grounding terminal next to the outlet.
●Check the power supply voltage.
This product operates on the power supply voltage shown in “2.3Supply Connection” in the Basics Instruction Manual.

Grounding and Power

Prior to connecting the power supply, check that the voltage of the power supply matches
the rated power supply of the product.
●In case of suspected anomaly
If this product emits smoke, an abnormal smell, or abnormal noise, immediately power it off
and stop using it.
If such an anomaly occurs, do not use this product until it has been repaired, andimmediately report the problem to the location of purchase (either NF Corporation or your
distributor).
●Do not use this product when gas is present.
An explosion or other such hazard may result.
●Do not remove the cover.
This product contains high-voltage parts. 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.
●Do not modify this product.
Absolutely never modify this product, as this may cause new hazards and may disqualify
this product from repair in case of failure.

WF1973/WF1974

III●Safety-related symbols
The general definitions of the safety-related symbols used on this product and in the
instruction manual are provided below.
Instruction Manual Reference SymbolThis symbol is displayed to alert the user to potential danger and referhim/her to the instruction manual.
Electric Shock Danger SymbolThis symbol indicates locations that present a risk of electric shock under
specific conditions.

WARNING Warning SymbolThis symbol indicates information for avoiding danger to human life orbodily injury while handling this product.

CAUTION

Caution SymbolThis symbol indicates information for preventing damage to the productwhen handling it.

●Other symbols
This symbol indicates that the external conductor of the connector isconnected to the case.

This symbol shows that the external conductor of the connector isinsulated from the case.
It shows, however, that the potential difference from the grounding
potential is restricted to 42 Vpk or lower for safety. (Since this product isgrounded when used, the potential of the case equals the grounding
potential.)●Waste disposal
To help ensure environmental protection, use a professional industrial waste contractor todispose of this product. A battery is not used for this product.

IV

MULTIFUNCTION GENERATORContents
Preface .................................................................................................................I
Safety Precautions..............................................................................................III
Contents ............................................................................................................. V
1. DETAILS OF PARAMETER-VARIABLE WAVEFORMS ................................1
1.1

Classification...................................................................................................... 1

1.2 Meaning of Each Parameter and Waveform Examples..................................... 2
1.2.1
Outline ..................................................................................................... 2
1.2.2
Steady sine group.................................................................................... 3
1.2.3
Transient sine group ................................................................................ 9
1.2.4
Pulse group............................................................................................ 13
1.2.5
Transient response group...................................................................... 19
1.2.6
Surge group ........................................................................................... 23
1.2.7
Other waveform group ........................................................................... 25

2. CREATING ARBITRARY WAVEFORMS .....................................................28
2.1

Basics .............................................................................................................. 28

2.2

Arbitrary Waveform Creating/Editing Screen Display Procedure andScreen Outline ................................................................................................. 29

2.3

Creating a New Arbitrary Waveform ................................................................ 30

2.4

Simple Arbitrary Waveform Creating Examples .............................................. 31

2.5

Outputting the Created Arbitrary Waveform .................................................... 32

2.6

Saving the Created Arbitrary Waveform .......................................................... 32

2.7

Identifying the Memory Capacity Required for Saving the Arbitrary
Waveform ........................................................................................................ 32

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY) ...........................34
3.1

Copying Settings Between Channels .............................................................. 35

3.2

Unifying Settings of 2 Channels....................................................................... 37

3.3

Phase Synchronization Between Channels..................................................... 38

3.4

Maintaining Both Channels to Same Frequency (2-Channel Ganged
Operation, 2-Phase) ........................................................................................ 39

3.5

Keeping Frequency Difference Constant (2-Channel Ganged Operation,
2-Tone) ............................................................................................................ 41

3.6

Keeping Frequency Ratio Constant (2-Channel Ganged Operation, Ratio).... 43

3.7

Obtaining Differential Output (2-Channel Ganged Operation, Differential)...... 45

4. SYNCHRONIZING MULTIPLE UNITS .........................................................46
4.1

Connection Procedure ..................................................................................... 46

4.2

Synchronization ............................................................................................... 48

WF1973/WF1974

V5. USING EXTERNAL FREQUENCY REFERENCE........................................50
5.1

Purpose of Using External Frequency Reference ........................................... 50

5.2

External Frequency Reference Signal Connection and Usage Procedures.... 50

6. USING SEQUENCE OSCILLATION ............................................................53
6.1

Sequence Oscillation Example ........................................................................ 53

6.2

Basics .............................................................................................................. 55

6.3

In-Step Processing Flow.................................................................................. 61

6.4

Setting and Manipulation Procedures.............................................................. 62

6.5

Screen Outline ................................................................................................. 66

6.6

Description of Step Control Parameters .......................................................... 68

6.7

Tips for Sequence Creation ............................................................................. 69

7. USING USER-DEFINED UNITS...................................................................72
7.1

Definition of User-Defined Unit ........................................................................ 72

7.2

Displaying and Setting User-Defined Units...................................................... 72

7.3

Defining User-Defined Units ............................................................................ 73

8. OTHER UTILITY SETTINGS........................................................................75
8.1

Selecting Remote Interface [Remote].............................................................. 75

8.2

Display Settings [Display] ................................................................................ 75

8.3

Modify Knob and Modify Direction Setting [Modify Direction] .......................... 75

8.4

Operation Sound Setting [Sound] .................................................................... 76

8.5

Self Check [Self Check] ................................................................................... 76

8.6

Product Information Display [Information]........................................................ 76

9. TROUBLESHOOTING..................................................................................77
9.1

Error Messages When Power Is Applied ......................................................... 77

9.2

Error Messages During Execution ................................................................... 78

9.3

Conflict Messages for Modulation.................................................................... 83

9.4

Conflict Messages for Sweep .......................................................................... 84

9.5

Conflict Messages for Burst............................................................................. 85

9.6

Compile Error Messages for Sequence........................................................... 86

9.7

Suspected Failure............................................................................................ 87

10. MAINTENANCE..........................................................................................88
10.1

Outline ........................................................................................................... 88

10.2

Operation Checks .......................................................................................... 90

10.3 Performance Tests ........................................................................................ 91
10.3.1 Frequency accuracy test........................................................................ 91
10.3.2 Sine wave amplitude accuracy test ....................................................... 92

VI

MULTIFUNCTION GENERATOR

10.3.3 DC offset accuracy test.......................................................................... 92
10.3.4 Sine wave amplitude/frequency characteristics test .............................. 93
10.3.5 Sine wave total harmonic distortion test ................................................ 94
10.3.6 Sine wave harmonic spurious test ......................................................... 94
10.3.7 Sine wave non-harmonic spurious test.................................................. 95
10.3.8 Square wave duty accuracy test............................................................ 95
10.3.9 Square wave rising/falling time test ....................................................... 96
10.3.10 Time difference between channels for 2-phase (WF1974 only) ............ 96

Index ..................................................................................................................97

WF1973/WF1974

VII

1.
1.1

DETAILS OF PARAMETER-VARIABLE WAVEFORMSClassification
Parameter-variable waveforms, which are of various types, are classified into six groups.
By selecting a waveform group in the parameter-variable waveform selection screen () “4.5Using Parameter-Variable Waveforms” in the Basics Instruction Manual), a waveform canbe selected for output from the waveforms in that group.

Select waveform group

Waveform polarity/amplitude
range

Parameter-variable waveform
selection screen

Select waveformfrom group

Variable parametersof waveform
Waveform graph

The six parameter-variable waveform groups are as described below.
The names of these groups are uniquely assigned exclusively for the equipment and forusage convenience. Similarly, all the waveform names and parameter names, except for afew, are uniquely assigned to the equipment. These names and the descriptions in thischapter do not restrict the way in which these waveforms are used.
■ Steady sine group
This group consists of waveforms created based on a sine wave. Repeated output of thesewaveforms is assumed.
■ Transient sine group
This group consists of waveforms created based on a sine wave. Use of these waveforms as 1
cycle of the start or end of a continuous sine wave during sequence oscillation is assumed.
■ Pulse group
This group consists of pulse waveforms.
■ Transient response group
This group consists of waveforms that simulate the system's transient response.
■ Surge group
This group consists of waveforms that simulate surge signals.
■ Other waveform group
This group consists of waveforms other than those of the above groups.

WF1973/WF1974

11. DETAILS OF PARAMETER-VARIABLE WAVEFORMS

1.2

Meaning of Each Parameter and Waveform Examples

1.2.1 Outline
Section 1.2 outlines the various waveforms, explains the meaning of each parameter, andshows waveform examples.
The waveforms examples show 1 cycle of the waveform written to the waveform memory.
The polarity of the waveform is normal. The amplitude range depends on the waveform, andis set to the amplitude range considered normal when using the waveform in question(initial setting value).
The vertical axis of ±1 corresponds to the amplitude full scale ±FS of the waveform memory.
The horizontal axis is the time axis. The time interval corresponding to one cycle is denotedby 1 unit. The horizontal axis is also the phase axis, ranging from 0° to 360°.
One cycle’s time is called “basic period”, and its reciprocal “basic frequency” in this manual.
These are respectively the oscillation period and the oscillation frequency of that entire
waveform.

Check
The waveform may disappear depending on the parameter settings.
If you do not know how to restore the waveform display, press the [Reset] soft
key in the center. This will return each parameter value to the factory default.
The polarity and amplitude range remain unchanged.

2

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.2 Steady sine groupa) Unbalanced sine (Unbalanced Sine)■ Outline
This is a sine wave whose amplitude can be set independently for the first half cycle andsecond half cycle.
Application examples:• Simulation of the output waveform of a system with different gains on the plus side andminus side
• Simulation of full-wave rectified waveforms and half-wave rectified waveforms■ Meaning of each parameter

Amptd1 = 70%

The following example is for the amplitude range of +1(+FS)±FS.
• First-half amplitude (Amptd1)
This is the amplitude of the first half cycle.
When 100%, the amplitude is that of theoriginal sine wave.

0

Variable range: −100.00% to 100.00%• Second-half amplitude (Amptd2)
This is the amplitude of the second half cycle.

–1(–FS)

When 100%, the amplitude is that of theoriginal sine wave.

0

0.5

1
Amptd2 = 40%

Variable range: −100.00% to 100.00%
Note that when the respective amplitudes are changed, the top and bottom peak values of
the waveform change.
Also note that when the first-half amplitude and second-half amplitude differ, the averagevalue of 1 cycle is not zero, so that a DC component results.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

Amptd1 = 100
Amptd2 = 50

WF1973/WF1974

Amptd1 = −50
Amptd2 = −100

Amptd1 = 100
Amptd2 = 0

Amptd1 = 100
Amptd2 = −1003

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Clipped sine (Clipped Sine)■ Outline
This is a sine wave having an amplitude with clipped top and bottom.
Application examples:• Simulation of waveforms clipped with an input clamp circuit• Simulation of amplifier output waveforms saturated with power supply voltage■ Meaning of each parameter

Clip = 30%

The following example is for the amplitude range of ±FS.
• Clip ratio (Clip)
This is the ratio of clipping of the top and bottomof the original sine wave.

+1(+FS)100%

The peak value of the original sine wave is 100%.
When the clip ratio is 0%, the waveform isthe original sine wave.

0

Variable range: 0.00% to 99.99%
100%

The peak value is fixed to ±FS.
–1(–FS)

0

0.5

1

Clip = 30%■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

Clip = 10

4

Clip = 20

Clip = 40

Clip = 80

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplesc) CF controlled sine (CF Ctrl Sine)■ Outline
This is a sine wave whose amplitude is extended, extracting only the neighborhood of 90°
and 270°.
Application examples:• Simulation of current waveform of capacitor input rectifier■ Meaning of each parameter

CF = 3

The following example is for the amplitude range of ±FS.
• Crest factor (CF)The crest factor is a value that expresses peak value/
RMS value. When this value is 1.41, the waveform isalmost identical to the original sine wave.
Variable range: 1.41 to 10.00+1(+FS)

0

The peak value is fixed to ±FS.
–1(–FS)00.5

1■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

CF = 1.5

WF1973/WF1974

CF = 2

CF = 3

CF = 55

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSd) Conduction angle controlled sine (Angle Ctrl Sine)■ Outline
This is a sine wave obtained by extracting part of the back or the front of each half cycle of asine wave.
Application example:
・Simulation of thyristor control waveforms■ Meaning of each parameter
The following example is for the amplitude range of ±FS.
Positive angle:

Negative angle:

Angle = 120deg

Angle = –120deg+1(+FS)+1(+FS)00–1(–FS)

0.5

01

Angle = 120deg–1(–FS)

0

0.5

1

Angle = –120deg• Conduction angle (Angle)
When the conduction angle is positive, the waveform is obtained by extracting the
conduction angle from the back of each half cycle of a sine wave.
When the conduction angle is negative, the waveform is obtained by extracting theabsolute value of the conduction angle from the front of each half cycle of a sine wave.
Variable range: −180.00° to 180.00°
The amplitude of the original sine wave is fixed to ±FS. Note that the amplitude may drop
below ±FS depending on the value of the conduction angle.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

Angle = 45

6Angle = 150

Angle = –45

Angle = –150

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplese) Staircase sine (Staircase Sine)■ Outline
This is a staircase shaped sine wave.
Application example:
・Simulation of pseudo sine wave output waveform of UPS (uninterruptible power supply),etc.
■ Meaning of each parameter

Steps = 4

The following example is for the amplitude range of ±FS.

+1(+FS)• Steps (Steps)
This is the number of values. Shown in the example
on the right is a 4-value pseudo sine wave.
Variable range: 2 to 100

0The peak value is fixed to ±FS.

–1(–FS)00.5

1■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

Steps = 3

WF1973/WF1974

Steps = 4

Steps = 7

Steps = 87

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSf) Multi-cycle sine (Multi-Cycle Sine)■ Outline
This is a waveform consisting of multiple concatenated sine wave cycles.
Application example:• Substitution for burst wave
■ Meaning of each parameter

Cycles = 3

The following example is for the amplitude range
of ±FS.

+1(+FS)• Number of cycles (Cycles)
This is the number of cycles included in one
period of the basic cycle.
Variable range: 0.01 to 50.00

0Phase = 30deg• Start phase (Phase)This is the start position phase.
It is the phase at the frequency of the basic
frequency multiplied by the above number ofcycles.

–1(–FS)

00.5

1Variable range: −360.00° to 360.00°
The peak value is fixed to ±FS.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

Cycles = 3
Phase = 08

Cycles = 2.5
Phase = 0

Cycles = 3
Phase = −90

Cycles = 2.5
Phase = −90

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.3 Transient sine groupa) On-phase controlled sine (On-Ph Ctrl Sine)■ Outline
This is a sine wave with a slope into on state.
Application example:• Simulation of output waveform of AC power supply device whose rising/falling time islimited■ Meaning of each parameter
The following example is for the amplitude range of ±FS.

+1(+FS)• Complete-on phase (OnPhase)
The original sine wave starts from this phase.
0

Variable range: 0.00° to 360.00°• On-slope time (SlopeT)
The amplitude changes linearly over this time, fromzero level until the complete-on phase amplitude.
–1(–FS)
0
Variable range: 0.00% to 50.00% of basic period
The amplitude of the original sine wave is fixed to ±FS.
Note that the amplitude may drop below ±FS dependingon the value of the complete-on phase.

0.5

1OnPhase = 90deg
SlopeT = 15%■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OnPhase = 90
SlopeT = 10

WF1973/WF1974

OnPhase = 120
SlopeT = 20

OnPhase = 150
SlopeT = 20

OnPhase = 270
SlopeT = 109

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Off-phase controlled sine (Off-Ph Ctrl Sine)■ Outline
This is a sine wave with a slope into off state.
Application example:• Simulation of output waveform of AC power supply device whose rising/falling time islimited■ Meaning of each parameter

SlopeT = 15%

The following example is for the amplitude range of±FS.

OffPhase = 270deg+1(+FS)• Off-phase (OffPhase)
The original sine wave ends at this phase.
Variable range: 0.00° to 360.00°• Off-slope time (SlopeT)
The amplitude changes linearly over this time, fromthe off-phase amplitude to zero level.
Variable range: 0.00% to 50.00% of basic period
The amplitude of the original sine wave is fixed to ±FS.
Note that the amplitude may drop below ±FS dependingon the value of the off-phase.

0–1(–FS)00.5

1■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OffPhase = 90
SlopeT = 10

10

OffPhase = 210
SlopeT = 20

OffPhase = 240
SlopeT = 20

OffPhase = 270
SlopeT = 10

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplesc) Chattering-on sine (Chattering-On Sine)■ Outline
This is a sine wave with chattering into on state.
Application example:• Simulation of output waveform of AC power supply device with switch or relay chattering
at output start.
■ Meaning of each parameter

ChatterN = 3

The following example is for the amplitude range of ±FS.
+1(+FS)• On-phase (OnPhase)
The original waveform starts coming in withchattering from this phase. Before that, it is fixed tozero.
Variable range: 0.00° to 360.00°

0• Number of chatterings (ChatterN)This is the number of on/off switchings. The first stateis on. On and off are repeated each with the same –1(–FS)
0duration.

1

0.5
Toff = 6%

Variable range: 0 to 3

Ton = 2%• On-state time (Ton)This is the on time for one chattering.

OnPhase = 30deg

Variable range: 0.00% to 20.00% of basic period• Off-state time (Toff)
This is the off time for one chattering.
Variable range: 0.00% to 20.00% of basic period
The amplitude of the original sine wave is fixed to ±FS. Note that the amplitude may drop
below ±FS depending on the parameter settings.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OnPhase = 30
ChatterN = 0
Ton = 2
Toff = 6

WF1973/WF1974

OnPhase = 30
ChatterN = 1
Ton = 2
Toff = 6

OnPhase = 30
ChatterN = 2
Ton = 2
Toff = 6

OnPhase = 30
ChatterN = 3
Ton = 2
Toff = 6

111. DETAILS OF PARAMETER-VARIABLE WAVEFORMSd) Chattering-off sine (Chattering-Off Sine)■ Outline
This is a sine wave with chattering into off state.
Application example:• Simulation of output waveform of AC power supply device with switch or relay chattering
when output is stopped■ Meaning of each parameter

OffPhase = 230deg

The following example is for the amplitude range of±FS.

Toff = 6%
Ton = 2%

+1(+FS)• Off-phase (OffPhase)
The original sine wave starts cutting off fromthis phase with chattering.

Variable range: 0.00° to 360.00°
0• Number of chattering (ChatterN)This is the number of on/off switchings. The firststate is off. On and off are repeated each withthe same duration.

–1(–FS)

Variable range: 0 to 3
• On-state time (Ton)This is the on time for one chattering.

0

0.5

1

ChatterN = 3

Variable range: 0.00% to 20.00% of basic period• Off-state time (Toff)
This is the off time for one chattering.
Variable range: 0.00% to 20.00% of basic period
The amplitude of the original sine wave is fixed to ±FS. Note that the amplitude may drop
below ±FS depending on the parameter settings.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OffPhase = 230
ChatterN = 0
Ton = 2
Toff = 6

12

OffPhase = 230
ChatterN = 1
Ton = 2
Toff = 6

OffPhase = 230
ChatterN = 2
Ton = 2
Toff = 6

OffPhase = 230
ChatterN = 3
Ton = 2
Toff = 6

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.4 Pulse groupa) Gaussian pulse (Gaussian Pulse)■ Outline
This is a Gaussian distribution waveform.
■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.

