The PHILCO Phorum

I think that there may be some conductive crap in one of the trimmers, a mixture of dirt, rust, and mouse pee pee. Believe it or not I usually wash chassis when they get very dirty, TSP is very good and getting rid of dirt and oxidation in things. The problems you are having with this 42-761EZ are precisely the sort of problems I would expect to find in that rusty 38-690 that was on fleabay, except that one had evidence of some very pitted aluminum parts as well as rust.
Regards
Arran

I think you're absolutely right, Arran.

Let's consider which components are band specific - and that would be only the trimmers for each of the five "spread bands" (31M, 25M, 19M, 16M, 13M). So whatever is causing 31M to not operate properly - and causing 25M to not work at all - must be limited to components for those individual bands, and that leaves the trimmers for those bands.

The permeability tuning for those five bands use the same coils; different trimmers are switched in by the band switch in parallel with these coils to make it work on the different bands.

It's beginning to look like I am going to have to remove the RF assembly, which appears to be removable - but does not look to be an easy task.

D Grimes speaking from the grave!!!
Terry

Sounds like you have the culprits in sight...and remember Ron, no good deed goes unpunished.

Murphy

Oy vey!

"Mr. Crusher, please take us out of orbit...one quarter impulse"