4-38 Keysight N5224A/25A Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
5.
. If the observed problem was frequency
banded rather than broadband related, set the analyzer frequency to the
center of the problem band. The spectrum analyzer should measure a
signal above the network analyzer setting. For analyzers with DSP version
4.0, the signal is 7.61 MHz above the network analyzer setting. For
analyzers with DSP version 5.0, the signal is 7.44 MHz above the network
analyzer setting.
6.
If the signal is not present but the 50 MHz reference signal from
the A14 50 MHz Reference Outputs”
is present, replace the faulty
“Removing and Replacing the A4–A17 Boards”
7.
If the signal is present, reconnect cables W1 and W2, and then continue
with
“Checking the A5 and A10 Source Outputs”
.
Checking the A5 and A10 Source Outputs
1.
Refer to the block diagram at the end of this chapter and to
Assemblies and Cables, All Options” on page 6-16
. Locate the cables W3
and W4 at the A5 source 1 board or cables W7 and W8 at the A10 source 2
board. (W7, W8, and A10 are only available in 4-port models and 2-port
models with Option 224.)
2.
Disconnect cables W3 and W4 or cables W7 and W8, dependent on which
source board is to be checked, at the A7, A8, A12, or A13 50 GHz Doubler
board.
3.
Connect the spectrum analyzer to the open connector at the end of the
cable that connects to the source board to be checked.
4.
Set the network analyzer for an 800 MHz CW frequency and observe the
spectrum analyzer measurement. An 800 MHz signal should be present.
5.
. If the observed problem was frequency
banded rather than broadband related, set the analyzer frequency to the
center of the problem band. The spectrum analyzer should measure a
signal above the network analyzer setting. For analyzers with DSP version
4.0, the signal is 7.61 MHz above the network analyzer setting. For
analyzers with DSP version 5.0, the signal is 7.44 MHz above the network
analyzer setting.
6.
If the signal is not present but the signals from
are present, replace the appropriate source
“Removing and Replacing the A4–A17 Boards” on
.
7.
If the signal is present, reconnect all cables, and then continue with
“Checking the A7, A8, A12, and A13 50 GHz Doubler Outputs”
.