Fluke 6080A Service Manual page 215

25. Set the UUT to 800 MHz, 300-kHz dev, 1-kHz mod rate, EXT ACFM on. Connect
the 8840A to TP12 and check that the 8840A reads 0V DC ± 200 mVdc.
Set the UUT to 200-kHz dev. Check that the 8840A reads 0V DC ± 200 mV DC.
26. Set the UUT to 800 MHz, 10-kHz dev, 1-kHz mod rate, EXT ACFM. Place a
600-ohm load on the UUT EXT FM input. Connect 1953A Counter to UUT
output and set the 1953A to read 800 MHz with 1 Hz resolution.
Set the UUT to EXT DCFM. The front panel DCFM indicator should come on
within one second. The 1953A should read within 350 Hz of the 800 MHz ACFM
frequency. Connect the 8840A to TP12. TP12 should read 0V DC. Connect the
8840A to J1-P3. The 8840A should read between 3V DC and 8V DC.
Set the UUT to ACFM. Repeat step 25 to verify performance.
Set the UUT to ACFM.
27. Set the UUT to 300-kHz dev. Set the UUT to EXT DCFM. The front panel
DCFM indicator should come on within one second. The 1953A should read
within 500 Hz of the 800 MHz ACFM frequency. Connect the 8840A to TP12.
TP12 should read 0V DC. Connect the 8840A to J1-P3. The 8840A should read
between 3V DC and 8V DC.
Set the UUT to ACFM. Repeat step 26 to verify performance.
TROUBLESHOOTING AND REPAIR
FREQUENCY AND PHASE MODULATION
6E-17/6E-18