Rohde & Schwarz 1164.4391.03, Service Manual

Page: 196 / 254

Troubleshooting R&S FSP
1164.4556.82 3.92 E-1
Troubleshooting – MW Converter
The most frequent error occurring on MW converters is that the signal level displayed on the spectrum
analyzer >3 GHz is too low or missing.
•
Level conditions on the MW converter
Action Error and error cause
Apply a high-frequency signal (f >3 GHz) at the
MW converter input with a level of -20 dBm and
measure the converted level at the output
connector.
If the instrument is operated on an adapter the
LO (connector X102 standard frontend) should
be taken out to the MW converter (connector
X167).
R&S FSP7:
- Input connector diplexer X169
- Output connector X161
R&S FSP13/30:
- Input connector YIG filter X169
- Output connector X161
R&S FSP40:
- Input connector diplexer X168
- Output connector X163
Output level at 404.4 MHz: > -20 dBm If the level is missing or too low, a module is
defective on the MW converter. Check levels of
the modules on the MW converter unit. (see the
following items)
If the measured level is within tolerances, the
attenuator (or the diplexer with R&S FSP13/30)
or a subsequent module in the signal path is
defective.
•
Level conditions on the diplexer
Action Error and error cause
Apply a high-frequency signal (f >3 GHz) at the
diplexer input with a level of –20 dBm and
measure at the output connector.
R&S FSP7:
- Input connector diplexer X169
- Output connector diplexer X8
R&S FSP13/30:
- Input connector X231
- Output connector X233
- Note: The diplexer is not installed on the
MW converter unit (see chapter 5 item 150).
R&S FSP40:
- Input connector diplexer X168
- Output connector diplexer X5
Output level >-27 dBm
If the level is missing or too low, replace the
diplexer. (Refer to "Replacing Diplexer".)
If the measured level is within tolerances, one of
the subsequent modules on the MW converter is
defective.