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Re: S-band

This is easier to detect in SSB mode rather than FM.  If your regulator 
is flipping out you should here the conversion noise drop considerably, 
as if you were turning the power on an off.  Often wiggling or pushing 
on the regulator will show a bad connection--often a poor solder 
connection to ground, and one that can be easily fixed.

A sputtering LO will also have the same symptoms.  If the crystal has 
aged to a point where it no longer is oscillating properly, there is 
often a variable capacitor in the oscillator circuit that can be tweaked 
to provide reliable starting.  Of course, this will also affect the LO 
frequency quite a bit, so it's nice to have a known signal source of a 
frequency counter so that you know where things are when you are done.

-Andy K0SM/2

> Could something (maybe a voltage regulator on your preamp) be heating 
> up, going into thermal shutdown, cooling off and heating up again and 
> again?
> -Joe KM1P

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