Keysight Technologies FieldFox N9913A Service Manual page 51

Troubleshooting
Measurement Group Troubleshooting
Since the input attenuator is set to 10 dB, there should be 6 dB of conversion
loss from the RF input connector to the I.F. Out connector.
The 1 GHz test signal was set to 0 dBm. The input attenuator on the analyzer was set to 10 dB. If
the A4 R.F. Board had 0 dB of conversion loss, the 33.75 MHz I.F. output would measure -10
dBm, but it measured -16 dBm because the A4, R.F. Board has 6 dB of conversion loss.
If the input attenuator is changed from 10 dB to 0 dB, the signal will change by
10 dB to -6 dBm. You can verify the input attenuator performance referencing
the table below.
Input Attenuator Setting (dB)
If the 33.75 MHz I.F. Output level is not correct or the input attenuator
performance is out of tolerance, the most likely cause is the A4, R.F. Board.
Keysight FieldFox Handheld Analyzers Service Guide
33.75 MHz I.F. Output Level (dBm)
0
5
10
15
20
25
30
6
11
16
21
26
31
36
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