0.6065࡮FS• Standard deviation (Sigma)
This is σ of the Gaussian function.

0

Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS at the center of thehorizontal axis.

–1(–FS)0
0.5
1
The start and end do not decrease all the way down to
Sigma
=
10%
zero. Note that the larger the standard deviation, thehigher the start and end are above the zero level. In thecase of a standard deviation of 16.47% or lower, the start is 0.01•FS or lower.

■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Sigma = 5

Sigma = 10

Sigma = 15

Sigma = 20

■ Remark
The half value of the width is 2 ⋅ Sigma ⋅ 2 ⋅ ln ( 2 ) ≅ 2.35 ⋅ Sigma (%).
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).

2
100
y = FS ⋅ exp ⎛⎝ – 1--- ⋅ ⎛⎝ ------------------ ⋅ ( x – 0.5 )⎞⎠ ⎞⎠2 Sigma

WF1973/WF1974

13

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Lorentz pulse (Lorentz Pulse)■ Outline
This is a Lorentz waveform.
■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.
• Half value of width (HalfWidth)
This is the half value of the width of the Lorentz
function.

0.5࡮FS
0

Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS at the center of the–1(–FS)
horizontal axis.
0.5
01
HalfWidth=20%
The start and end do not decrease all the way down to
zero. Note that the larger the half value of the width, thehigher the start and end are above the zero level. In the case of a half value of the width of
10.05% or lower, the start is 0.01・FS or lower.
■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

HalfWidth = 5

HalfWidth = 10

HalfWidth = 15

HalfWidth = 20

■ Remark
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).

1
y = FS ⋅ ----------------------------------------------------------------------------2200
1 + ⎛⎝ -------------------------------- ⋅ ( x – 0.5 )⎞⎠HalfWidth

14

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplesc) Haversine (Haversine)■ Outline
This is a Sin2 pulse. It is a waveform obtained by adding an offset signal on the range of−90° to 270° of a sine wave.
■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.
• Width (Width)
This is the width of 1 cycle of a sine wave in the rangeof −90° to 270°.

0

Outside this range, the level is fixed to zero.
Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS at the center of thehorizontal axis.

–1(–FS)

00.5
1
Width = 50%■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Width = 10

Width = 20

Width = 50

Width = 100■ Remark
The half value of the width is Width/2 (%).
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).
Width
200

In the range x = 0.5 ± ------------------ ,FS100
y = -------- ⋅ ⎛⎝ 1 + cos ⎛⎝ 2π ⋅ ------------------ ⋅ ( x – 0.5 )⎞⎠ ⎞⎠2
Width

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1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSd) Half-sine pulse (Half-Sine Pulse)■ Outline
This is a half-sine pulse, consisting of a half-cycle waveform in the range of 0° to 180° of asine wave.
■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.
• Width (Width)
This is the width of the range of 0° to 180° of a sine
wave.

0

Outside this range, the level is fixed to zero.
Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS at the center of thehorizontal axis.

–1(–FS)

00.5
1
Width = 50%■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Width = 10

Width = 20

Width = 50

Width = 100■ Remark
The half value of the width is 2 ⋅ Width /3 (%).
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).
Width
200

In the range x = 0.5 ± ------------------ ,100
y = FS ⋅ cos ⎛ π ⋅ ------------------ ⋅ ( x – 0.5 )⎞⎝ Width⎠16

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplese) Trapezoid pulse (Trapezoid Pulse)■ Outline
This is a trapezoid pulse.
■ Meaning of each parameter

UpperBase = 20%

The following example is for the amplitude range of
0/+FS.
+1(+FS)• Slope width (RiseFall)
This is the width of the hypotenuse.
Variable range: 0.00% to 50.00% of basic period0• Upper base width (UpperBase)This is the width of the upper base.
Variable range: 0.00% to 100.00% of basic period

The peak value is fixed to +FS at the upper base at the –1(–FS)
0center of the horizontal axis. Note that when [(Slope width×2) + Upper base width] exceeds 100%, the start and end
exceed zero.

0.5

1

RiseFall = 30%■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

RiseFall = 25
UpperBase = 50

WF1973/WF1974

RiseFall = 20
UpperBase = 20

RiseFall = 0
UpperBase = 20

RiseFall = 20
UpperBase = 017

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSf) Sin(x)/x (Sin(x)/x)■ Outline
This is a Sin(x)/x waveform. It is called sinc function.
■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of ±FS.
• Number of zero crossings (ZeroCross)This is the number of zero crossings on single side.
0

Variable range: 1 to 50
The peak value is fixed to +FS at the center of thehorizontal axis.

This waveform has a frequency band that is approxi- –1(–FS)
0mately the basic frequency multiplied by the number ofzero crossings.

0.5

1

ZeroCross = 5■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

ZeroCross = 2

ZeroCross = 5

ZeroCross = 10

ZeroCross = 20

■ Remark
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range ±FS).

sin ( 2π ⋅ ZeroCross ⋅ ( x – 0.5 ) )y = FS ⋅ ----------------------------------------------------------------------------------2π ⋅ ZeroCross ⋅ ( x – 0.5 )18

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.5 Transient response groupa) Exponential rise (Exponential Rise)■ Outline
This is a first-order LPF step response waveform.
Application example:• Simulation of first-order delay system’s step output waveform■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.
• Time constant (TC)This is the time constant of the exponential function.

0.632࡮FS

0

Variable range: 0.01% to 100.00% of basic period
The amplitude over infinite time is +FS. The end does not
rise up to +FS. Note that the larger the time constant, the –1(–FS)
0.5
0smaller the end value. When the time constant is 21.71%
or lower, the end is 0.99•FS or higher.
TC = 20%

1■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

TC = 5

TC = 10

TC = 20

TC = 50■ Remark
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).

y = FS ⋅ ⎛⎝ 1 – exp ⎛⎝ – 100---------- ⋅ x⎞⎠ ⎞⎠TC

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1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Exponential fall (Exponential Fall)■ Outline
This is a first-order HPF step response waveform.
Application example:• Simulation of first-order system’s step output waveform■ Meaning of each parameter+1(+FS)

The following example is for the amplitude range of
0/+FS.
• Time constant (TC)This is the time constant of the exponential function.

0.368࡮FS
0

Variable range: 0.01% to 100.00% of basic period
The start begins from +FS, but the end does not decrease
all the way down to zero. Note that the larger the time –1(–FS)
0.5
0constant, the larger the end offset. When the time
constant is 21.71% or lower, the end is 0.01•FS or lower.
TC = 20%

1■ Waveform examples
The Polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

TC = 5

TC = 10

TC = 20

TC = 50■ Remark
Letting the horizontal and vertical axes be x and y, respectively, this can be expressed withthe following formula (in the case of amplitude range 0/+FS).

y = FS ⋅ exp ⎛ – 100---------- ⋅ x⎞
⎝ TC ⎠

20

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplesc) Second-order LPF step response (2nd Ord LPF Step)■ Outline
This is the second-order LPF step response waveform.
Application example:• Simulation of step output waveform of transmission system with ringing or overshoot■ Meaning of each parameter

Fn = 10, Q = 5

The following example is for the amplitude range of
0/+FS.
• LPF natural frequency (Fn)
The frequency of the oscillation component is lower
than Fn.

+1(+FS)
FS/2
0

Variable range: 1.00 to 50.00 times basic frequency• LPF Q (Q)When Q = 0.5, the oscillation component disappears.
Variable range: 0.50 to 50.00–1(–FS)0

0.5

1

The amplitude over infinite time is FS/2. The peak value is lower than +FS.
■ Waveform examples
The polarity is normal and the amplitude range = 0/+FS for all the waveforms shown below.

Fn = 5Q = 0.5

Fn = 5Q=1

Fn = 10Q=5

Fn = 15Q = 20■ Remark
The oscillation frequency is expressed with the following formula (basic frequency as areference).
1 Fn ⋅ 1 – -------------2
4⋅Q

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1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSd) Damped oscillation (Damped Oscillation)■ Outline
This is an oscillation waveform whose amplitude is damped exponentially. An oscillation
waveform whose amplitude increases exponentially can also be generated.
Application example:• Simulation of pulse response waveform with oscillation■ Meaning of each parameter
The following example is for the amplitude range of ±FS.
When DampTC is positive

When DampTC is negative

OscFreq = 5

OscFreq = 5

DampTC = 20%

DampTC = –20%

+1(+FS)+1(+FS)00–1(–FS)00.5

1–1(–FS)0

0.5

1• Oscillation frequency (OscFreq)
Variable range: 0.01 to 50.00 times basic frequency• Damping time constant (DampTC)
When positive, the oscillation is exponentially damped with this time constant.
When negative, the oscillation increases exponentially with this time constant.
Variable range: –100.00% to 100.00% of basic period
When the damping time constant is positive, the peak value is fixed to +FS.
When the damping time constant is negative, the amplitude over infinite time is ±FS.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OscFreq = 5
DampTC = 1022

OscFreq = 10
DampTC = 20

OscFreq = 5
DampTC = –10

OscFreq = 10
DampTC = –20

MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.6 Surge groupa) Oscillation surge (Oscillation Surge)■ Outline
This is simulation of a surge waveform with damped oscillation.
This is a step response waveform of first-order HPF and second-order LPF cascadedconnection circuits.
Application examples:• Simulation of surge waveform superimposed on power supply• Simulation of inrush current waveform of power supply■ Meaning of each parameter

OscFreq = 10

The following example is for the amplitude range of ±FS.
• Oscillation frequency (OscFreq)
Variable range: 0.01 to 50.00 times basic frequency• Damping time constant (DampTC)
The amplitude of the oscillation component isdampened exponentially with this time constant.
Variable range: 0.01% to 100.00% of basic period

DampTC = 20%
TrailTC = 10%+1(+FS)

0• Trailing time constant (TrailTC)
This is the damping time constant excluding theoscillation component (time constant of first-order –1(–FS)
0
HPF)

0.5

1

Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS. Note that the amplitude also swings to the negative side.
■ Waveform examples
The polarity is normal and the amplitude range is ±FS for all the waveforms shown below.

OscFreq = 10
DampTC = 20
TrailTC = 5

WF1973/WF1974

OscFreq = 10
DampTC = 20
TrailTC = 30

OscFreq = 10
DampTC = 5
TrailTC = 20

OscFreq = 10
DampTC = 30
TrailTC = 20

23

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Pulse surge (Pulse Surge)■ Outline
This is the simulation of a pulsed surge waveform. It does not have an oscillation
component.
Application example:• Simulation of overvoltage waveform of automotive battery■ Meaning of each parameter
The following example is for the amplitude rangeof 0/+FS.

+1(+FS)• Rising time (Tr)This is the time during which the amplitude
rises from 10% to 90% of the peak value.

0.9࡮FS

0.1࡮FS

0

Variable range: 0.01% to 100.00% of basic
period–1(–FS)• Duration time (Td)0This is the pulse interval during which theT r = 15%
amplitude exceeds 10% of the peak value.

0.5

1
Td = 60%

Variable range: 0.01% to 100.00% of basic period
The peak value is fixed to +FS.
The end does not decrease all the way down to zero. The larger the duration time, the higher
the end is above the zero level.
■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Tr = 1
Td = 20

Tr = 20
Td = 50

Tr = 5
Td = 30

Tr = 5
Td = 80■ Remark
The waveform differs from the predefined waveform when the following condition is not
met: 1.839 (approx.) < Td / Tr.

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MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examples

1.2.7 Other waveform groupa) Trapezoid with offset (Trapezoid with Offset)■ Outline
This is a trapezoid wave with offset in the amplitude direction.
Application example:• Simulation of voltage and current waveforms of switching power supply circuit■ Meaning of each parameter

UpperBase = 30%

The following example is for the amplitude range of
0/+FS.
+1(+FS)• Leading delay (Delay)
This is the start position of the rise of the Offset = 60%
trapezoid wave.
Variable range: 0.00% to 100.00% of basic
period0• Rising-slope width (Rise)
This is the width of the rising portion.
Variable range: 0.00% to 100.00% of basic
period–1(–FS)0

0.5

Delay = 15%• Upper base width (UpperBase)This is the width of the upper base.

1

Rise = 15%
Fall = 20%

Variable range: 0.00% to 100.00% of basic period• Falling-slope width (Fall)
This is the width of the falling portion.
Variable range: 0.00% to 100.00% of basic period• Offset (Offset)
This is the amplitude direction offset of the entire trapezoid.
Variable range: 0.00% to 100.00%
The peak value is fixed to +FS at the upper base.
■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Delay = 15
Rise = 10
UpperBase = 20
Fall = 30
Offset = 0

WF1973/WF1974

Delay = 15
Rise = 40
UpperBase = 0
Fall = 0
Offset = 60

Delay = 15
Rise = 0UpperBase = 20
Fall = 30
Offset = 0

Delay = 20
Rise = 40
UpperBase = 0
Fall = 0
Offset = 025

1. DETAILS OF PARAMETER-VARIABLE WAVEFORMSb) Half-sine edge pulse (Half-Sine Edge Pulse)■ Outline
This is a pulse wave with variable leading-edge time, trailing-edge time, and pulse width
duty.
The rise and fall shapes are the same half-sine shape as the pulse wave of the standard
waveform (half cycle of sine wave). Since, during sequence oscillation, the pulse wave of thestandard waveform cannot be used, this waveform is used instead by loading it to anarbitrary wave.
■ Meaning of each parameter

Duty = 60%

The following example is for the amplitude rangeof 0/+FS.
• Leading-edge time (LE)This is the time during which the amplitude
rises from 10% to 90% of the peak value.

+1(+FS)

Variable range: 0.00% to 100.00% of basic
period0.9࡮FS
0.5࡮FS
0.1࡮FS

0• Trailing-edge time (TE)This is the time during which the amplitude
falls from 90% to 10% of the peak value.
–1(–FS)
00.5
1Variable time: 0.00% to 100.00% of basic
LE = 20%
TE = 15%
period• Duty (Duty)
This is the pulse width duty at which the amplitude is 50% or more of the peak value.
Variable range: 0.00% to 100.00%
The peak value is fixed to +FS.
■ Waveform example
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

LE = 10
TE = 20
Duty = 40

LE = 30
TE = 5
Duty = 60

LE = 10
TE = 10Duty = 20

LE = 10
TE = 0
Duty = 70■ Remark
The waveform differs from the predefined waveform when the following condition is notmet:( LE + TE ) ⋅ 0.85 ≤ Duty ≤ 100 – ( LE + TE ) ⋅ 0.85

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MULTIFUNCTION GENERATOR

1.2 Meaning of Each Parameter and Waveform Examplesc) Bottom referenced ramp (Bottom Referenced Ramp)■ Outline
This is a ramp waveform using the bottom level as reference.
■ Meaning of each parameter
The following example is for the amplitude range of
0/+FS.
• Symmetry (Symm)
This is the ratio of the rising portion.

+1(+FS)

0

Variable range: 0.00% to 100.00%
The peak value is fixed to +FS.
–1(–FS)

00.5
Symm = 30%

1■ Waveform examples
The polarity is normal and the amplitude range is 0/+FS for all the waveforms shown below.

Symm = 0

Symm = 50

Symm = 80

Symm = 100■ Remark
Except when the symmetry is 0%, the phase zero position is fixed to the bottom level.
On the other hand, in the case of a ramp wave of the standard waveform, the phase zero
position is fixed to the zero center position of the amplitude.
) “4.4.16 Setting the ramp wave symmetry” in the Basics Instruction Manual.

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2.
2.1

CREATING ARBITRARY WAVEFORMS

BasicsThere are two main arbitrary waveform creating methods:• Creating on a PC using the supplied arbitrary waveform editing software• Input of waveform data from the panel
Here, arbitrary waveform creation method using the main unit’s panel is explained.
At the outset, please familiarize yourself with the following points regarding the arbitrary
waveforms of this equipment.
■ 2 data formats
The arbitrary waveform data of this product is of the two following types.
• Array format
This consists of data strings corresponding to waveform memory addresses.
The array format is used when the waveform captured with an oscilloscope is used as
an arbitrary waveform as is.
The waveform captured with an oscilloscope can be transferred to the equipment using
the supplied arbitrary waveform editing software.
Array format data cannot be created/edited from the panel.
The array format wavelength ranges from 4 K to 512 Kwords (2n, n = 12 to 19).
• Control point format
A waveform is created by performing linear interpolation between specified points(control points).
The data values of individual memory address cannot be specified directly.
Relatively simple arbitrary waveforms can be created and edited manually from thepanel.
The number of control points used for control point format is between 2 and 10,000
points.
The time axis direction of created waveforms is fixed to 0 to 1 per cycle, and theamplitude axis to ±1 (equivalent to ±FS of waveform memory).
■ Arbitrary waveform saving location
Arbitrary waveform data is saved to the following two locations (separate from the 512
Kword output waveform memory). In the case of the WF1974, each memory is used incommon for both channels.
• Saving memory
This is non-volatile memory for saving arbitrary waveforms.
Up to 128 waveforms, for a total amount of 4 Mwords (8192 KB) of arbitrary waveform
data, can be saved.
Both array format and control point format data can be saved.
For the memory capacity required for saving, ) p. 32• Edit memory
This is volatile memory for creating control point format arbitrary waveforms. The
number of control points can be changed in the range of 2 to 10,000 points.

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MULTIFUNCTION GENERATOR

2.2 Arbitrary Waveform Creating/Editing Screen Display Procedure and Screen Outline

Creating or editing an arbitrary waveform from the panel is done by manipulating thedata in this edit memory. Only one waveform can be manipulated in the edit memory at
one time.
■ Selecting the arbitrary waveform to be output
When the output waveform is set to arbitrary waveform on the Oscillator setting screen, thewaveform to be output can be selected from the saved arbitrary waveforms. The waveformthat can be selected at this time is either a waveform in the saving memory described above,or the waveform in the edit memory.
The selected waveform is written to the output waveform memory of a maximum length of
512 Kwords.
When the edit memory is selected for the output waveform, the waveform currently being
created/edited appears as is in the output.

2.2

Arbitrary Waveform Creating/Editing Screen Display Procedure and Screen Outline

Arbitrary waveform creating and editing is done on the ARB Edit screen.

1. Press the MENU MENU key to display the
Select [ARB Edit]in the top menu
and then press
the ENTER key

top menu window. In this window, select[ARB Edit] and then press the ENTER
ENTER key to open the ARB Edit screen.

