Measurement System Troubleshooting - Agilent Technologies E8362B Service Manual

Troubleshooting

Measurement System Troubleshooting

Measurement System Troubleshooting
This section provides troubleshooting procedures for the measurement portion of the PNA
series network analyzer. In this section, the analyzer is used as a tool to help isolate the
suspected faulty functional group. Once the faulty functional group is determined,
troubleshooting steps are provided to help you isolate the faulty assembly or part.
This section is divided into two major sections for troubleshooting. The first section mainly
covers the standard S-parameter measurement troubleshooting
page 4-50). However, some parts are applicable for the frequency offset section. The second
section is for troubleshooting the frequency offset section, option 080 (refer to
thru pages 4-56). The
section will also reference portions of the S-parameter troubleshooting section in its
troubleshooting process as well as the troubleshooting of the E836xB, option 081 (external
reference switch option).
Before you begin—consider: Where do you see a problem?
If you are seeing a problem at
troubleshooting procedure, starting with:
S-Parameter Mode).
If you are experiencing problems in frequency offset mode only, perform the
Test" on page 4-33 and then perform the
080)" on page 4-52.
You should also consider the problem indications which are observed and whether the
observed condition is a soft failure or a hard failure. With a soft failure, the network
analyzer's performance has degraded to an unacceptable level, yet it continues to operate
and displays no error messages. For this type of failure, performance tests must be
conducted to isolate the problem. Begin with viewing the error terms as described in
Appendix A. This will help isolate most problems. If additional tests are required, refer to
"Performance Tests (Agilent N2721A Software Package)" on page
With a hard failure, the PNA does not perform well and displays one or more error
messages. To diagnose and repair a hard failure: Refer to "error messages" below and
perform the procedures in those sections that are applicable for your particular error
message.
Error Messages
PHASE LOCK LOST: The level of the signal from at least one of the reference receivers, and
sensed by the A11 phase lock board, is too low to be accurately captured. this could be due
to a problem in the source group, signal separation group, or receiver group (refer to
"Checking the Source Group" on page
page 4-46, and "Checking the Receiver Group" on page
SOURCE UNLEVELED: The source ALC circuits on the A12 source or the A16 test set
motherboard—E8363B and E8364B only—is running open-loop. For the E8362B, replacing
the A12 source can correct this. For the E8363B or E8364B, check the cable connections for
W37 and W38 from the A23 and A24 detectors to the A16 test set motherboard, and for
W39 from A16 to the A21 SOMA 50. If the problem is associated with one port and not the
other, replace the detector associated with the problem port. If the problem affects both
ports, replace the A16 test set motherboard.
4-28
"Checking the Frequency Offset Group (Option 080)" on page 4-52
, perform the standard S-parameter test set
[Preset]
Verifying the A, B, R1, and R2 Traces (Standard
"Checking the Frequency Offset Group (Option
4-33,
PNA Series Microwave Network Analyzers
"Checking the Signal Separation Group" on
4-50).
E8362B, E8363B, E8364B
(pages 4-29 thru
pages 4-52
"Serial Bus
3-30.
Service Guide E8364-90026