Greetings Friends of the Filament,
I have a problem on my SX110 that I have been trying to trace down for a
while. When the BFO is turned on, the set goes quiet unless I turn off the AVC.
I know the directions say to do this, but...in the 60's when I had a new SX110,
it didn't behave this way. Also since it is the same basic circuit as the S 40,
etc. and they don't behave this way, I am trying to trace out the problem.
Pin 2 (plate) to the 6SC7BFO tube reads 217v instead of 235v. R28 that
feeds it is about 10% too high. But my problem is too much injection
overwhelming the AVC circuit. Changing R28 would increase the
injection...wouldn't it? When I touch Pin 3 (grid) with a digital meter, the
signals return as if it is bleeding off some of the injection.
Is my problem with the BFO circuit or the AVC? Could someone else who has a
SX110 let me know if theirs behaves this way? All help is appreciated. 73 Mike
KF6KXG