2. The ARB Edit screen features two different display formats. One is list display, in which

values are displayed lined up, and the other is graph display.
These two types of display can be switched with the tabs on the left end of the screen.
[Index] is the control point number, which starts from 0. The start is fixed to X = 0.000000,
and the end is fixed to X = 1.000000. The Y value of the start and end is the same value(same point).
When the output waveform is set to the arbitrary waveform in the edit memory, thewaveform currently being created appears in the output as is. If another waveform has
been set, press the [Apply] button and then the ENTER ENTER key to make the output
waveform setting the arbitrary waveform in the edit memory, so that the waveform
currently being created is output.

■ List display
In list display, the waveform currently being created and the list of control points are
displayed.
The shape of the waveform is created by setting the X and Y values of control points.
Waveform being
createdWaveform output
button

WF1973/WF1974

Control point list
[Index], [X], and [Y]29

2. CREATING ARBITRARY WAVEFORMS■ Graph display
In graph display, the waveform currently being created is displayed in large size. The X
value and Y value of the currently selected control point are also displayed.
Similarly to list display, the waveform is created by setting the X value and Y value of eachcontrol point.
The waveform display can be expanded both along the horizontal and vertical axes with theselected control point at the center of the display.

[Index] of control
point

X and Y values of
selected control point

Waveform
output button

Selected
control point

Expand/reduce
waveform
display alonghorizontal axis

Expand/reduce
waveform
display along
vertical axis

Currently
createdwaveform■ Soft keys
1st stage ([ ▼ 1/2] displayed at right end)[New]: Clears the edit memory and sets the initial status.
[Wfm Copy]: Copies the standard waveform to the edit memory.
[Recall]: Copies an already saved control point format arbitrary waveform to the edit
memory.
[Store]: Saves the waveform currently in the edit memory.
2nd stage ([ ▼ 2/2] displayed at right end)
[Index −1]: Decrements the [Index] value by 1.
[Index +1]: Increments the [Index] value by 1.
[Delete]: Deletes the selected control point.
[Insert]: Inserts a new control point in the center between the selected control point andthe preceding control point.

2.3

Creating a New Arbitrary Waveform

A new arbitrary waveform can be created using one of the three methods described below.
• Creating a completely new arbitrary waveform
First, press the [New] soft key to clear the edit memory. Then input the control points.
Creating examples are given on the following page.
• Creating an arbitrary waveform by editing the standard waveform
First, press the [Wfm Copy] soft key to copy the standard waveform to the edit memory.
Then edit the control points. The control point manipulation method is the same as
when creating a completely new arbitrary waveform.
However, the noise and DC of the standard waveform cannot be copied. Moreover,square waves and pulse waves are copied as ideal square waves that maintain duty.
• Creating an arbitrary waveform by editing a saved arbitrary waveform
First, press the [Recall] soft key to copy the saved control point format arbitrary
waveform to the edit memory. Then edit the control points. The control point
manipulation method is the same as when creating a completely new arbitrary
waveform.

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MULTIFUNCTION GENERATOR

2.4 Simple Arbitrary Waveform Creating Examples

2.4

Simple Arbitrary Waveform Creating Examples

Simple waveforms are actually created in this section. The descriptions are done using displays
in list format.
The arbitrary waveforms to be created are triangular waveforms such as the one shown below.
The number of control points of this waveform is 3. In this section, create the waveform with 2
control points first, then increase control points to 3 points.
+1

0

–1
0

0.25

0.75

1

1. When the [New] soft key is pressed and the number of control points is set to 2, thefollowing setting results.
Index

X

Y

0 0.000000 +0.00000
1 0.500000 +0.00000
2 1.000000 +0.00000

2. Change the Index = 1 setting to X = 0.25, Y = +1.
Index

X

Y

0 0.000000 +0.00000
1 0.250000 +1.00000
2 1.000000 +0.00000

3. Select the Y value field of the end line (Index = 2, X = 1) and then press the [Insert] softkey.
The control point with X = 0.625000, Y = +0.49998 is newly created. The values rounded
to 16-bit units are displayed as the Y values, assuming ±32767 to be ±1.
Index

X

Y

0 0.000000 +0.00000
1 0.250000 +1.00000
2 0.625000 +0.49998
3 1.000000 +0.00000

4. Change the Index = 2 setting to X = 0.75, Y = −1. This completes the procedure.
Index

WF1973/WF1974

X

Y

0 0.000000+0.00000

1 0.250000+1.00000

2 0.750000–1.00000

3 1.000000+0.0000031

2. CREATING ARBITRARY WAVEFORMS

Check
・Set each X value so that it is between the preceding and following control
points. Each X value cannot be set exceeding this range.
・The Y value will be rounded in 16-bit units.
・To change the Y value in step fashion, set the variation width of the adjacent X
values to the 0.000001 minimum.

2.5

Outputting the Created Arbitrary Waveform

Select the [Apply] button on the screen (in the case of the WF1974, a separate button for eachchannel), and then press the ENTER key.
The output waveform setting becomes the arbitrary waveform of the edit memory, and the
waveform currently being created is output.
If the output waveform is set to the arbitrary waveform of the edit memory, the waveform
currently being created appears as is in the output.

2.6

Saving the Created Arbitrary Waveform

Press the [Store] soft key to open the window for saving. Select the proper memory number (from1 to 128), and perform the saving operation. The waveform can also be named.

2.7

Identifying the Memory Capacity Required for Saving the Arbitrary Waveform

Up to 128 waveforms or 4 Mwords (8192 KB) can be saved in non-volatile memory.
The memory capacity required for saving each data of array format and control point format is
obtained with the following formulas in KB units.
Array format:(2 × wavelength (word) + 768) / 1024 (Digits below the decimal point are
rounded up.)Control point format: (8 × number of control points + 768) / 1024 (Digits below the decimal
point are rounded up.)
The memory capacity required for saving an arbitrary waveform in array format is shown below:
Waveform size

4 KW

8 KW

16 KW

32 KW

64 KW

128 KW 256 KW

512 KW

Memory capacity
required for saving

9 KB

17 KB

33 KB

65 KB

129 KB257 KB

1025 KB

513 KBThe memory capacity required for saving an arbitrary waveform in control point format isshown below:
Control point
Memory capacity
required for saving

32

2

10

100

300

1,000

2,000

5,000

10,000

1 KB

1 KB

2 KB

4 KB

9 KB

17 KB

40 KB

79 KB

MULTIFUNCTION GENERATOR

2.7 Identifying the Memory Capacity Required for Saving the Arbitrary WaveformOn the arbitrary waveform selection screen (common for storing and retrieving), the waveformnumber [No.], name [Name], and the following items are displayed.
• Data format [Type]: The waveform of the array format is displayed as [RAW] and the
waveform of the control point format is displayed as [Point].
The edit memory of No. 0 is saved in the control point format; therefore, [Point] isdisplayed.
• Memory capacity for saving [Size]: For the arbitrary waveforms of No. 1 to No. 128, thememory capacity used for saving is displayed in KB units. For the edit memory of No. 0,
the memory capacity required for saving is displayed in KB units.
• Total memory capacity for saving [Total Size]: Total memory capacity used for saving thecurrent arbitrary waveforms of No. 1 to No. 128 is displayed in KB units. The size of theedit memory of No. 0 is not included in the total capacity.
Data format

Memory capacity used
for saving

Total memory capacity
used for saving

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3.

HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)

The WF1974, which is a 2-channel device, each of the two channels can be used as an independent
oscillator, but both channels can also be used by linking their settings and operation.
The following functions specific to a 2-channel device are available.
•Parameter copy function
Copies the settings of one channel to the other channel.
The settings of each channel can also be interchanged. ) p. 35•Two-channel same value setting function
The same setting values, such as amplitude and DC offset, can be set for both channels.
Output on/off switching, etc., can also be performed simultaneously for both channels. ) p. 37•Phase synchronization function
Initializes the oscillation phase of each channel. This function is used in the continuous
oscillation mode during independent operation of the two channels. ) p. 38•Two-channel ganged function with 2-phase
Maintains the same frequency and synchronization relationship. Also controlled to maintainthe same frequency and synchronization relationship during frequency modulation andfrequency sweep. ) p. 39•Two-channel ganged function with constant frequency difference
Maintains a constant frequency difference, while the frequency can be changed. Also
controlled to maintain a constant frequency difference during frequency modulation andfrequency sweep.) p. 41•Two-channel ganged function with constant frequency ratio
Maintains a constant frequency ratio and synchronization relationship, while the frequency
can be changed. Also controlled to maintain a constant frequency ratio during frequency
modulation and frequency sweep. ) p. 43•Two-channel ganged function with differential output
Outputs a reverse phase waveform with the same frequency, amplitude, and DC offset. Also
controlled to maintain reverse-phase waveform during modulation and sweep. ) p. 45

34

MULTIFUNCTION GENERATOR

3.1 Copying Settings Between Channels

3.1

Copying Settings Between Channels

Copying of settings between channels is done on the Utility screen.
1. On the Utility screen, select [ParameterOn the Utility
screen, selectCopy] and then press the ENTER ENTER[Parameter Copy]
key.
and then press
the ENTER key.

The parametercopy window
opens.

Select the
copy direction.

2. The parameter copy window opens, so

select the [Copy Direction] field and thenpress the ENTER ENTER key.
The copy direction choice list opens.
One of three copy directions can beselected: [CH1 ⇒ CH2] for copying from
CH1 to CH2, [CH2 ⇒ CH1] from CH2 to
CH1, and [CH1 ⇔ CH2] for exchanging.
Select the desired direction and thenpress the ENTER ENTER key.

3. Next, select the parameters to be copied.

Select the parameters to be copied from [All Parameters] (all parameters) or theparameters of individual oscillation modes. In the case of the parameters of individual
oscillation modes, there are four choices, namely [Basic Parameters] (parameters ofcontinuous oscillation mode), [Modulation Parameters] (parameters of modulated
oscillation mode), [Sweep Parameters] (parameters of sweep oscillation mode), and[Burst Parameters] (parameters of burst oscillation mode).
Select the desired parameter type and then press the ENTER ENTER key to set the copy
target. [Copy] is displayed. Press the ENTER ENTER key again to deselect the copy target.
[Off] is displayed.
Copies all theparameters

WF1973/WF1974

Copies the modulation
and burst parameters35

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)

4. Once the above settings have been
completed, select [OK] at the bottom of
the window and then press the ENTER
ENTER key to execute copying.
To not execute copying, select [Cancel] at
the bottom of the window and then press
the ENTER ENTER key, or press the CANCELCANCEL key.
Select [OK] and thenpress the ENTER key
to execute copying.

■ Remark
Even if all parameters of [Basic Parameters], [Modulation Parameters], [Sweep
Parameters], and [Burst Parameters] are copied, the setting differs from that of copying [AllParameters].
The following items can be copied only when [All Parameters] is copied .
• Output on/off condition• Oscillation mode
• External addition setting• User-defined units• Output on/off setting at power-on• Waveform parameter settings of all waveforms (Copying [Basic Parameters] copies only
the waveform parameter setting of the current waveform)• Amplitude/DC offset setting or High level/low level setting

36

MULTIFUNCTION GENERATOR

3.2 Unifying Settings of 2 Channels

3.2

Unifying Settings of 2 Channels■ Procedure and operation
First, at the Utility screen, enable the 2-channel same value setting function.
Perform the settings of the items that you want to duplicate across the two channels. Whenthe settings for one channel are done, those same settings are applied to the other channel.
In addition to frequency, phase, amplitude, and DC offset, this applies also to oscillationmode, waveform, etc. Other settings that can also be unified for both channels include
output on/off, burst trigger, and sweep start/stop.
This function is enabled until the 2-channel same value setting function is switched off.
■ Switching 2-channel same value setting function on/off
The 2-channel same value setting function is switched on/off on the Utility screen.
On the Utility screen, select [Both] and then press the ENTER ENTER key to switch thefunction from [Off] to [On].
As a result, the 2-channel same value setting function is on.
To switch the function back to [Off], press the ENTER ENTER key again.
[Both] is displayed on thestatus display area.

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

On screens other than the Utility screen, the function can be switched on/off by pressing the[CH1/CH2] key for at least 2 seconds.

WF1973/WF1974

37

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)

3.3

Phase Synchronization Between Channels

Even when the same frequency and phase settings are applied to both channels through the 2channel same value setting function, the phase relationships of the output waveforms of the twochannels vary moment to moment. To match the phase between the two channels requires phasesynchronization.
Phase synchronization is used for independent operation of two channels (when the channel modesetting is [Indep] (independent)).
When phase synchronization by maintaining the same frequency or frequency ratio is required,
use the 2-channel ganged function. ) pp. 39, 43
For the synchronization of multiple units, ) p. 46■ Performing synchronization
On the Utility
screen,select[φSync] andthen press
the ENTER
key toexecutephase
synchronization

First, set the independent channel mode,and make the frequency setting the samefor both channels.
The synchronization operation is done on
the Utility screen. On this screen, select[φSync] and then press the ENTER ENTER
key to execute phase synchronization.
At this time, the oscillation stops briefly forboth channels, causing momentary phase
discontinuity.

[Channel Mode] is [Indep]■ Phase relationship after synchronization
Through synchronization, the oscillation phase of each channel is initialized. The phasedifference of the output waveform is the difference between the phase settings of eachchannel.
Even when synchronization has been executed, if the frequency is later changed, thesynchronization relationship is then lost. In this case, execute synchronization again if
necessary.
■ Operation limitations
The limitations listed in the following table apply to synchronization. Synchronization isused in the case of independent operation of two channels. Even if invalid, the oscillation ofboth channels stops momentarily when synchronization is performed.
Item

38

Limitation

Waveform

Invalid for noise, DC

Modulated oscillation mode

Invalid for FM, FSK

Sweep oscillation mode

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

Burst oscillation mode

Invalid

Sequence oscillation mode

Cannot be used

MULTIFUNCTION GENERATOR

3.4 Maintaining Both Channels to Same Frequency (2-Channel Ganged Operation, 2-Phase)

3.4

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

When the channel mode is [2Phase] (2-phase), if the frequency of Channel 1 is changed, thefrequency of Channel 2 is automatically adjusted accordingly while maintaining thesynchronization relationship between the two channels. The same applies during frequency
modulation and frequency sweep. However, burst oscillation and gated single-shot sweep cannot
be executed.
■ Selecting 2-channel ganged operation
Set [Channel Mode]to [2Phase].

This icon is displayed in
the status display area

On the Utility screen, set [Channel Mode](channel mode) to [2Phase] (2-phase)(normally, [Indep] (independent) is set).
As a result, 2-phase oscillation is set.
The frequencies of both channels become
the same and phase synchronization is
performed automatically. The synchronization relationship is maintained even if
the frequency is changed.
The same frequency and synchronization
relationships are controlled to be maintained even during frequency modulationand frequency sweep.
In the case of 2-phase oscillation,
frequency-related
settings
canbeperformed only for Channel 1.

■ Changing the phase difference between the two channels
On the Oscillator setting screen, the phase can be independently set for each channel. The
phase difference between channels is the difference between the respective phase settings.
Normally, the phase of the channel to be used as the phase reference, for example Channel
1, is set to 0°, and only the phase setting of Channel 2 is changed. At this time, the phasesetting of Channel 2 becomes the phase of Channel 2 using Channel 1 as reference. As
shown in the following figure, if the phase setting of Channel 2 is positive, Channel 2
precedes Channel 1. If the phase setting of Channel 2 is negative, Channel 2 follows
Channel 1.

CH1 waveform output(Phase setting = 0°)

CH2 waveform
outputPhase
Phase
setting = setting =Positive Negative

WF1973/WF1974

39

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)■ Operation limitations
To maintain the same frequency and synchronization relationship, the limitations listed in
the following table apply.
Item
Waveform
Modulatedoscillation
mode

Sweep
oscillation
mode

Limitation
Noise and DC cannot be used.

FM

FM for both channels. Common peak deviation.
The modulation source is internal only. Common internal
modulation waveform and internal modulation frequency.

FSK

FSK for both channels. Common hop frequency.
The modulation source is internal only. Common internal
modulation frequency.

PM

PM for both channels. Independent modulation setting for eachchannel.

PSK

PSK for both channels. Independent modulation setting for eachchannel.

AM

AM for both channels. Independent modulation setting for eachchannel.

DC offset
modulation

DC offset modulation for both channels. Independent modulation
setting for each channel.

PWM

PWM for both channels. Independent modulation setting for eachchannel.

Frequency sweep

Frequency sweep for both channels.
Common sweep function, sweep range, sweep time, and sweep
mode.
Gated single-shot sweep not possible.
Common trigger source and internal trigger oscillator for sweep
during single-shot sweep. The external trigger source is valid only
for CH1.

Phase sweep

Phase sweep for both channels. Independent sweep setting foreach channel.

Amplitude sweep

Amplitude sweep for both channels. Independent sweep setting foreach channel.

DC offset sweep

DC offset sweep for both channels. Independent sweep setting foreach channel.

Duty sweep

Duty sweep for both channels. Independent sweep setting for eachchannel.

Burst oscillation mode

Cannot be used.

Sequence oscillation mode

Cannot be used.

During modulation and sweep, both channels are set to the same type of modulation andsweep. If modulation (other than FM, FSK) and sweep (other than frequency sweep) are notrequired for the other channel, use that channel with its modulation width and sweep width
set to zero.

40

MULTIFUNCTION GENERATOR

3.5 Keeping Frequency Difference Constant (2-Channel Ganged Operation, 2-Tone)

3.5

Keeping Frequency Difference Constant (2-Channel Ganged Operation, 2-Tone)

When the channel mode is [2Tone] (two-tone), the frequency can be changed while maintaining thefrequency difference between the two channels. When the frequency of Channel 1 is changed, thefrequency of Channel 2 is automatically changed accordingly. The same applies during frequency
modulation and frequency sweep. However, burst oscillation and gated single-shot sweep cannot
be executed.
■ Selecting 2-channel ganged operation
Set [Channel Mode]to [2Tone]

This icon is displayed in
the status display area

On the Utility screen, set [Channel Mode](channel mode) to [2Tone] (2-tone)(normally, [Indep] (independent) is set).
As a result, fixed frequency difference
oscillation is set.
The frequency difference between the twochannels is maintained.
The same frequency difference iscontrolled to be maintained, even during
frequency modulation and frequency
sweep.
In the case of fixed frequency difference
oscillation, the frequency of Channel 2cannot be set directly.

■ Setting the frequency difference
Set the frequency of Channel 2
with [ΔFreq].

WF1973/WF1974

On the Oscillator setting screen, set thefrequency of Channel 2 with [ΔFreq].
The frequency of Channel 2 is the sum of
the frequency of Channel 1 and thatfrequency difference.

41

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)■ Operation limitations
To maintain the frequency difference, the limitations listed in the following table apply.
Item
Waveform
Modulatedoscillation
mode

Sweep
oscillation
mode

Limitation
Noise and DC cannot be used.

FM

FM for both channels. Common peak deviation.
The modulation source is internal only. Common internal
modulation waveform and internal modulation frequency.

FSK

FSK for both channels. Hop frequency according to frequency
difference.
The modulation source is internal only. Common internal
modulation frequency.

PM

PM for both channels. Independent modulation setting for eachchannel.

PSK

PSK for both channels. Independent modulation setting for eachchannel.

