Keysight Technologies U3045AM04, User'S And Service Manual

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Keysight U3045AM04 User’s and Service Guide 63
U3045AM04
Service Information
RF Switching Failures
Typical failures may be the loss of RF switch control failure or a non RF failure
as outlined in the prior section. The internal RF switches used in this
instrument are controlled by the +24 Vdc from the Switch Driver board.
1. Confirm that the analyzer and test set are properly connected using the
test set I/O cable (N4011-21002). See Figure 11 on page 17 .
2. Using Multiport Mode (Option 551), verify that the analyzer’s firmware is
correct, and that the test set file is loaded into the analyzer. Refer to
“Network Analyzer Requirements” on page 4 .
3. Using the I/O command values, confirm that the correct address and data
values are used. Refer to “Address and Data Values” on page 38 .
4. Follow the “Non-RF Failures” on page 60 procedure (if not already done
so).
5. Front Panel R and S indicator LED Check.
a. Confirm that the test set Controller Board Status LED’s are On. Refer
to Figure 44 on page 61 . If the LEDs are Off remove the Switch
Driver board, if the LEDs remain Off replace the Controller board.
b. If the Status LEDs are On and the front panel Active LED is On,
suspect the front panel LED board or the ribbon cable (replace as
needed).