One last question I hope about this. I pulled the IC301. Is there a way to
check any of the 7 pins for shorts with an ohm meter? I tried a few of them
& didn't find any shorts. It is very hard to read the IC, but it looks like
it is a TA8427K (NTE7158).

Is D431 an FR104? I have a lot of diodes. Is this a special diode or is
there a common replacement?

Thanks, Jim (When one lives in the woods of Maine one has to rely on the
internet for answers.)