> Are the cables coming from the GPS reference are the same
> length at both sites?
Maybe I'm missing something here, but how the heck would the length of the
cable from the reference oscillator to the transmitter/exciter matter? It's
just the frequency reference (10 MHz or whatever) for the synthesizer; it
has no effect on delay, phase, amplitude response, or anything else related
to the modulated audio.
> Also if these are VHF it could be that the reference frequency
> (channel spacing) is 5 kHz, if that is the case a harmonic of a paging
> tone might get past the audio pass band filtering 300 - 3000 Hz
> typically and is fooling the PLL divider.
This seems like a longshot. I think Bill's original guess is most likely on
the right track - a DC offset problem. I'm assuming the transmitters are
being modulated through a non-DC-coupled input to the modulator? Maybe look
for a coupling cap with high leakage. Another thought is asymmetrical
clipping of the audio.
--- Jeff WN3A
