[Milsurplus] Somewhat deaf BC-312

[W7QHO at aol.com]

Hmmm...   Just ran into something like this in a BC-342.   Turned out to be 
the diode section in the 
6R7 that performs the second detector function. First time I ever ran into a 
diode section in any of the old tubes of this type (6SQ7, 6Q7, etc.) dim 
enough to do that unless there was a hard failure like a short or open heater. Try 
a fresh 6R7 and see what happens. 

Dennis D. W7QHO
Glendale, CA

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Original message (in part):

Initially it received both AM and CW with good sensitivity, although the 
audio was rather low (using a good pair of high-Z headphones). It was pulling in 
10MHz WWV
 fine on a few feet of 'antenna'.
  
 Over the past couple of days the audio level has faded more, and I can no 
longer
 hear AM signals. With the BFO on, I can hear CW signals, and can tune AM
 signals by zero-beating the carrier. But AM seems to have gone.
  



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