Agilent Technologies HP 8719D Service Manual page 258

Figure 9-1. Typical Return Loss Trace of a Good Cable
Verify Shorts and Opens
Substitute a known good short and open of the same connector type and sex as
the short and open in question. If the devices are not from one of the standard
calibration kits, refer to the
for information on how to use the .~~~~~~~~~~~..~~~ function. Set aside the
short and open that are causing the problem.
1. Perform an S11 l-port calibration using the good short and open. Then press
turn the front panel knob to enter enough electrical delay so that the trace
appears as a dot at the left side of the circle. (See Figure 9-2a, left.)
Replace the good short with the questionable short at port 1. The trace of
the questionable short should appear very similar to the known good short.
Connect the good open to port 1. Press @Z&XGQ ~~~~~~'~~~~ and
turn the front panel knob to enter enough electrical delay so that the trace
appears as a dot at the right side of the circle. (See Figure 9-2b, right.)
Replace the good open with the questionable open at port 1. The trace of the
questionable open should appear very similar to the known good open.
Accessories Troubleshooting 9-5