Technical data

85108L System Manual
System Service and Troubleshooting
Troubleshooting Strategy
6-6
3. Use error messages and internal diagnostics
The network analyzer has built-in self-tests that run automatically at power up. They can locate
many problems in the system. If there is a failure of any of the self-tests, a message appears on the
display.
During normal operation, the network analyzer continually monitors its operation. When a failure
or abnormal operation is detected, a “running error” message is sent to the display.
The following procedure takes advantage of the network analyzer’s built-in self-tests and
monitoring to help locate a failure.
This procedure assumes that the proper instrument states and hardware states have been loaded
from the configuration disk into the network analyzer. If not, refer to Appendix C, “Loading the
System Configuration Disk,” for instructions to load the proper machine dump configuration file.
1. Start with the line power OFF to all instruments.
2. Switch the line power ON to the instruments in the following order:
— Microwave amplifier (if used)
— Sources
— Test set
— 85102
— 85101
3. As you turn on each instrument, watch the front-panel indicators for performance as shown in
Table 6-2. If an instrument does not power up properly, refer to the service manual for that
instrument for troubleshooting information.
4. If the 85101 does not complete the power on sequence, refer to “Network Analyzer Startup
Problems” on page 6-10.
5. If a “running error” message appears on the network analyzer display after the power on
sequence is completed, not the error and then press the
ENTRY OFF key. If the error message
repeats, refer to “Running Error Messages Specific to Pulsed-RF Systems” on page 6-8.