Rohde & Schwarz FSP3 Service Manual page 188

Troubleshooting
Checking the 4-fold D/A Converter on the Detector Board.
Normal action
Detector Board Pretune-DAC Test
The 4-fold D/A-converter on the detector board is
checked.
One D/A converter controls the frequency-
dependant IF gain on the IF filter for frequency
response correction. The other ones are provided
for options (microwave
generator).
The first output voltage of the 4-fold D/A converter
is measured, thus checking the basic function of
the control interface (in DCON gate array), also.
Channel Nominal voltage
8 666 mV
1164.4556.82
converter, tracking
FATAL ERROR!
Detector: Pretune DAC FAIL - check DCON and pretune DAC
Selftest aborted.
3.84
Error and error cause
Replace the detector board
R&S FSP
E-1