AM

AM for both channels. Independent modulation setting for eachchannel.

DC offset
modulation

DC offset modulation for both channels. Independent modulation
setting for each channel.

PWM

PWM for both channels. Independent modulation setting for eachchannel.

Frequency sweep

Frequency sweep for both channels.
Sweep range according to frequency difference.
Common sweep function, sweep time, and sweep mode.
Gated single-shot sweep not possible.
Common trigger source and internal trigger oscillator for sweep
during single-shot sweep. The external trigger source is valid only
for CH1.

Phase sweep

Phase sweep for both channels. Independent sweep setting foreach channel.

Amplitude sweep

Amplitude sweep for both channels. Independent sweep setting foreach channel.

DC offset sweep

DC offset sweep for both channels. Independent sweep setting foreach channel.

Duty sweep

Duty sweep for both channels. Independent sweep setting for eachchannel.

Burst oscillation mode

Cannot be used.

Sequence oscillation mode

Cannot be used.

During modulation and sweep, both channels are set to the same type of modulation andsweep. If modulation (other than FM, FSK) and sweep (other than frequency sweep) are notrequired for the other channel, use that channel with its modulation width and sweep width
set to zero.
The frequency difference of the hop frequency in FSK is limited by the setting resolution of
the hop frequency.
If logarithmic sweep is selected for frequency sweep, logarithmic sweep is executed for
Channel 1, but since Channel 2 follows with the fixed frequency difference, the sweep is notlogarithmic.

42

MULTIFUNCTION GENERATOR

3.6 Keeping Frequency Ratio Constant (2-Channel Ganged Operation, Ratio)

3.6

Keeping Frequency Ratio Constant (2-Channel Ganged Operation, Ratio)

When the channel mode is [Ratio] (ratio), the frequency can be changed while maintaining thefrequency ratio of the two channels. When the frequency of Channel 1 is changed, the frequency of
Channel 2 is automatically changed accordingly. The same applies during frequency modulationand frequency sweep. However, burst oscillation and gated single-shot sweep cannot be executed.
■ Selecting 2-channel ganged operation
Set [Channel Mode]to [Ratio].

This icon is displayed in
the status display area

On the Utility screen, set [Channel Mode](channel mode) to [Ratio] (ratio) (normally,[Indep] (independent) is set).
As a result, constant frequency ratio
oscillation is set.
The frequency ratio of the two channels ismaintained. The same frequency ratio iscontrolled to be maintained, even during
frequency modulation and frequency
sweep.
In the case of constant frequency ratio
oscillation, the frequency of Channel 2cannot be set directly.

■ Setting the frequency ratio
Set [Ratio(N)] and[Ratio(M)] for Channel 2

WF1973/WF1974

On the Oscillator screen, set thefrequency ratio with [Ratio(N)] and[Ratio(M)] for Channel 2.
The ratio of [frequency of Channel
2]:[frequency of Channel 1] becomes[N:M].
When the frequency ratio is changed, theoscillation stops briefly for both channels,causing momentary phase discontinuity.

43

3. HANDY USE OF 2-CHANNEL DEVICE (WF1974 ONLY)■ Operation limitations
To maintain the frequency ratio, the limitations listed in the following table apply.
Item
Waveform
Modulatedoscillation
mode

Sweep
oscillation
mode

Limitation
Noise and DC cannot be used.

FM

FM for both channels. Peak deviation according to frequency ratio.
The modulation source is internal only. Common internal
modulation waveform and internal modulation frequency.

FSK

FSK for both channels. Hop frequency according to frequency
ratio.
The modulation source is internal only. Common internal
modulation frequency.

PM

PM for both channels. Independent modulation setting for eachchannel.

PSK

PSK for both channels. Independent modulation setting for eachchannel.

AM

AM for both channels. Independent modulation setting for eachchannel.

DC offset
modulation

DC offset modulation for both channels. Independent modulation
setting for each channel.

PWM

PWM for both channels. Independent modulation setting for eachchannel.

Frequency sweep

Frequency sweep for both channels.
Sweep range according to frequency ratio.
Common sweep function, sweep time, and sweep mode.
Gated single-shot sweep not possible.
Common trigger source and internal trigger oscillator for sweep
during single-shot sweep. The external trigger source is valid only
for CH1.

Phase sweep

Phase sweep for both channels. Independent sweep setting foreach channel.

Amplitude sweep

Amplitude sweep for both channels. Independent sweep setting foreach channel.

DC offset sweep

DC offset sweep for both channels. Independent sweep setting foreach channel.

Duty sweep

Duty sweep for both channels. Independent sweep setting for eachchannel.

Burst oscillation mode

Cannot be used.

Sequence oscillation mode

Cannot be used.

During modulation and sweep, both channels are set to the same type of modulation andsweep. If modulation (other than FM, FSK) and sweep (other than frequency sweep) are notrequired for the other channel, use that channel with its modulation width and sweep width
set to zero.
Frequency ratios on peak deviation in FM and hop frequency in FSK are limited by each frequency setting resolution, respectively.

44

MULTIFUNCTION GENERATOR

3.7 Obtaining Differential Output (2-Channel Ganged Operation, Differential)

3.7

Obtaining Differential Output (2-Channel Ganged Operation, Differential)

When the channel mode is [Diff] (differential), the settings can be changed while maintaining thedifferential output of the two channels. When the settings of Channel 1 are changed, the settingsof Channel 2 are automatically changed accordingly. The same applies during various modulationsand various sweeps. However, burst oscillation and gated oscillation single sweep cannot be
executed.
■ Selecting 2-channel ganged operation
Set [Channel Mode]to [Diff].

This icon is displayed in
the status display area

On the Utility screen, set [Channel Mode](channel mode) to [Diff] (differential)(normally, [Indep] (independent) is set).
As a result, differential output oscillation isset.
The frequency, phase, amplitude, and DC
offset settings of the two channels are
made to match, and the output waveforms
are inverted.
The differential output relationship ismaintained even if the settings arechanged.
The differential output relationship is controlled to be maintained even during various modulation and various sweep.
In the case of differential output oscillation,
settings can be performed only for
Channel 1 (operation as oscillator of a single channel).

■ Operation limitations
To maintain differential output, the limitations listed in the following table apply.
Item

Limitation

Waveform

Noise and DC cannot be used.

Modulated oscillation
modeInternal modulation source only

Sweep oscillation mode

Gated single-shot sweep not possible. External trigger source of CH1 onlyis valid.

Burst oscillation mode

Cannot be used

Sequence oscillation
mode

Cannot be used

External addition

Cannot be usedCheck
The output DC offset of both channels has the same value and same polarity.
Differential output for AC, but not for DC.

WF1973/WF1974

45

4.

SYNCHRONIZING MULTIPLE UNITS

By synchronizing multiple WF1973 and WF1974 units, an oscillator of up to 12 phases (using six
WF1974 units) can be configured. The phase and amplitude can be independently changed for eachphase.
Set the same frequency for all the units and all the channels.

4.1

Connection Procedure

The WF1973 or WF1974 unit that serves as the synchronization reference is called the master
unit. The other WF1973 and WF1974 units are called slave units.
■ Connectors
Use the external 10 MHz frequency reference input (10MHz REF IN) and frequency
reference output (REF OUT) on the rear panel.
■ CableCable type: Coaxial cable of 50 Ω characteristic impedance with BNC connector(RG-58A/U, etc.)
Cable length restriction: 1 m max. between units, total length of 3 m max.
■ Connection method
One of two connection methods can be used (connection method 1 and connection method 2).
In the case of a large number of units, connection method 1 minimizes the time difference
between slave units. However, this method requires, in addition to coaxial cables, T dividers
and 50 Ω termination resistor.
Connection method 2 is simpler in that it allows connection using coaxial cables only.
However, the time difference between slave units is larger than for connection method 1.
Moreover, the maximum number of units that can be connected with this method is smaller
compared to connection method 1.
Either the internal crystal oscillator or an external 10 MHz clock can be used as thefrequency reference of the master unit. When an external 10 MHz clock is used as thereference, the frequencies of the slave units have the same accuracy as the externalreference.

46

MULTIFUNCTION GENERATOR

4.1 Connection Procedure• Connection method 1
Connect the reference output of the master unit in parallel to the reference inputs of theslave units using T dividers.
Use a 50 Ω termination resistor for the reference input of the end slave unit.
The time difference between the slave units depends on the length of the connection
cables (approx. 6 ns/m).
Up to 6 units (master unit + slave units) can be connected.
Slave unit

Master unit

Use ofexternalreferencepossible

10MHz
REF IN

REF
OUT

10MHz
REF IN

Slave unit

REF
OUT

T divider

10MHz
REF IN

Slave unit

REF
OUT

10MHz
REF IN

REF
OUT

50 Ω
termination
resistor

T divider• Connection method 2
Connect the reference outputs of the master unit or slave unit to the next-stage reference
input of the slave unit.
The time difference between the slave units depends on the internal unit delay (approx.
25 ns) and the connection cable length (approx. 6 ns/m).
Up to 4 units (master unit + slave units) can be connected.
Master unit
10MHz
REF INREF
OUT

Slave unit
10MHz
REF INREF
OUT

Slave unit
10MHz
REF INREF
OUT

Use ofexternalreferencepossible

WF1973/WF1974

47

4. SYNCHRONIZING MULTIPLE UNITS

4.2

Synchronization■ Before performing synchronization
Once the master unit and slave units have been connected, perform the following settings.
Master unit
• Set 2-channel independent operation or 2phase operation (set channel mode to [Indep](independent) or [2Phase] (2-phase) on the
Utility screen) (WF1974 only).

Set [Channel Mode] to [Indep] or[2Phase] (WF1974 only).

• If the frequency reference of the master unit isexternal, enable the external frequency
reference (set the external reference to[Enable] on the Utility screen). ) p. 50• Set the frequency of each channel to thefrequency used for the synchronized operationof the various units (same frequency setting
for all channels of all units).
Slave units• Set 2-channel independent operation or 2phase operation (set channel mode to [Indep](independent) or [2Phase] (2-phase) on the
Utility screen) (WF1974 only).

Set [Channel Mode] to[Indep] or [2Phase](WF1974 only).

Set [Ext Reference]to [Enable].

• Enable the external frequency reference (onthe Utility screen, set the external reference to[Enable]).
• Set the frequency of each channel to thefrequency used for the synchronized operationof the multiple units (same frequency setting
for all channels of all units).
Check that all the slave units operate with the external frequency reference. If the [Ref] iconin the status display area at the top of the screen is displayed without blinking, thisindicates operation at the external frequency reference.
[Ref] icon is displayed
without flashing in the caseof operation at the externalfrequency reference48

MULTIFUNCTION GENERATOR

4.2 Synchronization■ Performing synchronization
Synchronization is performed on the master unit.

On the Utility
screen, select[φSync] and thenpress the ENTER
key to perform
phase synchronization.

Synchronization is performed on the Utility
screen of the master unit.
On the Utility screen, select [φSync] andthen press the ENTER ENTER key toperform phase synchronization.
At this time, oscillation stops briefly for all
the channels, causing momentary phase
discontinuity.

Once phase synchronization is performed, a message is displayed on each unit.
■ Phase relationship after synchronization
Through synchronization, the oscillation phase of each channel is initialized. The phasedifference of the output waveform is the difference between the phase settings of eachchannel.
Even when synchronization has been executed, if the frequency is later changed, thesynchronization relationship is then lost. Even if the synchronization relationship is lost, no
message to this effect is displayed. In this case, execute synchronization again if necessary.
When the cables used to connect the master unit to the slave units, and the slave units toone another, are disconnected, the synchronization relationship is lost. The synchronization
relationship is also lost if the channel mode and the external frequency reference settings
are changed.
■ Operation limitations
The limitations listed in the following table apply to synchronization. Even if invalid, theoscillation of both channels stops momentarily when synchronization is performed.
Item

Limitation

Waveform

Invalid for noise, DC

Modulated oscillation
mode

Invalid for FM, FSK

Sweep oscillation mode

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

Burst oscillation mode

Invalid

Sequence oscillation
mode

Cannot be used

WF1973/WF1974

49

5.
5.1

USING EXTERNAL FREQUENCY REFERENCE

Purpose of Using External Frequency ReferenceThis equipment uses an internal crystal oscillator as the frequency reference, but can also use
an external 10 MHz clock for this purpose.
Generally, an external frequency reference is used for the following purposes.
• To increase frequency accuracy and stability through the use of a frequency reference thathas greater accuracy than the frequency reference built in this equipment (for example,
rubidium frequency standard)• To use a common frequency accuracy, by sharing the same frequency reference with otherunits• To obtain synchronization with other WF1973 or WF1974 units. For details on thesynchronization of multiple units, ) p. 46

5.2

External Frequency Reference Signal Connection and Usage Procedures■ Connecting a 10 MHz signal
Connect an external 10 MHz signal to the external 10 MHz frequency reference input(10MHz REF IN) BNC terminal on the rear panel.
WF1973

WF1974

10 MHz10 MHzThe input characteristics are as follows.
Input voltage

0.5 Vp-p to 5 Vp-p

Maximum allowed input

10 Vp-pInput impedance

1 kΩ, AC coupled

Input frequency

10 MHz (±0.5% (±50 kHz))

Input waveform

Sine wave or square wave (50 ±5% duty)

Signal GND

Insulated from housing and each channel's waveform output(42 Vpk max.)

The input impedance is not 50 Ω, so if reverberation seems likely to be a problem, use atermination resistor.

50

MULTIFUNCTION GENERATOR

5.2 External Frequency Reference Signal Connection and Usage Procedures

The external 10 MHz frequency reference input signal ground is insulated from the housing.
Therefore, the connection to the frequency standard is not influenced by noise caused by aground loop. Neither is there influence from noise caused by a ground loop in the case ofsynchronized connection of multiple WF1973 and WF1974 units.
However, in all cases, the floating voltage is limited to 42 Vpk (DC + AC peak) max. in order
to avoid electric shock.
For cautions on floating ground connection, ) “3.3 Cautions on Floating Ground
Connection” in the Basics Instruction Manual.

WARNING To prevent electric shocks, do not apply a voltage exceeding 42 Vpk (DC + ACpeak) between the ground of the BNC connectors insulated from the housing
and the housing.
Also, do not apply a voltage exceeding 42 Vpk (DC + AC peak) between the
grounds of the BNC connector groups insulated from the housing. "BNC
connector group," as used here, refers to multiple BNC connectors that areconnected to a common ground.
If such a voltage were to be applied, the internal voltage limiting elements will
try to curb the working voltage, but if the voltage is too large, equipment burnout
may result.

CAUTION

If there is a difference in potential between the ground of a BNC connector
insulated from the housing and the housing, do not short circuit the hot side ofthat BNC connector and the housing, as this may damage the equipment.

CAUTION

If a difference in potential exists between the grounds of the BNC connectors,
do not short circuit these BNC connector grounds, as this may damage theequipment.

■ Enabling the external frequency reference
The external frequency reference can be enabled/disabled on the Utility screen.
On the Utility screen, select [Ext Reference] and then press the ENTER ENTER key to switchfrom [Disable] to [Enable]. The external frequency reference is enabled as a result.
To go back to [Disable], press the ENTER ENTER key again.
On the Utility screen,
select [Ext Reference] andthen press the ENTER

If a usable frequency reference is input, [Valid] isdisplayed in the [10MHz Ref In] field.
If not, then [Invalid] is displayed.

WF1973/WF1974

51

5. USING EXTERNAL FREQUENCY REFERENCE

When the [Ext Reference] setting is [Enable] and the [10MHz Ref In] status is [Valid], thisproduct operates by using the signal input to the external 10 MHz frequency reference terminalas the frequency reference.
However, if the external frequency reference signal is interrupted at some point, the internalfrequency reference is automatically switched to. Then, if the external frequency reference
signal recovers, operation using the external frequency as the reference resumes.
Which signal is used as the frequency reference is always displayed in the status display area at
the top of the screen.
[Ref] icon is displayed if the current frequency reference is external.
If the reference input status is [Invalid], this icon blinks.

52

MULTIFUNCTION GENERATOR

6.
6.1

USING SEQUENCE OSCILLATION

Sequence Oscillation Example

As a simple example of sequence oscillation, let us set up a sequence that changes the DC
voltage in stages, as shown in the following figure.
(First, restore the initial settings on the Utility screen.)
20 s

10 s
Keep

+10 V
Sweep

Const

+5 V

Outputvoltage

5s

15 s

Auto
Hold

Sweep

0V
Time

Step 0

Step 1

Step 2

Step 3

Step 0Stop or Resume

Start

Set the sequence as follows.
Step No.

Step Control Parameters

Intra-Step Channel Parameters0Time: 5 s

StopPhs: Off

StepCode: Don’t care Fctn: DC
Offset: 0V

1

Time: 20 s

AutoHold: Off
StopPhs: Off
StateB: Off
EventB: Off

JumpTo: Off

AutoHold: Off
StopPhs: Off
StateB: Off
EventB: Off

JumpTo: Off

AutoHold: On
StopPhs: Off
StateB: Off
EventB: Off

JumpTo: Off

2

3

Time: 10 s

Time: 15 s

Action: Sweep

Fctn: DC
Offset: +10V Action: Sweep

StepTerm: Continue
StepCode: Don’t care
Fctn: DC
Offset:Action: Keep

StepTerm: Continue
StepCode: Don’t care
Fctn: DC
Offset: +5 V Action: Const

StepTerm: End
StepCode: Don’t care

The operation is described below using the step sequence.
Step 0
These are the output settings before the sequence starts and after the sequence ends.
In this case, in the DC 0 V state, the system waits for the sequence to start.
Since [Time] and [Action] are valid only when the sequence is stopped, they will be
explained later.

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6. USING SEQUENCE OSCILLATION

Step 1
When the sequence starts, the sequence goes to Step 1. Since [Time] is 20 s, [Offset] is +10 V,
and [Action] of [Offset] is [Sweep], the output voltage rises linearly from 0 V to +10 V over
20 s.
Once +10 V has been reached after 20 s, since [StepTerm] is [Continue], the sequence moves
on to the next step, Step 2.
Step 2Since [Time] is 10 s and [Action] of [Offset] is [Keep], the last value of the previous step,
Step 1, in other words +10 V, is held for 10 s.
After the lapse of 10 s, since [StepTerm] is [Continue], the sequence moves on to the next
step, Step 3.
Step 3Since [Time] is 15 s, [Offset] is +5 V, and [Action] of [Offset] is [Const], a constant value, i.e.,+5 V, is held for 15 s. When the sequence moves on from Step 2 to Step 3, the output voltage
abruptly changes from +10 V to +5 V.
After the lapse of 15 s, since [AutoHold] is [On], the sequence enters standby as is.
Next, when Stop is executed, the sequence moves to Step 0.
Since [StepTerm] is set to [End], the sequence moves to Step 0 even if Resume is executed.
Note that if [StepTerm] is set to [Continue], the sequence moves to Step 4 when Resume is
executed.
Step 0Since [Time] is 5 s, [Offset] is 0 V, and [Action] of [Offset] is [Sweep], the output voltage
declines linearly from +5 V to 0 V over 5 s.
Once the output voltage has reached 0 V after 5 s, the sequence goes into standby in thisstate. At this time, if Start is executed, the same sequence is repeated.

