AN-105
OP930D Functionality
Over view
The OP930D is a dual channel insertion and return loss tester. The OP930D is similar to the OP930 except anadditional source port and detector is added to streamline testing of duplex cables and to allow for simplified
testing of cables with unlike connectors. The test system has two source ports and two power meters. While Port Aand Port B are treated as two separate channels, they share the same source modules and are regulated by a 1x2switch, activating on one channel at a time. The corresponding power meters are configured to expect readings
from their respective source ports when that source is switched on.
NE W

Functionality
Singlemode Schematic
1310nm

WDM Coupler

1 x 2 switch
to Port ANE W

to Port B

1550nmMultimode Schematic
850nm
Laser

WDM Coupler

1300nmLaser

2 x 1 switch

1 x 2 switch
to Port A

850nm
LEDto Port B

WDM Coupler

1300nmLEDFigure 1: Singlemode and multimode schematics for inside of an OP930

The OP930D has one 1310nm and one 1550nm laser (850/1300 for multimode) that are both fed into a 1x2 switch.
This switch sends the selected wavelength into either Port A or Port B; not simultaneously. This switching is seenin the front panel by the switching LEDs. When Port A is “on,” the corresponding detector expects a measurement.
At this time, Port B is “off” and Detector B is frozen and does not look for any measurements. The same procedure
occurs when Port B is switched active.

1

SANTEC CORPORATION
OptoTestCorp.

5823 Calle
Ohkusa-Nenjozaka,
Komaki,
4750
Quetzal
Aichi 485-0802,
Japan
Camarillo,
CA 93012Doc:
AN-105 Rev. B 12 /13 /13+81-568-79-3536

www.santec.comSANTEC USA CORPORATION
8 05.987.170 0USA Toll Free
+1-800-726-8321
sales@ optotest.com
engineering @ optotest.com
SANTEC EUROPE LIMITED
Tel. +44-20-3176-1550

AN-105

OP930D Functionality

Insertion Loss Reference
For duplex measurements using the OP930D, connect two reference cables to the corresponding source channel,
and then connect the reference connectors to their corresponding OPM channel.
NE W
Detector

Source1310nm

IL-1.72 dBm-2.42 dBm

NE W

0.00 dB
0.00 dB

APC

RefdBm

PCAPC

PC1310 nm
1550 nm

OP930D

Dual IL /RL Test Set

SAVer**APC

HPR*

SAVer**HPR*
APC

Figure 2: A reference setup for duplex cable measurement

Return Loss Reference
Cables terminated with a PC polished connector exhibit the inherent 4% reflection (~14dB). This is the ideal
situation for taking the reference. A clean connector interface on both ends, the APC connection at the front panelof the instrument, and the PC interface of the reference cable are all necessary.
Reference return loss by leaving the PC endface of an APC-PC launch cable unmated. Navigate to the RL screen for
the first channel by pressing the right arrow button twice from the OPM screen. With the launch cable connectedto theN E W front panel, press and hold Ref to begin a return loss reference. Repeat this process for the second set. For
methods of testing APC-APC reference cables, please consult AN-114 RL Testing for APC Cables.

Detector

Source1310
nm77.3 F

RL
POS
CH01

3.3m

14.00

dB

Ref

APC

dBm

APC
1310 nm
1550 nm

OP930D

Dual IL /RL Test Set

SAVer**APCHPR*SAVer**HPR*APCPCPCminimal length is 3 meters

Figure 3: A duplex return loss reference setup*HPR High Per formance Cable** SAVer Cable

2SANTEC CORPORATION
OptoTest
Corp.

5823 Calle
Ohkusa-Nenjozaka,
Komaki,
4750
Quetzal
Aichi 485-0802,
Japan
Camarillo,
CA 93012
Doc: AN-105 Rev.B 12 /13 /13+81-568-79-3536

www.santec.com

SANTEC USA CORPORATION
8 05.987.170 0sales@ optotest.com
USA Toll Free
+1-800-726-8321
engineering @ optotest.com
SANTEC EUROPE LIMITED
Tel. +44-20-3176-1550

AN-105

OP930D Functionality

Testing
Connect the cable(s) to be measured to the reference end of the reference cable and the other end of the cable(s)under test into the optical port of the power meter.
NE WDetectorSource

1310nmILNE W-1.72 dBm
-2.42 dBm

-0.10 dB
-0.18 dB

RefdBm

APCPC

APCPC
1310 nm
1550 nm

OP930D

Dual IL /RL Test Set

DUT***
SAVer**APC

HPR*

SAVer**

DUT***HPR*
APC

Figure 4: Testing the insertion loss and return loss of a duplex cable

Once a proper reference has been taken the instrument will continuously update the return loss value or insertion lossvalue depending on what mode it is in. The OPM and IL screens will show the optical power reading and insertion loss
values, respectively, for both channels simultaneously. Each channel has its own return loss mode so that the distanceand the value can be displayed simultaneously.

1310nmIL-1.72 dBm
-2.42 dBm

-0.10 dB
-0.18 dB

RefdBmFigure 5: Front panel display for duplex cable*HPR High Per formance Cable** SAVer Cable***DUT Device Under Test

3

SANTEC CORPORATION
OptoTestCorp.

5823 Calle
Ohkusa-Nenjozaka,
Komaki,
4750
Quetzal
Aichi 485-0802,
Japan
Camarillo,
CA 93012
Doc: AN-105 Rev.B 12 /13 /13+81-568-79-3536

www.santec.com

SANTEC USA CORPORATION
8 05.987.170 0sales@ optotest.com
USA Toll Free
+1-800-726-8321
engineering @ optotest.com
SANTEC EUROPE LIMITED
Tel. +44-20-3176-1550