User`s guide
Performance Tests Performance Tests
58 Agilent 81618A/9A and Agilent 81623B/4B/6B/8B Optical Heads, Fourth Edition
Return Loss Test
This performance test applies to Agilent 81623B/4B/6B/Optical Heads.
1 Make sure that all connectors are clean.
2 Connect the equipment as shown in Figure 11 .
3 Press [Preset] on the mainframe.
Figure 11 Return Loss Reference Setup
4
Zero the Return Loss Module and the Optical Head
5 Enable the internal laser source of the Return Loss Module and allow 20 
minutes for it to stabilize.
To ensure traceability, use the 81610CC Reference Cable for calibration 
measurements. Do not use the 81610CC Reference Cable for 
measurements on a Device Under Test. Instead, use a measurement 
patchcord.
It is important to maintain the quality of the straight connector end 
of the 81610CC Reference Cable. Never add another connector to 
the straight end of the 81610CC Reference Cable, since a physical 
connection is made. When the straight end of the 81610CC 
Reference Cable is connected to the 81634B Power Sensor module, 
no physical connection is made so there should be no degradation 
of connector quality.
NOTE
CAUTION










