Troubleshooting - Agilent Technologies N4413A User Manual

Troubleshooting

Use the following table to help troubleshoot your multiport test system.
Troubleshooting the Test System
Symptom
One or more biases not
applied.
Control computer can not
communicate with the test
set.
The test set does not come
on the first time you use it.
Excessive ripple in data.
High loss on one path with
poor raw data match (as
seen during analyzer sweep)
or inability to make a good
calibration.
Chapter 6
Cause
Bias fuse blown.
Accidental change to GPIB
switch settings.
Line fuse not installed, or
incorrect line fuse installed.
Load termination damaged
by excessive RF power.
Loose connections between
VNA and test set and/or
between test set and DUT.
Poor test cable repeatability.
See "How to Check Test
Cable Repeatability" on
page 75.
Possible signal channel
damage. See "How to Check
Test Cable Repeatability" on
page 75.
Maintenance and Troubleshooting
Troubleshooting
Cure
Check bias fuses. Replace if
needed with fuse of the
same type and rating.
Set the GPIB address as
needed. Restart the system.
See "To Set the GPIB
Addresses" on page
Install the line fuse. Refer to
"How to Set Up the
Multiport Test System
Hardware" on page 18.
Contact Agilent
Technologies. See
"Contacting Agilent" on
page 160 for more
information.
Check and torque the
connectors.
Replace test cables as
needed. You can replace a
single cable, without
replacing the entire set.
Contact Agilent
Technologies. See
"Contacting Agilent" on
page 160 for more
information.
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