[R-390] More On Low Audio Problem

[Frederick Bray]

First, let me thank everyone who has replied -- both on and off list.

I think I have narrowed the problem down to the first AF amp/cathode 
follower.  I would appreciate it if those who are more experienced that 
I with the 390A can confirm that I am on the right track.

I used an audio signal generator to ascertain that a signal injected at 
the local and line level controls seems to produce a normal audio output.

Using a VTVM, I confirmed that on there is an AC voltage on terminal 1 
of the wide/sharp switch and that I can trace this voltage through the 
switch.  Jumpering this voltage to terminal 6 on the switch seems to 
restore the audio level to approximately normal, or at least much closer 
to normal.

 From looking at the schematic, I think that what I am doing is 
bypassing the first AF/cathode follower and going directly to the local 
and line AF amps.

Does this make sense?

Thanks,

Fred Bray
KE6CD