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6.2 Basics

6.2

BasicsThe basics that must be known when using sequence oscillation are explained below.

a) Differences between sequence oscillation and normal oscillation
During sequence oscillation, the equipment operates on individual waveform, frequency,
and amplitude settings independent from normal oscillation (continuous, modulated, sweep,
burst). Regarding sequence oscillation and normal oscillation, assume that each operates asa separate oscillator.

b) Step control parameters and intra-step channel parameters
Sequence oscillation has the following two main types of parameters.
• Step control parameters
Sequence oscillation consists of multiple steps linked to each other. The step flow iscontrolled by the step control parameters, which determine the step continuation time
and the next step. For convenience, the step synchronization code setting is also
included in the step control parameters.
• Intra-step channel parameters
This parameter determines the output status within each step. Along with basic
parameters such as waveform, frequency, and amplitude, it determines how theseparameters change within each step.
Step number

Common setting
Step control
parameters

Intra-step channel
parametersc) Intra-step parameter change pattern
There are the following three patterns in intra-step channel parameters with respect tovalue changes in a step, other than the waveform. These are called action settings. In thecase of the waveform parameter, the setting done in that step is always applied, not theaction setting.
• Constant [Const]
The value is fixed to that set in that step.
• Keep [Keep]
The value immediately before that step is entered is kept. In other words, the valuechanges according to the status of the previous step.
Even when the action setting is [Keep], parameter values can be set but they areinvalid during sequence execution.

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6. USING SEQUENCE OSCILLATION• Sweep [Sweep]
The value changes linearly over the step time from the value immediately before thatstep is entered to the value set in that step. In other words, after the lapse of the steptime in that step, the value reaches the set value. The start value changes according to
the status of the previous step.

Action settings

Parameter change when theaction setting of the next
step is Const

Parameter change when theaction setting of the next
step is Keep

Parameter change when theaction setting of the next
step is Sweep

Previous step

Previous step

Previous step

Next step

Next step

Next step
φSetting
value

Keep

Sweep

Const
φSetting
value
Setting value forthe next step

The value changes fromthe final value of theprevious step to the setting
value of the next step.

The final value ofthe previous stepis kept.

d) Phase at step end [StopPhs]
Normally, when the prescribed step time has
elapsed, the sequence moves on to the next step
regardless of the oscillation phase. However, if
transition to the next step following completion of
one cycle of the waveform, for example, is desired,the end phase (stop phase) can be specified.
Note that the phase is valid only for the phase ofchannel 1 in the WF1974. No stop phase can be set
for channel 2.

StopPhs
setting

When the stop phase is specified, following the lapse of the prescribed step time, thesequence moves on to the next step after the specified phase has been reached, with theoutput setting maintained as is (sweep is not performed during this interval). As a result,the actual step time is longer than the specified step time. The sequence moves on to thenext step with a continuous phase regardless of the stop phase setting.
The following figures show examples of a case in which a stop phase is specified and a casein which it is not specified when the amplitude is changed abruptly during steps. Both thephase setting value and the stop phase setting value are 0° in the example when a stop
phase is specified. In either case, the phase is continuous at the transitions of the steps.
When a stop phase is not specified
in the previous step
Previous step

End ofstep time

Next step

When a stop phase is specified
in the previous step
Previous step

Next step

End ofstep time
Waiting for the stop phase

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6.2 Basics

The stop phase specified here is the phase value based on the oscillation reference phase(oscillation phase of DDS). The end phase that appears in the actual output is equal to[phase setting value of that step] + [stop phase setting value]. Normally, if any is set to 0°,
the sequence moves on to the next step following the completion of 1 cycle. At this time, thestep does not end with the final amplitude value of the waveform but with the top (0° position) amplitude value of the waveform.
When the waveform is a square wave, a stop phase can be set but the step is transferred to
the next step without waiting for the stop phase. In addition, a stop phase can be set but it
is invalid when the waveform is a noise or DC.

Check・Stop phase setting is invalid for a square wave, noise, and DC.
・The sequence changes to the next step after 200 ns (equivalent to 0.072° in
1 kHz) have elapsed from the specified stop phase. In channel 2 of theWF1974, the sequence changes to the next step after approximately 3.7 µs
have elapsed since channnel 1 changed.
・Once a step for which stop phase specification is valid has been passed, thestep change in channel 2 of the WF1974 is fixed to approximately 3.7 µs later
than that in channel 1 (it is not released or accumulated until the sequenceends).

e) Phase at step start
If the waveform of the previous step is DC or noise,
oscillation in the next step starts from phase 0°.
Phase 0° here is the phase value based on theoscillation reference phase (oscillation phase of
DDS), as in the case of the phase at step end (stopphase). The start phase that appears in the actual
output is the phase setting value of that step.
Normally, if the phase is set to 0°, oscillation starts
from 0°.

Phase
setting

The following figures show examples when the phase is set to 0° and 90° and the step after
DC is the sine wave.
Phase setting for the next step = 0°Previous step

Fctn=DC

Next step

Fctn=Sine(±FS)
Phase=0deg

Phase setting for the next step = 90°

Previous step

Next step

Fctn=DC

Fctn=Sine(±FS)
Phase=+90deg

Oscillation starts at 0°

Oscillation starts at 90°

Check
Set the previous step to DC to specify a start phase.

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6. USING SEQUENCE OSCILLATIONf) Two types of branches
The control flow can be changed through manipulation from the panel or an external signal.
This is called branching. For example, the sequence may be made to move to a different stepin response to a change in the status of the equipment under test.
There are two types of branches, as follows.
• State branch [StateB]
The operation branches to the specified step through a signal from a multi-I/O
connector (pin 14). ) p. 60
However, the signal from the multi-I/O connector is checked only after the specified steptime of that step has elapsed (the time being held is not included). ) p. 61• Event branch [EventB]
The operation branches immediately to the specified step through soft key
manipulation or the signal from a multi-I/O connector (pin 11). Even if the stop phasehas been set, it is ignored.
For example, it can be used for saving processes when a failure is detected.

State branch
Event branchg) Step 0 prior to start and upon end
The step in the standby state prior to sequence start is called Step 0. Step 0 is also the state
at sequence end. When the mode changes from the normal oscillation mode to the sequenceoscillation mode, the status changes to the Step 0 output status.
Since this is a special step, the items and meanings that can be set to the step control
parameters differ from those of other steps.
Only the following three items can be set for the step control parameters.
• Step time: At the start of a sequence, the sequence changes to the next step (normally,
step 1) without waiting for this time. The step time is valid when parameters are swept
at the sequence end. If sweep is set for the intra-step channel parameters of step No. 0,
sweeping is performed for this time. ) p. 56• Stop phase: When the sequence is started, the phase specified here is waited for and thesequence changes to the next step (normally, step 1). It is invalid for a square wave, noise,
and DC.
• Step synchronization code output: Step synchronization code output of step No. 0.
The intra-step channel parameter action settings consist only of [Const] (constant) and[Sweep] (sweep), and do not include [Keep] (keep). In other words, the same output setting
always applies to the start and end.

h) Usable waveform limitation
The waveforms that can be used for sequence oscillation are limited to sine wave, squarewave (both normal and extended possible as variable duty range), noise, DC, and arbitrary
waveform.
If using a ramp wave or parameter-variable waveform is desired, on the ARB Edit screen,
copy the desired waveform to the arbitrary waveform and save it in advance as an arbitrary
waveform. During sequence oscillation, ramp wave symmetry and the various parameters
for parameter-variable waveform cannot be specified.
If wishing to use a pulse waveform, save the half-sine edge pulse of the parameter-variable
waveform as an arbitrary waveform.

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6.2 Basicsi) Waveform size
The waveforms used in the sequence are not written to the waveform memory each time thestep is executed. Prior to the sequence execution, the waveforms are expanded to the
512 Kword waveform memories (per channel) when compilation is executed. Therefore, ifmany types of waveforms are used, a memory size allocated to each waveform becomes
consequently smaller. Note that DC and a square wave are created during executing steps(regardless of whether the variable duty range is normal or extended) so that they do not
use the waveform memory. In addition, the required memory size is the same when thesame waveform is repeatedly used. The number of types of waveforms that can be used islimited to 128.
Note the following:• When the allocatable memory size becomes small, the characteristics of the waveforms
may be lost in an arbitrary waveform in the control point format and with many abruptchanges.
• When a large waveform is used in an arbitrary waveform in the array format, the memory
size allocated for other waveforms decreases.
The following table shows the memory size that can be allocated for each waveform.
Waveform

Size

Size adjustment

DC

0W

Fixed

Square wave

0W

Fixed

Sine wave

4 KW, 8 KW, 16 KW, 32 KW, 64 KW, 128 KW, 256 KW, 512 KW

Variable

Noise

32 KW

Fixed

Arbitrary waveform 4 KW, 8 KW, 16 KW, 32 KW, 64 KW, 128 KW, 256 KW, 512 KW(control point format)

Variable

Arbitrary waveform(array format)

Fixed

4 KW, 8 KW, 16 KW, 32 KW, 64 KW, 128 KW, 256 KW, 512 KW

If a parameter-variable waveform, square waveform, pulse waveform, or ramp waveform is copied
to an arbitrary waveform, it becomes an arbitrary waveform in control point format.

Noise is always used in 32 Kwords, of which size is fixed. However, it does not repeat thesame pattern during the output.
An arbitrary waveform in the array format is used with the waveform size transferred fromUSB or GPIB, and the size is fixed.
A sine wave and an arbitrary waveform in the control point format are allocated to theremaining area which is the 512 Kwords minus the total amount of the size of the fixedlength waveforms above. The waveform size is adjusted based on the free memory space
and the number of waveforms. Note that all the memory sizes allocated to each variablelength waveform are the same.
The arbitrary waveforms in the control point format are spread out to the memories, notjust decimated but with the characteristics of the waveform retained, as much as possible.
Caution: In the initial setting, waveforms in all steps are sine waves, and [Continue] is set
for the step termination. If a 512 Kword arbitrary waveform in the array format is specified
for an arbitrary step, with the initial setting remaining, an error occurs when compiling due
to the lack of memory space to allocate the sin wave to the waveform memory. When usinga 512 Kword arbitrary waveform in the array format, compose a sequence which does not go
through the steps requiring another waveform memory.

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6. USING SEQUENCE OSCILLATION

j) Channel ganged operation (WF1974 only)
The step control parameters are common to both channels. The sequence moves to the same
steps for both channels. However, the stop phase can be controlled only on the Channel 1side, so that the end phase of Channel 2 does not necessarily match the desired value. Also
note that even once a stop phase is specified, the subsequent step switching time of channel
2 is fixed to approximately 3.7 µs later than that of channel 1.
On the other hand, the intra-step channel parameters can be set independently for eachchannel.

k) Common sequence settings
Select [Setup] andpress the [Enter] key toopen the window forcommon setting.
Window forcommon setting

The following items are common settings within one sequence.
• Start step [Start Step]
The number of the next step to which the sequence is to move to after Step 0 can be
specified. Normally, 1 is set as this number.
• External trigger polarity [Trig]
When using the external trigger input (BNC terminal) as the sequence start trigger,
specify its polarity. In the case of non-use, set this item to [Off].
Only the trigger input terminal on the channel 1 side is valid in the WF1974.
• External control [ExtCtrl]
Enable this item to control sequence start, stop, hold/resume, and branch with thesignals from the multi-I/O connector (set to [Enable]). When not using the multi-I/O
connector, disable this setting (set to [Disable]). ) p. 64• Allocation of pin 14 of multi-I/O connector [Multi I/O pin 14]
Pin 14 of the multi-I/O connector can be allocated either to sequence start (set to[Start]) or state branch (set to [StateBranch]). ) p. 64• Sync output [SyncOut]
Select whether to output waveform sync signal (set to [Sync]) or LSB (set to[StepCode(LSB)]) of the step sync code to the sync/sub-output terminal. For step synccode, ) p. 68.
If LSB of the appropriate step sync code is set to H and output, it can be used as thetrigger source and the simplified check for sequences can be executed by an oscilloscope.
For multi-I/O connectors, ) “3.2.7 Multi-I/O (MULTI I/O)” in the Basics Instruction
Manual.

l) Other limitations• The amplitude range is automatically determined according to the maximum output levelof the overall sequence. Range switching does not occur during sequence execution.
• The external addition function is forcibly set to off.
• The value set in the oscillator screen is applied for the amplitude and DC offset load
impedance conditions.

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6.3 In-Step Processing Flow

6.3

In-Step Processing Flow

The flow of processing within one step is shown below.
Start

Output is done according to the action setting during the specified step time.
If hold manipulation is performed during this time, the sequence is in the standby
state with the current output status remaining as is until Resume is executed.

If the state branch setting is [On], the state branch signal is checked after the
specified step time has elapsed (time being held not included).

If auto hold setting is [On], the sequence is in the standby state withthe step's last status remaining as is until Resume is executed.

If the stop phase setting is [On], the sequence is in the standby
state until the specified stop phase is reached.

If the state branch setting is [On] and the state branch signal
previously checked is active, the specified step is transitionedto.

Go to state branch
destination step

If not going to state branch
destination
If the setting of jump destination is [On], the sequence goes tothe specified step the specified number of times.

Go to jump
destination step

If not going to jump
destination
The sequence transitions to the next step number or step
number 0, depending on the step termination setting.

Go to next number step

Go to Step 0(sequence termination)

The following transitions occur as the result of event branching or termination execution,
regardless of the intra-step flow.

WF1973/WF1974

If the event branch setting is [On], the sequence moves to thespecified step upon event branch manipulation or signal input.

Go to event branch
destination step

If sequence termination is executed, the sequence moves to
Step 0.

Go to Step 0(sequence termination)

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6. USING SEQUENCE OSCILLATION

6.4

Setting and Manipulation Proceduresa) Switching to sequence oscillation mode
In the top
menu, select[Sequence] andthen press the
ENTER key.

1. Press the MENU MENU key to open the top

menu window. In that window, select[Sequence] and then press the ENTER
ENTER key to switch to the sequenceoscillation mode.
2. The dialog box to confirm whether totransit to the sequence oscillation mode isdisplayed. Select [OK] and press the
ENTER
ENTER key to transit to thesequence oscillation mode.
The sequence creating & editing screen isdisplayed, and the output setting becomesthat of Step 0.

b) Creating & editing a sequence
To use an already saved sequence, press the [Recall] soft key and select the sequence to beused.
To create a new sequence, perform the settings one step at a time.
To reuse setting contents, either copy and paste in their entirety the step control parameters
and intra-step channel parameter settings, or copy and paste the intra-step channel
parameters only (using a soft key).
During editing, the contents of the selected step can be output.
On the sequence creating/editing screen, [Edit] is displayed at the upper right on the screen.
The items of the soft keys on the sequence creating screen are as shown below.
Soft key in [Edit] status
1st stage
Cut

Copy

Paste

Insert▼ 1/3

Step parameters (both step control parameter and intra-step channel parameter)
corresponding to the step number currently displayed can be copied and pasted, and thestep itself can be cut and inserted. Even if a step is cut or inserted, the step numbers
referenced at each step (jump destination or branch destination) are not changed.
2nd stage (Text screen or Single and Dual screen of WF1974)
Step –1

Step +1

CH Copy

CH Paste▼ 2/3

Step numbers are increased and decreased by using [Step +1] and [Step –1].
Intra-step channel parameters corresponding to the step number currently displayed canbe copied and pasted by using [CH Copy] and [CH Paste]. In the WF1974, these soft keys
function are on active channel.
2nd stage (Graph screen)
Step

AutoScale

TRC Setup▼ 2/3

The input field corresponding to the step number can be opened by [Step].
Use [AutoScale] to adjust the vertical axis scale of the graph display so that it will not
saturate.

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6.4 Setting and Manipulation Procedures

The setting screen for the display item and the display scale is opened by [TRC Setup].
3rd stage
CompileReset

Recall

Store

▼ 3/3

A sequence can be saved and retrieved by using [Store] and [Recall], respectively.
All sequence settings are initialized by using [Reset].
A sequence becomes executable by using [Compile].

c) Performing sequence execution preparations
Just calling up a sequence or creating/editing it does not by itself make a sequence
executable.
When the [Compile] (compilation) soft key in the [Edit] status is pressed, whether thesetting contents are appropriate is checked, the waveform data allocation and optimum
output range setting are performed, and the sequence becomes executable (Ready state).
As a result of compilation, an error message is displayed if any settings not preferable for
execution are detected. When the compilation has successfully completed and the sequence
becomes executable, [Rdy] is displayed at the upper right on the screen. The items of thesoft keys in this status are as follows.
Soft keys in [Rdy] status
Start

Edit

Sequence execution is started by [Start].
Returns to the creating and editing sequence screen by [Edit].
The created/edited sequence is cleared if the power is cut off, so be sure to save it as needed.
To do so, press the [Store] soft key in the [Edit] status to open the Save Settings window.
Saving can be done either before or after compilation. (Only in the [Edit] status)d) Executing the sequence
Press the [Start] soft key on the [Rdy] screen to start the sequence execution.
When the sequence is started, [Run] is displayed at the upper right on the screen. The
items of the soft keys in this status are as follows.
Soft keys in [Run] status
Stop

Hold

EventBra

ImmedStope) Pausing sequence execution
Press the [Hold] soft key in [Run] status to pause the sequence, going into standby with theoutput status maintained as is. To resume, press the [Resume] soft key in the [Hold] status.
[Hold] is displayed at the upper right on the screen during the sequence hold status. The
items of the soft keys in this status are as follows.
Soft keys in [Hold] status
ResumeStop

EventBra

ImmedStopf) Executing an event branch
Press the [EventBra] soft key in the [Run] or [Hold] status to execute an event branch. If
event branch is set to [On] during the step under execution, the sequence moves to thespecified step.

