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Thanks for the reply Kevin-
-------Subject repeaters will have to remain
unnamed as I currently enjoy a good relationship with their point of origin and
I want very much to keep the situation that way. I will say however that
transmitter circuit wise , they are esentially the same as those produced by
Spectrum and I have a couple of them too. I other words, a simple crystal
oscillator (with an audio modulated varicap modulating the crystal capacitance)
followed by a multiplyer string and final amplifier-----ie, no PLL's. The
difference in the modulation (FM) noise of of the subject repeaters and
others is noticable via a monitoring receiver-----some repeaters are
quieter than others and I'm not talking about RF quieting----I'm talking about
differences in audible background hiss assuming a "full quieting" strong RF
signal. Do you have any ideas as to where the "hiss" modulation might
be coming from. I think it is random phase noise in the crystal oscillator
but I can't point at the problem part or design problem and am wondering if the
crystal it's self could be my noise source.
Scott
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