[Heathkit] Heathkit Digest, Vol 104, Issue 11

[G3OOU at aol.com]

In a message dated 15/09/2012 16:06:16 GMT Standard Time,  
heathkit-request at mailman.qth.net writes:

That  SURE sounds like a heterodyne oscillator coil peaked wrong on 20M!!! 
I'm  often wrong, but years ago I built two of those for friends, and found 
 
that when peaking the coils, sometimes there was a "sweet spot" that  
wasn't 
the real peak and it was troublesome like that.  Any "shock"  to the 
oscillator would let it run a while.  Hope this  helps!!



This issue sounds like a spurious response in the crystal with enough  
activity to allow it to oscillate. I have noticed these spurs in several Heath  
band oscillator crystals when measuring their internal parameters, usually  
50-200KHz on the high side, but never enough to oscillate on the wrong  
frequency.
 
73

Bob

Bob F Burns
C Eng,  FIET, MSE
Amateur Radio Callsign: G3OOU
Registered RSGB  Instructor
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