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6. USING SEQUENCE OSCILLATIONg) Terminating the sequence
Press the [Stop] soft key in the [Run] or [Hold] status to terminate the sequence, causing it
to move to Step 0.
[Rdy] is displayed at the upper right on the screen and the sequence can be restarted at anytime.

h) Forcibly terminating the sequence without waiting for the stop phase or sweep
Press the [ImmedStop] soft key in the [Run] or [Hold] status to immediately terminate thesequence without stop phase wait or sweep execution, switching to the Step 0 settings.

i) Editing the sequence again
Press the [Stop] soft key in the [Run] or [Hold] status to terminate the sequence. When it
has terminated, press the [Edit] soft key in [Rdy] status to allow sequence creation andediting.
To execute the sequence, press the [Compile] soft key in [Edit] status again.

j) Returning to normal oscillation mode
Select other than [Sequence] (such as [Oscillator]) at the top menu and press the ENTER
ENTER key. The dialog box to confirm whether to exit from the sequence oscillation mode isdisplayed. Select [OK] and press the ENTER ENTER key
In the sequence oscillation mode, displaying the other items of the top menu means
switching to the normal oscillation mode.

k) Controlling the start, stop, and pause of the sequence by using an external logic
signal
Set the external control [ExtCtrl] in common settings to [Enable] (be enabled) to manipulate
the sequence by the TTL level logic input to the multi-I/O connector on the rear panel.
) p. 60
It is recommended to disable ([Disable]) [ExtCtrl] when the control by the external signal is
not used, to prevent a malfunction due to an external noise.
For the multi-I/O connectors and their terminal allocation, ) “3.2.7 Multi-I/O (MULTI I/O)”
in the Basics Instruction Manual.
When the external trigger input (BNC terminal) is used, only the sequence start
manipulation can be performed. ) p. 60
The following manipulations are available.
■ Starting sequences
Falling input in [Rdy] status starts the sequence. This is invalid in [Run] or [Hold] status.
■ Stopping sequences
Falling input in [Run] or [Hold] status ends the sequence and switches to Step 0.
■ Holding/resuming sequence
Falling input in the [Run] status pauses the sequence. Rising input in the [Hold] status
resumes the sequence from where it has been paused.
■ Event branch of the sequence
In [Run] or [Hold] status, falling input during the step where event branch is set to [On]generates an event branch. The sequence changes to the specified branch destination step.

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6.4 Setting and Manipulation Procedures■ State branch of the sequence
In [Run] or [Hold] status, a low level input during the step where state branch is set to [On]generates a state branch. The sequence changes to the specified state branch destination
step. For the timing to check the low level, ) p. 61.
Controlling both the sequence start and the state branch via the multi-I/O connector is notpossible () p. 60). When using the multi-I/O connector for the state branch, use theexternal trigger input (BNC terminal) for the sequence start operation.

Check
・Start, stop, and event branch operations via the multi-I/O connector cause adelay of approximately 0.2 ms to 2 ms and fluctuations.
・Start manipulations by the external trigger input cause a delay of approximately
4.5 µs ± a few 10 ns and fluctuations upon the waveform output and a delay of
approximately 6 µs to 7 µs and the fluctuations upon the DC output. This start
manipulation operates quicker than that of the multi-I/O connectors.

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6. USING SEQUENCE OSCILLATION

6.5

Screen Outline■ Text display [Text] (WF1973) or [Single] (WF1974)
The step control parameters of one step and the intra-step channel parameters of 1 channel
are displayed simultaneously.
Step time
Step number

Common settings

Step control
parameters

Intra-stepchannelparameters■ Simultaneous 2-channel display [Dual] (WF1974 only)
The intra-step channel parameters of one step are displayed simultaneously for twochannels. The only step control parameter that is displayed is the step time.
Step time
Step number

Common settings

Intra-step channel
parameters ofeach channel

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6.5 Screen Outline■ Graph display [Graph]
Graph display shows the trends along step progress for four intra-step channel parameters.
However, the trend shown is that progressing onward in numerical sequence from Step 0.
Statuses of sequences executed not in the order due to jump and branch cannot be
displayed.
Which parameters to display for each trace can be changed through trace settings.
Step time
Step number

Trace settings

Common settings

Trend display for
intra-step channel
parameters[PRM] and [SCL] displayed in the trace settings indicate the display item and the height of
the trace frame, respectively. [OFS] indicates the bottom values in the trace frame forfrequency, amplitude, and duty, and the center value in the trace frame for the offset andphase.
In the [TRC Setup] soft key at the second stage, the settings for four traces and the graphcolors can be changed collectively.
The [AutoScale] soft key at the second stage adjusts the vertical-axis scales in the graphdisplay, including unused steps, to avoid saturation.

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67

6. USING SEQUENCE OSCILLATION

6.6

Description of Step Control Parameters

Step time [Time]
Set the step duration.
Auto hold [AutoHold]
Normally set to [Off].
To not go to the next step after the lapse of the specified step time, and enter the standby state
instead, set [On]. This is useful to move the sequence along while checking the status of theequipment under test one step at a time.
Upon Resume execution or reception of the Resume signal, the processing resumes.
Stop phase [StopPhs]
When set to [On], the phase at the end of that step can be specified.
After the lapse of the specified step time, that step ends after the specified phase has beenreached.
Jump destination [JumpTo]
When set to [On], the step to which the sequence is to go to upon completion of the current
step can be specified.
By specifying [JumpCnt] (jump count), it is possible to configure a loop consisting of arepetition of the same steps.
Jump count [JumpCnt]
When set to [On], it is possible to specify the number of jumps to the step specified with
[JumpTo] (jump destination). When set to [Inf], an infinite loop results.
Note that the number of times that the same step is repeated is [jump count + 1].
State branch [StateB]
When set to [On], the state branch signal of the multi-I/O connector (pin 14) is checked, and if
the signal is active, the specified step is jumped to. However, the state branch signal can bechecked only after the specified step time has elapsed (except for the time being held).
) pp. 58, 61
Event branch [EventB]
When set to [On], the soft keys or the event branch signal of the multi-I/O connector (pin 11) ischecked, and if the signal is active, the specified step is jumped to. ) pp. 58, 61
Step termination [StepTerm]
Specifies whether to jump to the next number step ([Continue]), or go to Step 0 and end thesequence ([End]), upon termination of the step.
Step sync code output [StepCode]Sets the 4-bit logic signal that is output to the multi-I/O connector while on that step. The
right-most bit is D0 (LSB).
For the multi-I/O connector, ) “3.2.7 Multi-I/O (MULTI I/O)” in the Basics Instruction Manual.
D0 (LSB) can be output to the sync/sub-output terminal. ) p. 60

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6.7 Tips for Sequence Creation

6.7

Tips for Sequence Creationa) Repeating the same pattern for more than 1000 times
The maximum value for setting the jump count is 999; therefore, up to 1000 times of step
patterns can be repeated. To repeat more than 1000 times, the following methods can be
performed. Here, the cases of the repetition for 3000 times are described.
■ Aligning the same patterns
Execution of steps J to K for 1000 times

Execution of steps K +1 to L for 1000 times

999 jumps

999 jumps

Step J
JumpTo:Off
Continue

Step K
JumpTo:J
JmpCnt:999
Continue

Step K+1
JumpTo:Off
Continue

Step L
JumpTo:K+1
JmpCnt:999
Continue

Same contents as those of steps J to K

Execution of steps L +1 to M for 1000 times
999 jumps
Step L+1
JumpTo:Off
Continue

Step M
JumpTo:L+1
JmpCnt:999
Continue

Same contents as those of steps J to K

Steps with the same contents can be created easily by using the [Copy] and [Paste] soft
keys. Create the steps with the same contents then revise only the required portions.
■ Creating a multiplex loop by inserting steps to connect the step patterns
Two jumps
999 jumps
Step L
JumpTo:Off
Continue

Step M
JumpTo:L
JmpCnt:999
Continue

Connection DC step
Step M+1
Time:0.1ms
JumpTo:L
JmpCnt:2
Continue
Fctn:DC

If any pause periods of DC can be inserted without a problem, insert a 0.1 ms step, whichlasts the minimum time, to configure a multiplex loop. This allows repetition of the internalloop for integral multiple times. Adding such steps which connect the step patterns canconfigure the loop multiplied for any number of times. Note, however, the following.
• At the step immediately after DC, the phase is initialized. ) p. 57• The total step time is extended for the repeated number of the steps which connect thestep patterns.

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6. USING SEQUENCE OSCILLATIONb) Applying unipolar waveform (when changing both amplitude and offset
simultaneously)
When the amplitude range of a waveform is set to ±FS, if both the amplitude and DC offset
are changed between steps, unintended glitches may occur at the transitions of steps. Thisis because amplitude and DC offset cannot be changed completely at the same time.
Normally, the amplitude is changed first and this causes the glitch.
In this case, using a unipolar waveform (set the amplitude range to 0/+FS or –FS/0) may
solve the problem.
The following describes a sequence with a waveform in which the lower voltage is fixed asshown in the figure below. Assume that the output waveform is a sine wave starting from–90°, with the amplitude changing at every cycle. If the step prior to the sine wave is set toDC, the step of the sine wave starts at the specified phase. In addition, to complete a step in
one cycle, set the step time shorter than one cycle and set the stop phase to 0°.
The following shows the waveform and intra-step channel parameters when the amplitude
range of the sine wave is set to Norm ±FS. Amplitude, offset, and phase are all specified tothe constant value (Const). The description of step control parameters is omitted.
When the amplitude range of the sine wave is ±FS

Glitches occurred

+3 V

+2 V

+1 V
Step 0

Step 1

Step 2

Step 3Fctn

DCSine (±FS)

Sine (±FS)

DC

Amptd

－－－

1 Vp-p2 Vp-p－－－

Offset+1 V+1.5 V

+2 V

+1 V

Phase

－－－

–90deg–90deg－－－In this case, both the amplitude and DC offset change at the transitions of steps, resulting
in a glitch occurrence.

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MULTIFUNCTION GENERATOR

6.7 Tips for Sequence Creation

The following describes the waveform and intra-step channel parameters when theamplitude range of the sine wave is set Norm 0/+FS. Amplitude, offset, and phase are all
specified to the constant value (Const). The description of step control parameters isomitted.
When the amplitude range of the sine wave is 0/+FS+3 V
A glitch does not occur.
+2 V

+1 V
Step 0

Step 1

Step 2

Step 3Fctn

DCSine (0/+FS)

Sine (0/+FS)

DC

Amptd

－－－

1 Vpk

2 Vpk

－－－

Offset

+1 V

+1 V

+1 V

+1 V

Phase

－－－

–90deg–90deg－－－In this case, glitches don't occur, because only the amplitude changes at the transitions of
the steps.
In the case shown in the figure below, even if the amplitude range of waveform is ±FS,changing both the amplitude and DC offset between steps does not cause any problems.
This is because the amplitude and DC offset change at the timing of the waveform level 0.

+3 V

+2 V

+1 V
Step 0

Step 1

Step 2

Step 3Fctn

DCSine ( ±FS)

Sine ( ±FS)

DC

Amptd

－－－

1 Vp-p2 Vp-p－－－

Offset

+1 V

+2 V

+3 V

+1 V

Phase

－－－

0deg

0deg

－－－

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7.
7.1

USING USER-DEFINED UNITSDefinition of User-Defined Unit

It is possible, for example, to set the frequency in rpm (number of rotations over 1 minute)instead of setting the frequency in Hz. It is also possible to set the voltage by converting it to amechanical deviation amount or output voltage after power amplifier output, etc., and set thatinstead of the voltage.
By defining such conversion formulas, the defined units can be used just like regular units.
These units are called user-defined units in this equipment.
User-defined units can be used for the following six parameters: Frequency, period, amplitude,
DC offset, phase, and duty.

7.2

Displaying and Setting User-Defined Units

Select the userdefined unit

72

When the input field of the desired
parameter is open, place the cursor over
the right-most unit and change the unit
with theup/down arrow keys or themodify knob. The unit name that isdisplayed can be freely set.
Even if the unit is changed, only thedisplay unit changes, and the actual
output values remain unchanged.

MULTIFUNCTION GENERATOR

7.3 Defining User-Defined Units

7.3

Defining User-Defined Units■ Setting screen
The settings are done on the Utility screen.

On the Utility
screen, select[User Unit] andthen press the
ENTER key

1. Select the [User Unit] field on the Utility
screen and then press the ENTER ENTER
key.

2. The user-defined unit setting window opens. Select the desired setting item and thenpress the ENTER ENTER key to perform that setting. The input field can also be opened bypressing the corresponding soft key.
The user-defined unit
setting window opens.
Setting target
Unit nameCalculation formula
Multiplier of calculation formula
Offset of calculation formula

The following items can be set in this window.
Setting target [Type]Frequency, period, amplitude, DC offset, phase, and duty can be chosen from.
Unit name [Unit]
The unit name can consist of up to 4 characters. Input one character at a time by moving
the cursor over the desired position with theup/down arrow keys or themodifyknob, or perform input with the numeric keypad.
Calculation formula [Form]
Select either [(h+n)*m] or [(log(h)+n)*m)] as the unit conversion calculation formula. “h”
is the original value of the setting target. The values converted with these formulas are
the setting values that appear on the screen when actually using user-defined units.
The unit for h is fixed as described in the following table according to the setting target.
Setting Target

Unit for hFrequency

Hz

Periods

Amplitude

Vp-p if the amplitude range is +FS
Vpk if the amplitude range is 0/+FS, −FS/0(in either case, value for the specified load impedance condition)

DC offset

V
Value for the specified load impedance condition

Phase

deg

Duty

%

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7. USING USER-DEFINED UNITS

log is the common logarithm with base 10. Caution is required when using the log
calculation formula for values that can be negative, such as DC offset and phase. In thecase of a value that is zero before conversion to a user-defined unit, upon conversion to auser-defined unit using log, “−Inf” is displayed. Likewise, in the case of a value that isnegative before conversion to a user-defined unit, upon conversion to a user-defined unit
using log, “Over” is displayed.
Calculation formula multiplier and offset [m], [n]Set multiplier [m] and offset [n] in the selected calculation formula.
Once every parameter has been set, select [OK] in the lower part of the window and thenpress the ENTER ENTER key.

Check
When using a user-defined unit, the setting resolution may be lower dependingon the multiplier and offset setting.

■ Setting the frequency in rpm
As an example, to enable display and setting of the frequency of 1 Hz as 60 rpm, do thefollowing settings and then select [OK].
Type: Freq
Unit: rpm
Form: (h+n)*m
m: 60
n: 0

Next, on the Oscillator screen, open the frequency input field and change the unit from Hz
to rpm.

Change the unit fromHz to rpm

As a result, it is now possible to display and set rpm values.

74

MULTIFUNCTION GENERATOR

8.
8.1

OTHER UTILITY SETTINGS

Selecting Remote Interface [Remote]GPIB address

8.2

The remote control interface can beselected from USB or GPIB.
When USB is selected, USB ID isdisplayed.
When GPIB is selected, the GPIB address
is set in the range of 0 to 30.

Display Settings [Display]
Set backlight on/off and the brightness
when the backlight is on.
Backlight on/off
and brightness
Display tone

This setting switches the display tone
between bright lettering against a dark
background and dark lettering against abright background.
If the display contents are invisible for the
backlight out, press on the [MENU] key fora while to light up the backlight forcibly.

8.3

Modify Knob and Modify Direction Setting [Modify Direction]
Item transition
direction during
clockwiserotation

WF1973/WF1974

Select whether the selected items move
downward or upward as the modify knob
is rotated clockwise (CW) with the choicelist of the oscillation mode or the waveform
displayed.

75

8. OTHER UTILITY SETTINGS

8.4

Operation Sound Setting [Sound]Set whether or not to output a beep upon
key input, modify knob operation or
occurrence of an error.
Operation
sound

8.5

Self Check [Self Check]
Check the internal status. Remove fromthe equipment all cables except the power
cable before checking.
If there is a problem, consult NF
Corporation or the distributor.

8.6

Product Information Display [Information]
Model

This is only a display of this equipment's
information, and not a setting.

Firmware version
Internal parts
versions
Last calibration
date

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MULTIFUNCTION GENERATOR

9.
9.1

TROUBLESHOOTING

Error Messages When Power Is Applied

The equipment performs a self-check when the power is applied, and if an anomaly is detected,
an error message is displayed. In case of failure, contact NF Corporation or your distributor. If
a message indicating the shutdown was executed due to overheating, check that the installation
location is appropriate (check that the ambient temperature is so high as to cause overheating,etc.).
Hardware initialization failed
Internal error. Failure of the device.
OSC-Block error
Internal error. Failure of the device.
RAM error
Internal memory error. Failure of the device.
ROM error
Internal memory error. Failure of the device.
Last shutdown caused by overheat
The previous power-off was caused by internal overheating.
Check the use environment and the state of the device.
Output not turned on due to overload
The startup output setting was on, but output was not turned on because overload of sync/
sub-output was detected.
The output terminal may be connected to an external voltage source. Check the connection.
Resolve the overload state, and turn on the output again.
Output overload detected; Output turned off
Output was turned on once according to the startup output setting, but output was turned
off because overload of waveform output or sync/sub-output was detected.
The output terminal may be connected to an external voltage source. Check for correctconnection. Resolve the overload state, and turn on the output again.

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9. TROUBLESHOOTING

9.2

Error Messages During Execution

Error messages during execution are displayed mainly when the setting exceeds the output
range. For example, when the frequency is attempted to set to 30 MHz while a square wave isbeing output, an error is displayed and the frequency is set to the maximum frequency for thesquare wave.
Error messages are also displayed upon detection of internal overheating and output overload.
This section describes them in the order of error numbers displayed in the dialog window.
12005: Internal overheat detectedInternal overheating.
The ambient temperature may be too high, or the device may fail. It is recommended toturn off the power to this device.
14006: Internal temperature too high; Auto-shutdown will occur
Internal overheating reached the limit, and this device will be automatically turned off.
The ambient temperature may be too high, or the device may fail.
22017: Function changed to Sine by changing Channel Mode
The waveform of the channel changed to a sine wave because the 2-channel ganged mode
was selected when the waveform is Noise or DC.
22018: Mode changed to Continuous by changing Channel Mode
The mode changed to the continuous oscillation mode because the 2-channel ganged mode
was selected in the burst mode.
The burst mode cannot be used in the 2-channel ganged mode.
22019: Modulation Source changed to Internal due to Channel Mode
The modulation source changed to Internal due to the 2-channel ganged mode.
When the 2-channel ganged mode is selected, the modulation source is once set to internal
regardless of the modulation type.
When the channel mode is 2-phase, constant frequency difference, or constant frequency
ratio, the modulation source of FM and FSK is restricted to internal. Since there is norestriction for other types of modulation sources, make the setting again. When the channel
mode is differential, the modulation source is set to internal, regardless of the modulation
type.
22020: External addition turned off by changing Channel Mode
External addition was turned off because differential is selected for the channel mode when
external addition was used.
External addition cannot be used in the differential mode.
22021: SwpMode changed to Single by changing Channel Mode
The sweep mode changed to single-shot sweep because 2-phase, constant frequency
difference, constant frequency ratio, or differential is set for the channel mode when thesweep oscillation mode is gated single-shot.
Gated single-shot sweep cannot be used in the 2-channel ganged mode.
22022: Mode changed to Continuous by changing Function
The mode changed to the continuous oscillation mode because a waveform that does notmatch the current oscillation conditions was selected in the modulation, sweep, or burst
mode.

