Keysight Technologies N5224/5A Service Manual page 109

Troubleshooting
Measurement System Troubleshooting
Equipment Setup
1. Before starting these checks, zero and calibrate the power meter. (See the
power meter user's guide for instructions on setting the calibration factor.)
2. If the Receiver Display
screen, perform the following: Press UTILITY
Utilities
3. Set the sweep speed for a 10 second sweep: Press STIMULUS
then
box.
To isolate a broadband RF signal generation failure, check the test port
output power:
1. Note the power reading displayed on the power meter; it should be the
preset power level +/- 1 dB.
2. Connect the power sensor, in turn, to Ports 2, 3, and 4 and set trace to
measure S22, S33, and S44 respectively. Note the power reading
displayed on the power meter.
— If the power level is low or high on all test ports, the problem is LO signal
related. Continue with
— If the power level is low or high on only one of the test ports, the problem is
either source group or in the signal separation group. Continue with
"Checking the A14 50 MHz Reference Outputs"
Checking the A14 50 MHz Reference Outputs
1. Refer to the block diagram at the end of this chapter and to
Assemblies and Cables, All Options" on page
W75, W76, and W77, at the A14 frequency reference board.
2. Disconnect cables W75, W76, and W77, one at a time, from the A14
board.
3. Connect the spectrum analyzer to the open connector on the A14 board.
4. The spectrum analyzer should measure a signal at 50 MHz.
5. If any of the 50 MHz signals are not present, replace the A14 frequency
reference board. Refer to
on page
6. If the 50 MHz signals are present, reconnect the cables, and then:
Keysight N5224A/25A Service Guide
(Figure 4-7
Receiver Display
, then
Sweep Time
. Set the time to 10.000 seconds in the Sweep Time
"Checking the A14 50 MHz Reference
"Removing and Replacing the A4–A17 Boards"
7-15.
or Figure 4-8) is not on the analyzer
, then
System
.
to check the source group.
6-16. Locate flexible cables
Service
, then
Sweep ,
Outputs".
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