Hello All----
Here is a "crystal" question for the group. Do
crystals vary in the amount of random phase noise produced in or by a typical
crystal oscillator / FM modulator circuit as used in a typical repeater
transmitter? Now, more to the issue. I have a series of repeaters that have more
transmitted background audio hiss than the average of other repeaters
on the band. I have, in testing, dissabled all of the audio modulating circuitry
up to the varicap diode without any change in transmitted noise . This leaves
only the crystal and it's oscillator circuit as the culprit noise
source-------hence my question. Do crystals vary in produced FM (phase) noise.
If the answer is yes, Which crystal manufactures make quiet crystals and just
how does one insure that he gets this need across to a crystal
supplier?
Scott, N6NXI
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