78

MULTIFUNCTION GENERATOR

9.2 Error Messages During Execution

For example, when the waveform is changed to pulse during FM with a sine wave, the modechanges to continuous oscillation because FM cannot be done with a pulse. To perform
PWM with a pulse, change the mode to the modulation mode, and then change themodulation type to PWM.
22024: Start-locked occurred due to setting conflict
The specified oscillation cannot be started due to an inappropriate operation setting in themodulation, sweep, or burst mode.
The message regarding the inappropriate setting is displayed when the left [?] soft key ispressed.
22025: SyncOut selection changed to Sync by selection of external modulation
The reference phase synchronization [Sync] was assigned to sync/sub-output because ofswitching from internal modulation to external modulation.
Modulation synchronization [ModSync] and the modulation waveform [ModFctn] can beselected as sync/sub-output only for internal modulation.
22028: Edge time changed due to Width
The edge time was reduced because the current edge time (LE, TE) did not allow
achievement of the specified pulse width time.
Pulse width time has a higher priority than edge time.
22029: Edge time changed due to Duty
The edge time was reduced because the current edge time (LE, TE) did not allow
achievement of the specified pulse width duty.
Pulse width duty has a higher priority than edge time.
22030: Edge time and/or Width changed due to Frequency
The edge time and/or pulse width time were changed because the current edge time (LE,TE) and pulse width time did not allow achievement of the specified frequency.
Frequency has a higher priority than edge time and pulse width time.
22031: Edge time and/or Duty changed due to Frequency
The edge time and/or pulse width duty were changed because the current edge time (LE,TE) and pulse width duty did not allow achievement of the specified frequency.
Frequency has a higher priority than edge time and pulse width duty.
22032: Selected ARB is missing; Edit Memory ARB assigned
The specified arbitrary wave does not exist, so the arbitrary wave in the edit memory was
assigned instead.
This phenomenon occurs when the arbitrary wave previously used was deleted while not inuse. Arbitrary waves are identified by number only.
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, so the amplitude may decrease or the pulse may
be lost.
This phenomenon occurs when the pulse width in the high or low side becomes narrower
than about 8.4 ns in a square wave with an extended duty variable range.
22034: Frequency reduced due to Function
The frequency was changed to a lower value according to the waveform.
The frequency upper limit varies according to the waveform.

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9. TROUBLESHOOTING

22035: Duty changed due to Extend-Off
The duty was changed to a value restricted by the frequency because the duty variable
range of the square wave changed to normal.
When the duty variable range is normal, the variable range of the duty changes according to
the frequency.
22036: Duty changed due to Frequency
The duty was changed to a value restricted by the frequency because the duty variable
range of the square wave was normal.
When the duty variable range is normal, the variable range of the duty changes according to
the frequency.
22037: High level changed due to Low level
The High level was changed due to the change of Low level in relation to the output range.
22038: Low level changed due to High level
The Low level was changed due to the change of the High level in relation to the output
range.
22039: Not acceptable due to another CH limitation
The specified setting could not be done due to the restriction of another channel in a 2channel same value setting.
22040: Frequency and/or DeltaFreq changed due to Function
The frequency and/or frequency difference were changed according to the upper limit
frequency for the waveform when the channel mode was a constant frequency difference.
22041: Frequency of CH1 changed due to DeltaFreq
The frequency of CH1 was changed to maintain the frequency difference when the channel
mode was a constant frequency difference.
The frequency difference has a higher priority than the frequency of CH1.
22042: Frequency changed due to Function
The frequency was changed according to the upper limit frequency for the waveform when
the channel mode was a constant frequency ratio.
22043: Frequency of CH1 changed due to Ratio
The frequency of CH1 was changed to maintain the frequency ratio when the channel mode
was a constant frequency ratio.
The frequency ratio has a higher priority than the frequency of CH1.
22044: Output not turned on due to overload
Output was not turned on because overload of sync/sub-output was detected.
The output terminal may be connected to an external voltage source. Check the connection.
Resolve the overload state, and turn on the output again.
22149: Modulation Source of CH2 changed to Internal by changing CH1 or CH2 setting
The modulation source of CH2 was changed to internal, according to a change of CH1 or
CH2 setting although the modulation source of CH2 had been set to CH1 external in FSK or
PSK.
The modulation source of CH2 can be set to CH1 external only when CH1 and CH2 are in
the same modulation type and external is selected for the modulation source of CH1.

80

MULTIFUNCTION GENERATOR

9.2 Error Messages During Execution

22150: Trigger of CH2 changed to Internal by changing CH1 or CH2 setting
Trigger source of CH2 was changed to internal according to a change of CH1 or CH2 setting
although the trigger source of CH2 had been set to CH1 external in sweep or burst.
The trigger source of CH2 can be set to CH1 external only when external is selected for thetrigger source of CH1 under the following conditions.
• CH1 and CH2 are in the same sweep type. CH1 and CH2 are in the same sweep mode
(except for continuous sweep).
• CH1 and CH2 are in the same burst mode (except for auto burst).
23045: Data out of range; Data discarded
The input value was discarded because setting of a value outside the setting range wasattempted.
23129: MOD/ADD IN connector used by external addition now
The external modulation/addition input connector is currently used for external addition. It
cannot be used for external modulation simultaneously.
23130: MOD/ADD IN connector used by external modulation now
The external modulation/addition input connector is currently used for external modulation.
It cannot be used for external addition simultaneously.
23133: Output overload detected; Output turned off
Output was turned off because overload of waveform output or sync/sub-output was
detected.
The output terminal may be connected to an external voltage source. Check for correctconnection. Resolve the overload state, and turn on the output again.
23134: Self Check failed; Auto-shutdown will occur
Self check failed. The power is turned off.
The device may fail.
32004: Not able to delete this ARB; This ARB is in current use
The arbitrary wave currently being output or used cannot be deleted.
In the modulated oscillation mode, the arbitrary wave used as the internal modulation
waveform also cannot be deleted.
35005: File-system error
Internal error. The device has failed.
60001: Sequence under editing not stored; Shutdown?
The sequence being edited has not been saved yet.
Save it, if necessary. It will be erased when the power is turned off.
60002: ARB waveform under editing not stored; Shutdown?
The arbitrary wave being edited has not been saved yet.
Save it, if necessary. It will be erased when the power is turned off.
61056: Data beyond lower limit; Value clipped to lower limit
Setting a value below the lower limit value was attempted, so the lower limit value was set.
61057: Data beyond upper limit; Value clipped to upper limit
Setting a value above the upper limit value was attempted, so the upper limit value was set.

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9. TROUBLESHOOTING

61058: Zero data not allowed
A zero value cannot be set for the parameter.
61059: Invalid operation
Invalid operation. Insertion of a control point was attempted for where it was not allowed
during editing of an arbitrary wave.
61060: Invalid operation
Invalid operation. Deletion of a control point that cannot be deleted was attempted duringediting of an arbitrary wave.

82

MULTIFUNCTION GENERATOR

9.3 Conflict Messages for Modulation

9.3

Conflict Messages for Modulation

These messages are displayed when the [?] soft key is pressed when the specified modulation
cannot be executed, due to inappropriate setting (conflict state). The messages describe theinappropriate setting.
HopFreq beyond upper limit for current Function
The hop frequency exceeds the output range for the current waveform in FSK.
Lower the hop frequency.
MOD/ADD IN connector used by external addition now
The external modulation/addition input connector is currently used for external addition, so
it cannot be used for external modulation.
Turn off external addition.
Modulated peak or bottom value out of range[Carrier Value + Deviation] or [Carrier Value – Deviation] exceeds the output range in FM,
PM, OFSM, or PWM.
Change the carrier value, or lower the deviation.
Modulated peak or bottom phase out of range[Carrier Value + Deviation] exceeds the output range in PSK.
Lower the carrier value or deviation.
Modulation Type not compatible with current Function
The modulation type does not match the current waveform. For example, PWM is specified
for a sine wave.
Change the modulation type.

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9. TROUBLESHOOTING

9.4

Conflict Messages for Sweep

These messages are displayed when the [?] soft key is pressed when the specified sweep cannot
be executed due to inappropriate setting (conflict state).
The messages describe theinappropriate setting.
Frequency beyond upper limit for Gated sweep
The frequency exceeds the upper limit frequency for gated sweep.
Lower the frequency.
Gated sweep not available for DC
Gated sweep is not available for DC waveforms.
Change the sweep mode to continuous or single-shot.
Start value out of range
The start value exceeds the output range.
Change it to a value within the output range.
Stop value out of range
The stop value exceeds the output range.
Change it to a value within the output range.
Sweep Type not compatible with current Function
The sweep type does not match the current waveform. For example, duty sweep is specified
for a sine wave.
Change the sweep type.

84

MULTIFUNCTION GENERATOR

9.5 Conflict Messages for Burst

9.5

Conflict Messages for Burst

These messages are displayed when the [?] soft key is pressed when the specified burst cannot
be executed due to an inappropriate setting (conflict state). The messages describe theinappropriate setting.
BrstMode not compatible with current Function
The mode of burst oscillation does not match the current waveform. For example, when
trigger burst is specified for noise.
Change the mode of burst oscillation.
Frequency beyond upper limit for current Function
The frequency exceeds the upper limit frequency for the current waveform.
Lower the frequency.

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85

9. TROUBLESHOOTING

9.6

Compile Error Messages for Sequence

These messages are displayed when an unexecutable setting is found as a result of sequencecompilation.
Amptd-Offset conflict
CH:N Step:M
Amptd (Step K) - Offset (Step L)
The amplitude and offset do not satisfy mutual restriction in step M of channel N. The
amplitude is set at step K, and the offset is set at step L.
Lower the amplitude or offset.
Fctn-Freq conflict
CH:N Step:L-M
The frequency exceeds the upper limit for the waveform between step L and step M ofchannel N.
Lower the frequency.
Fctn-Freq-Duty conflict
CH:N Step:M
Freq (Step K) - Duty (Step L)
The frequency and duty of the square wave do not satisfy mutual restriction in step M ofchannel N. The frequency is set at step K, and the duty is set at step L.
Lower the frequency, or bring the duty close to 50%.
Selected ARB is missing
CH:N Step:M
The arbitrary wave specified at step M of channel N does not exist.
Specify another arbitrary wave.
Selected ARB loading failed
CH:N Step:M
The arbitrary wave could not be read in step M of channel N.
Internal error. The device failed.
Too complex to check
The sequence was too complex to be checked.
Simplify the sequence structure.
Too many or too large Functions used
The number of waveforms used exceeds 128, or the total exceeds 512 Kwords.
Reduce the number of waveforms, or the number of data points of the arbitrary wave in thearray format. )P.59

86

MULTIFUNCTION GENERATOR

9.7 Suspected Failure

9.7

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

Possible Cause

ActionPower cannot beappliedThe power supply used exceeds the
rated range.

Use a power supply within the rated
range.

“2.3 Grounding andPower Supply
Connection” in the
Basics Instruction
Manual.

A malfunction occurred due toexternal noise, etc.

Set the equipment in a satisfactory
location.

“2.2 Installation” in the
Basics Instruction
Manual.

Panel operation
is not possible

The remote status is set.

Set the local status.

—

The keys or the modify knob aredamaged.

Notify NF Corporation for repair.

—The output levelis abnormal.

The ambient temperature orambient humidity is outside theguaranteed operation range.

Use the equipment in anenvironment within thespecifications.

Sufficient warming up has not been
performed.

Perform warming up for at least 30
minutes after power application.

DC offset is added.

Set DC offset to 0 V.

“4.4.8 Setting DC offset”
in the Basics Instruction
Manual.

User-defined unit is used.

Select a standard unit.

“4.4.7 Setting the amplitude” in the Basics
Instruction Manual.

The load impedance function isused.

Set Hi-Z.

“4.4.12 Setting the load
impedance” in the Basics
Instruction Manual.

A different interface setting has
been selected.

Perform the settings in accordancewith the interface to be used.

p. 75

The GPIB address or USB ID differsfrom the program.

Make the GPIB address or USB ID
match the program.

p. 75

The same GPIB address or USB ID
as that of another unit is used.

Set a GPIB address and USB ID not
the same as those of other units.

p. 75

Setting initialization has not been
executed.

The descriptions in the instruction
manuals assume that the settings
have been initialized.
Therefore, execute setting
initialization.

“4.3.8 Restoring the initial settings” in the
Basics Instruction
Manual.

The channel to be manipulated isthe other channel.

Check whether the channel is CH1
or CH2.

“4.3.6 CH1/CH2 switching key and active channel (WF1974 only)” in
the Basics Instruction
Manual.

The setting of the back light islighting out.

Press the [MENU] key for a while tolight up the backlight forcibly.

“4.2.3 Top menu / a)
Displaying the topmenu” in the Basics
Instruction Manual.

Setting throughremote control is
not possible.

The operationdiffers from that
described in the
instruction
manual.

Display contents
are invisible forthe backlightout.

WF1973/WF1974

Reference“2.2 Installation” in the
Basics Instruction
Manual.
—

87

10.

MAINTENANCE

10.1 Outline■ Operation Contents
The following maintenance actions are required to ensure optimum use of this equipment.
● Operation check:

Checks whether the equipment works properly.

● Performance check:

Checks whether the equipment meets its ratings.

● Adjustments & Calibration: When the equipment does not meet its ratings, have it
adjusted or calibrated by NF Corporation to restore its
performance.
● Fault repair:If this fails to remedy the problem, have NF Corporation
investigate the cause of the problem and repair it.

This instruction manual describes easy-to-perform operation checks and performance tests.
For more advanced checks, adjustments, calibrations, and fault repairs, consult NF
Corporation or a distributor.

WARNING This product contains high-voltage parts. Never remove the cover.
All internal inspections of this product are to be performed only by service
technicians qualified by NF Corporation.

88

MULTIFUNCTION GENERATOR

10.1 Outline■ Equipment Used
Operation checks and performance tests require the following instruments.
Required Performance

Recommended Instrument

DigitalmultimeterAC voltage
TrueRMS
Accuracy: ±0.1%(1 kHz to 100 kHz)DC voltage
Accuracy: ±0.1%

Power meterand power
sensor100 kHz to 30 MHz
R&S NRVS, NRV-Z5
5 µW to 250 mW(−23 dBm to +24 dBm)
Accuracy: 0.02 dB
Resolution: 0.01 dB

Measurement of AC
voltages of 100 kHz andhigherUniversal
counter

Accuracy: 0.1 ppm

Agilent 53131A
Opt 010(High-stability TB)

Frequency, duty, andinter-channel timedifference measurement

Oscilloscope

300 MHz or higher,
2 GS/s, 50 Ω input

Agilent DSO6032A

Leading-edge time andtrailing-edge timemeasurement

Spectrum
analyzer

10 kHz to 1 GHz
Resolution: 100 Hz

Agilent E4411B
Opt 1DR (Narrow RBW)

Harmonic and nonharmonic spurious
measurement

BNC cable

Characteristic impedance:
50 Ω
Length: 1 m

RG-58A/U

BNC(f)Banana
conversion
adapter――

For connecting a BNC
cable to the binding post ofa digital multimeter

BNC(f)-N(m)conversion
adapter

Characteristic impedance:
50 Ω―

For connecting a BNC
cable to a spectrum
analyzer

BNC(f)-N(f)conversion
adapter

Characteristic impedance:
50 Ω―

For connecting a BNC
cable to a power sensor

WF1973/WF1974

Agilent 3458A

Usage Purpose
Measurement of AC
voltages of 100 kHz or
lower, and DC voltage―

8910. MAINTENANCE

10.2 Operation Checks■ Items to verify before operation check
Verify the following items before performing an operation check.
● Is the power supply voltage within the rated range?
● Is the temperature range within the 0 to +40ºC range?
● Is the relative ambient humidity within the 5 to 85%RH range (and the absolute
humidity within the range of 1 to 25 g/m3)?
● Is there no condensation?
■ Function checks● Checks upon power application
Check if there is no error display at power application.
When an error massage is displayed, ) p. 77.
In the case of an abnormal display at power application, switch off the power, and switch
it back on 5 or more seconds later.
● Self-check
Execute [Self Check] on the Utility screen.
) p. 76● Major functions check
To prevent erroneous settings, first perform setting initialization (execute [Reset] on the
Utility screen).
Next, connect FCTN OUT to an oscilloscope using a coaxial cable with characteristic
impedance of 50 Ω, and monitor the output.
In this state, change the following settings a number of times to check whether the unit
functions normally. The items that require a numeric value to be set, such as thefrequency, can be checked more accurately by using both the numeric keypad and themodify knob.
• Waveform ( FCTN FCTN shortcut key)
• Frequency ( FREQ FREQ shortcut key)
• Amplitude ( AMPTD AMPTD shortcut key)
• DC offset ( OFFSET OFFSET shortcut key)
• Output on/off ( OUT )● GPIB and USB checks
Perform some of the setting changes implemented in the major functions check abovefrom the GPIB or USB interface, and verify that the same output changes result.
At this time, check that either [GPIB] or [USB] is displayed in the status display area at
the top of the screen.
Also, with either [GPIB] or [USB] displayed in the status display area, press the [Local]
soft key, and check that the above status display has disappeared and that the local statusis returned to (when the status is other than local lockout).

90

MULTIFUNCTION GENERATOR

10.3 Performance Tests

10.3 Performance Tests■ Performance tests
Performance tests are done as part of preventive maintenance to prevent performancedegradation of the equipment.
Perform performance tests when required, such as for performance checks during
acceptance inspections, periodic inspections, and after repairs.
If the specifications are found to be unmet as the result of a performance test, repair isrequired. In this case, contact either NF Corporation or a distributor.
■ Items to verify before performance test
Verify the following items before performing a performance test.
● Is the power supply voltage within the rated range?
● Is the temperature range within the +20 to +30ºC range?
● Is the relative ambient humidity within the 20 to 70%RH range?
● Is there no condensation?
● Has the unit been warmed up for at least 30 minutes?
■ Preparations before performance test
● The signal cable to be used is a coaxial cable terminated at both ends with BNC
connectors, with characteristic impedance of 50 Ω, thickness of RG-58A/U or greater,
and a length of 1 meter or less.
● In the case of items that specify 50 Ω termination, set the input impedance of theconnected measuring device to 50 Ω.
● For equipment that cannot be set to 50 Ω input, attach a 50 Ω termination to the inputof the measuring device (feedthrough terminator).
● Signals of up to approx. 24 dBm can be measured (when amplitude setting = 20 Vp-p/
open). Use a separate coaxial attenuator if needed to ensure that the allowed input of
the measuring device is not exceeded. Particularly in the case of power meter (power
sensor) and spectrum analyzer, use caution as these types of equipment are easily
damaged.
● The setting for each test item describes the items to be additionally changed after
setting initialization (executing [Reset] on the Utility screen) followed by setting theoutput to [On] (LED lights when OUT is pressed).

10.3.1Frequency accuracy test

FCTN OUT → Universal counter input (50 Ω termination)
Use a coaxial cable.
Setting:
After initialization of the settings, set the frequency to 1 MHz and theamplitude to 10 Vp-p/open.
Measurement: Set the universal counter to the frequency measurement mode and measure
the frequency.
Judgment:
The results are normal if within the following ranges.
However, annual variation of up to +1 ppm/year is possible, so that one year
after shipping, the accuracy may have deteriorated within the range of±4 ppm (999.996 kHz to 1.000004 MHz).

Connection:

Rated range
0.999997 MHz to 1.000003 MHz

WF1973/WF1974

91

10. MAINTENANCE

10.3.2Sine wave amplitude accuracy test

Connection:
Setting:
Measurement:
Judgment:

10.3.3

FCTN OUT → Digital multimeter (AC voltage TrueRMS measurement)
Use a coaxial cable.
After initialization of the settings, set the amplitude as detailed in thetable below (frequency is set to 1 kHz).
Measure the output voltage for each waveform with the RMS value.
The results are normal if within the ranges listed in the table below.

