[dtvmcdonald]

Thanks very much Peter, that's what I need to know. This implies that the
audio amp system, after the diode detector, is bad. I will try investigating the
output stage. As I said, I can reach it with a scope probe without removing
the chassis, and probably can reach it with a special soldering "gun" tip.

It would help, of course, if I were still the size I was at 10 years old and just as limber.