[BC] Harris SX-1 Spur Problem

[James Boyd]

I have a Harris SX-1 in my care that has a spur problem.  Modulated spurs at
plus and minus 50 kHz from the carrier at about 45 dB down from carrier.
The usual suspects have been checked.  PDM frequency is on at 60 kHz.  PDM
waveform is fine.  Output of oscillator is spectrally ok.  All mosfets in
PDM and PA are ok.  All power supply voltages are in spec.  Have looked at
power supplies with scope to see if any regulators are oscillating.  Nothing
found.  All of the big caps have been replaced.  Anyone have any ideas of
the cause of such a problem?
 
James Boyd
Boyd Broadcast Technical Services
Tualatin, OR