Amplitude Setting (Open Load Value)

Rated Range

20 Vp-p (7.071 Vrms)

7.000 Vrms to 7.142 Vrms

5 Vp-p (1.768 Vrms)

1.749 Vrms to 1.786 Vrms

3 Vp-p (1.061 Vrms)

1.049 Vrms to 1.072 Vrms

1 Vp-p (0.3536 Vrms)

0.3493 Vrms to 0.3578 Vrms

0.3 Vp-p (0.1061 Vrms)

104.3 mVrms to 107.8 mVrms

0.1 Vp-p (35.36 mVrms)

34.29 mVrms to 36.42 mVrms

0.02 Vp-p (7.071 mVrms)

6.293 mVrms to 7.849 mVrms

DC offset accuracy test

■ DC only
Connection:
Setting:

FCTN OUT → Digital multimeter (DC voltage measurement)
After initialization of the settings, set the waveform to DC. The DC offset
settings are as listed in the table below.
Measurement: Measure the output voltage with DC.
Judgment:
The results are normal if within the ranges listed in the table below.
DC Offset Setting (Open Load Value)

Rated Range±10 V±9.895 V to ±10.105 V±3 V±2.965 V to ±3.035 V±1 V±0.9850 V to ±1.0150 V

0V–5.000 mV to +5.000 mV■ AC+DC
Connection:
Setting:

FCTN OUT → Digital multimeter (DC voltage measurement)
After initialization of the settings, set the oscillation mode to burst oscillation, the burst mode to gate, and the trigger to external off (sine wave osillation stops at 0°). The amplitude setting is as detailed in the figure below.
The DC offset setting remains unchanged at 0 V.
Measurement: Measure the output voltage with DC.
Judgment:
The results are normal if within the ranges listed in the table below.

92

Amplitude Setting (Open Load Value)

Rated Range

6.4 Vp-p−37.00 mV to +37.00 mV

3.5 Vp-p−22.50 mV to +22.50 mV

1.3 Vp-p−11.50 mV to +11.50 mV

MULTIFUNCTION GENERATOR

10.3 Performance Tests

10.3.4Sine wave amplitude/frequency characteristics test

■ 100 kHz and lower
Connection:
FCTN OUT → Digital multimeter (AC voltage TrueRMS measurement,
50 Ω termination)
Use a coaxial cable.
Setting:
After initialization of the settings, set the amplitude and frequency as
detailed in the table below.
Measurement: Measure the output voltage for each frequency with the RMS value.
Judgment:
Regarding the various amplitude settings, the results are normal if theerror at each frequency using the measurement value at 1 kHz as thereference is within the ranges listed in the table below.
Amplitude
Setting (Open
Load Value)

Measurement
Value at 1 kHz

Error at 50 kHz

Error at 100 kHz

Error at 100 kHz for
Each Amplitude Named as
Follows

20 Vp-pReference value±0.1 dB±0.1 dB

X1 (dB)

5 Vp-pReference value±0.1 dB±0.1 dB

X2 (dB)

3 Vp-pReference value±0.1 dB±0.1 dB

X3 (dB)

1 Vp-pReference value±0.1 dB±0.1 dB

X4 (dB)

0.3 Vp-pReference value±0.1 dB±0.1 dB

X5 (dB)

0.1 Vp-pReference value±0.1 dB±0.1 dB

X6 (dB)■ 100 kHz and higher
Connection:
FCTN OUT → Power meter (power sensor)
Use a coaxial cable. Signals of up to approx. 24 dBm can be measured. Use a
separate coaxial attenuator to ensure that the allowed input of the power
sensor is not exceeded.
Setting:
After initialization of the settings, set the amplitude and frequency as listed
in the table below.
Measurement: Measure the output voltage or power for each frequency.
Judgment:
Regarding the various amplitude settings, the results are normal if theerror at each frequency using the measurement value at 100 kHz as thereference is within the ranges listed in the table below. The error at 100 kHz
Xn (n = 1 to 6) measured in advance with the digital multimeter is added tothe measurement range.
For example, when X1 = –0.05 dB, the judgment range at 20 Vp-p, 5 MHz is−0.1 dB to 0.2 dB.
Amplitude
Setting (Open
Load Value)

Measurement Valueat 100 kHz

Error at
300 kHz

Error at
1 MHz

20 Vp-pReferencevalue−X1 ±0.15 dB−X1 ±0.15dB−X1 ±0.15 dB −X1 ±0.3 dB −X1 ±0.3 dB −X1 ±0.8 dB

5 Vp-pReferencevalue−X2 ±0.15 dB−X2 ±0.15dB−X2 ±0.15 dB −X2 ±0.3 dB −X2 ±0.3 dB −X2 ±0.5 dB

3 Vp-pReferencevalue−X3 ±0.15 dB−X3 ±0.15dB−X3 ±0.15 dB −X3 ±0.3 dB −X3 ±0.3 dB −X3 ±0.5 dB

1 Vp-pReferencevalue−X4 ±0.15 dB−X4 ±0.15dB−X4 ±0.15 dB −X4 ±0.3 dB −X4 ±0.3 dB −X4 ±0.5 dB

0.3 Vp-pReferencevalue−X5 ±0.15 dB−X5 ±0.15dB−X5 ±0.15 dB −X5 ±0.3 dB −X5 ±0.3 dB −X5 ±0.5 dB

0.1 Vp-pReferencevalue−X6 ±0.15 dB−X6 ±0.15dB−X6 ±0.15 dB −X6 ±0.3 dB −X6 ±0.3 dB −X6 ±0.5 dB

WF1973/WF1974

Error at
5 MHz

Error at
10 MHzError at20 MHzError at
30 MHz9310. MAINTENANCE

10.3.5Sine wave total harmonic distortion test

Connection:

FCTN OUT → Spectrum analyzer
Use a coaxial cable. Signals of up to approx. 24 dBm can be measured. Use a
separate coaxial attenuator to ensure that the allowed input of thespectrum analyzer is not exceeded.
Setting:
After initialization of the settings, set the frequency to 20 kHz. Set theamplitude as listed in the table below.
Measurement: Measure the harmonic spurious up to the 7th order, and obtain the total
harmonic distortion through calculation. Using X2 to X7 (dBc) as therelative values of the harmonic spurious up to the 7th order, using the 20
kHz basic wave as the fundamental harmonic, total harmonic distortion
THD is obtained with the following formula.

THD =

X2
-----10+ 10

X3-----10+ 10

X4-----10+ 10

X5-----10+ 10

X6-----10+ 10

X7-----10

X2 to X7 are the relative levels of 40 kHz, 60 kHz, 80 kHz, 100 kHz, 120
kHz, and 140 kHz, respectively.
Increase the input attenuator of the spectrum analyzer until the relative
level of the harmonic spurious stabilizes.
The results are normal if within the following ranges.

Judgment:

10.3.6

10

Amplitude Setting(Open Load Value)

Total Harmonic Distortion

20 Vp-p0.2% or lower

3 Vp-p

0.2% or lower

1 Vp-p

0.2% or lower

Sine wave harmonic spurious test

Connection:

FCTN OUT → Spectrum analyzer
Use a coaxial cable. Signals of up to approx. 24 dBm can be measured. Use a
separate coaxial attenuator to ensure that the allowed input of thespectrum analyzer is not exceeded.
Setting:
After initialization of the settings, set the amplitude and the frequency aslisted in the table below.
Measurement: Measure the harmonic spurious up to the 5th order.
Increase the input attenuator of the spectrum analyzer until the relative
level of the harmonic spurious stabilizes.
Judgment:
The results are normal if within the following ranges.

94

Amplitude
Setting(Open Load
Value)

Maximum Harmonic
Spurious Level up to
5th Order for
Frequency Setting of
100 kHz

Maximum Harmonic
Spurious Level up to
5th Order for
Frequency Setting of
1 MHz

Maximum Harmonic
Spurious Level up to
5th Order for
Frequency Setting of
10 MHzMaximum Harmonic
Spurious Level up to
5th Order for
Frequency Setting of
30 MHz20 Vp-p−60 dBc or lower−60 dBc or lower−43 dBc or lower−30 dBc or lower

3.5 Vp-p−60 dBc or lower−60 dBc or lower−50 dBc or lower−40 dBc or lower

MULTIFUNCTION GENERATOR

10.3 Performance Tests

10.3.7Sine wave non-harmonic spurious test

Connection:

FCTN OUT → Spectrum analyzer
Use a coaxial cable. Signals of up to approx. 24 dBm can be measured. Use a
separate coaxial attenuator to ensure that the allowed input of thespectrum analyzer is not exceeded.
Setting:
After initialization of the settings, set the amplitude and frequency as listed
in the table below.
Measurement: Measure the maximum value of the non-harmonic spurious.
Judgment:
The results are normal if within the following ranges.

10.3.8

Amplitude
Setting(Open Load
Value)

Maximum NonHarmonic Spurious
Level for Frequency
Setting of 100 kHz

Maximum NonHarmonic Spurious
Level for Frequency
Setting of 1 MHz

Maximum NonHarmonic Spurious
Level for Frequency
Setting of 10 MHz

Maximum NonHarmonic Spurious
Level for Frequency
Setting of 30 MHz

20 Vp-p−60 dBc or lower−60 dBc or lower−50 dBc or lower−45 dBc or lower

3.5 Vp-p−60 dBc or lower−60 dBc or lower−50 dBc or lower−45 dBc or lower

1 Vp-p−60 dBc or lower−60 dBc or lower−50 dBc or lower−45 dBc or lower

Square wave duty accuracy test

FCTN OUT → Universal counter (50 Ω termination)
Use a coaxial cable.
Setting:
After initialization of the settings, set the waveform to square wave and theamplitude to 20 Vp-p/open. The variable duty range, frequency, and duty
settings are as listed in the table below.
Measurement: Set the universal counter to the duty measurement mode. Set the trigger
level of the universal counter to 0 V. Since the measured values are subject
to fluctuation due to jitter (particularly when the variable duty range is
extended), perform averaging.
Judgment:
The results are normal if within the following ranges.
Connection:■ Normal variable duty ranges
Frequency
100 kHz

Duty
0.9% to 1.1% when 1% is set

49.9% to 50.1% when 50% is set

98.9% to 99.1% when 99% is set

1 MHz

4% to 6% when 5% is set

49% to 51% when 50% is set

94% to 96% when 95% is set

3 MHz

37% to 43% when 40% is set

47% to 53% when 50% is set

57% to 63% when 60% is set■ Extended variable duty ranges
Frequency
100 kHz

Duty
0.9% to 1.1% when 1% is set

49.9% to 50.1% when 50% is set

98.9% to 99.1% when 99% is set

1 MHz

4% to 6% when 5% is set

49% to 51% when 50% is set

94% to 96% when 95% is set

3 MHz

37% to 43% when 40% is set

47% to 53% when 50% is set

57% to 63% when 60% is set

WF1973/WF1974

95

10. MAINTENANCE

10.3.9Square wave rising/falling time test

FCTN OUT → Oscilloscope (50 Ω termination)
Use a coaxial cable.
Setting:
After initialization of the settings, set the waveform to square wave and theamplitude to 20 Vp-p/open. The variable duty ranges are as listed in thetable below.
Measurement: Monitor the waveform and measure the rising and falling times.
Judgment:
The results are normal if within the following ranges.
Connection:

10.3.10

Variable Duty Range

Rising Time, Falling Time

Normal

17 ns or less

Extended

17 ns or lessTime difference between channels for 2-phase (WF1974 only)

CH1 FCTN OUT → Universal counter, input 1 (50 Ω termination)
CH2 FCTN OUT → Universal counter, input 2 (50 Ω termination)
Use coaxial cables of the same type and length.
Setting:
After initialization of the settings, set the channel mode to 2PHASE, theamplitude to 20 Vp-p/open, the CH2 phase to 180°, and the frequency to 10
MHz. The waveform settings are as detailed in the table below.
Measurement: Set the universal counter to the time interval mode between input 1 andinput 2, and measure the time difference between CH1 and CH2. Set thetrigger level of the universal counter to 0 V for both inputs 1 and 2, and set
the trigger polarity to rising for both inputs. Since the measurement values
are subject to fluctuations, average them.
Judgment:
The results are normal if within the following ranges.
Connection:

96

Waveform

Rated Range

Sine wave

30 ns to 70 ns

Square wave (normal variable duty range)

30 ns to 70 ns

Square wave (extended variable duty range)

30 ns to 70 ns

MULTIFUNCTION GENERATOR

Index2-channel device use ...................................34
2Phase ....................................................392-phase ...................................................39
2Tone ......................................................41
Both ........................................................37
constant frequency difference ...............41
constant frequency ratio ........................43
copying parameters ................................35
copying settings .....................................35
Diff ..........................................................45
differential output ..................................45
phase difference changing .....................39
phase synchronization ...........................38
Ratio .......................................................43same frequency ......................................39
synchronization ......................................38
two-tone ..................................................41
unifying settings of 2 channels .............37
42 Vpk ......................................................... IVburst ....................................................... 85
conflict ....................................... 83, 84, 85
during execution .................................... 78
modulation ............................................. 83
power-on ................................................ 77
sequence ................................................. 86
sweep ..................................................... 84
external frequency reference using ........... 50
connection and usage procedures ......... 50
enabling the external frequency
reference ............................................. 51
status display ........................................ 52

G
GPIB ............................................................ 75

M

Application ..................................................... I
arbitrary waveforms creating .....................28
array format ...........................................28
control point format ...............................28
creating a new waveform .......................30
creating/editing screen ..........................29
data formats ...........................................28
edit memory ...........................................28
examples .................................................31
memory capacity required for saving ...32
outputting created waveform ................32
saving created waveform .......................32
saving location .......................................28
selecting the arbitrary waveform to
be output .............................................29

maintenance ................................................ 88
amplitude accuracy test ........................ 92
amplitude/frequency
characteristics test ............................. 93
DC offset accuracy test ......................... 92
duty accuracy test ................................. 95
equipment used ..................................... 89
frequency accuracy test ......................... 91
harmonic spurious test ......................... 94
measuring equipment ........................... 89
non-harmonic spurious test .................. 95
performance tests .................................. 91
rising/falling time test .......................... 96
time difference between channels for
2-phase ................................................ 96
total harmonic distortion test ............... 94
modify direction setting (modify knob) ...... 75
modify knob and modify direction
setting .......................................................... 75

B

P

A

Basics ............................................................. ID
display settings ............................................75E
error messages .............................................77

WF1973/WF1974

parameter-variable waveforms details ........ 1
2nd Ord LPF Step ................................. 21
Angle Ctrl Sine ........................................ 6
Bottom Referenced Ramp ..................... 27
CF controlled sine ................................... 5
CF Ctrl Sine ............................................ 5
Chattering-Off Sine ............................... 12

97

Chattering-On Sine ...............................11classification .............................................1
Clipped Sine .............................................4
conduction angle controlled sine .............6
Damped Oscillation ...............................22
Exponential Fall ....................................20
Exponential Rise ....................................19
Gaussian Pulse ......................................13
Half-Sine Edge Pulse .............................26
Half-Sine Pulse ......................................16
Haversine ...............................................15
Lorentz Pulse .........................................14
Multi-Cycle Sine ......................................8
Off-Ph Ctrl Sine .....................................10
off-phase controlled sine ........................10
On-Ph Ctrl Sine .......................................9
on-phase controlled sine ..........................9
Oscillation Surge ....................................23
other waveform group ............................25
pulse group .............................................13
Pulse Surge ............................................24
second-order LPF step response ...........21
Sin(x)/x ...................................................18
Staircase Sine ..........................................7
steady sine group .....................................3
surge group .............................................23transient response group .......................19transient sine group .................................9
Trapezoid Pulse ......................................17
Trapezoid with Offset ............................25
Unbalanced Sine ......................................3
product information display .......................76R
remote control ................................................ I
remote interface selecting ...........................75

S
safety precautions ...................................... III
safety-related symbols ............................... IV
self check ......................................................76
sequence oscillation .....................................53
action settings ........................................55
allocation of multi-I/O connector ...........60
amplitude range .....................................60
auto hold .......................................... 61, 68
branches .................................................58
change pattern .......................................55
channel ganged operation .....................60
channel parameters ...............................55

98

common settings .................................... 60compile ................................................... 63
constant (action setting) ....................... 55
control parameters ................................ 68
control parameters and channel
parameters ......................................... 55
creating & editing ................................. 62
differences from normal oscillation ...... 55
editing again .......................................... 64
event branch ............................. 58, 61, 68
event branch executing ...................61, 63
example .................................................. 53
executing ................................................ 63
execution preparations ......................... 63
external addition function .................... 60
external control setting ...................60, 64
external trigger setting ......................... 60
forcibly terminating .............................. 64
glitch ...................................................... 70
hold ........................................................ 63
jump .................................................61, 68
keep (action setting) .............................. 55
load impedance setting ......................... 60
multiplex loop ........................................ 69
parameter change pattern in step ........ 55
pausing .................................................. 63
phase at start ........................................ 57
phase at step end ............................56, 68
phase at step start ................................ 57
processing flow in step .......................... 61
returning to normal oscillation mode ... 64
screen outline ........................................ 66
setting and manipulation procedures .. 62
start step setting ................................... 60
state branch .............................. 58, 61, 68
step 0 ...................................................... 58
step control parameters ........................ 68
step sync code ..................................60, 68
step termination ..............................61, 68
step time ..........................................61, 68
stop phase ........................................56, 68
sweep (action setting) ........................... 56
switching to sequence mode ................. 62
sync code ..........................................60, 68
sync output setting ................................ 60
terminating ............................................ 64
trace setting ........................................... 67
unipolar waveform application ............. 70
waveform limitation .............................. 58
waveform size ........................................ 59

MULTIFUNCTION GENERATOR

sound setting ...............................................76
suspected failure .........................................87
synchronizing multiple units ......................46
connection procedure .............................46
status display .........................................48
synchronization ......................................48

T
troubleshooting ............................................77

U
USB ..............................................................75
user-defined units using .............................72
defining ...................................................73
displaying and setting user-definedunits .....................................................72W
waste disposal ............................................. IV

WF1973/WF1974

99

If there are any misplaced or missing pages, we will replace the manual. Contact the sales representative.

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 thismanual.
・ We assume no responsibility for influences resulting from the operations in thismanual.

WF1973/WF1974 Instruction Manual (Application)
NF CORPORATION
3-20 Tsunashima Higashi 6-chome, Kohoku-ku, Yokohama-shi 223-8508, JAPAN
Phone: 81-45-545-8128 Fax: 81-45-545-8187
http://www.nfcorp.co.jp/© Copyright 2007, NF Corporation

http://www.nfcorp.co.jp/

NF Corporation
6-3-20, Tsunashima-higashi, Kohoku-ku, Yokohama 223-8508 JAPAN