Agilent Technologies 8163A User Manual page 159

Return Loss Measurement
Agilent 8163A/B, 8164A/B, and 8166A/B User's Guide, Fourth Edition
5 Move to [RLref] and make sure that the displayed value is correct.
Set [RLref] to the value of the return loss of the reference reflection
you are using. For example, if you are using the Agilent 81000BR
reference reflector, set [RLref] to 0.18 dB.
Figure 92 Measuring the Reflection Reference
6 Switch on the Laser.
7 Press [Menu]. Move to <Reflectance calibration> and press Enter.
The instrument measures the power reflected by the back reflector.
The [RL] value changes to the same value as entered for [RLref].
Tip An alternative step 7 is to select the Return Loss module's [Detail]
screen, then press [RefCal]
Return Loss Measurement
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