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#3

Thanks TA! That's very helpful, although I suppose my plans of originality aren't going to entirely work out. Oh well.

I've gone over all the coils carefully now. Power and chokes are good, as well as all the RFs. The field seems to sometimes be opened and sometimes closed, I think there's a bad connection on the lug, but that could end up being another big problem.

There are four bad windings... The secondary of the first af transformer part 22 is bad, as are the primary and one secondary of the phase inverter part 25 and one primary of the output part 36. The latter two open windings are on the same phase of the push-pull amp. I wonder if it's possible that a the grid wire of that 45 somehow fell and hit the plate. That would short B+ to ground through those two transformers and open them.

Using the methods on that page, I can (I think) eliminate parts 22 and 25, then I'll just need a new PP output. How is the part 24 coil dealt with in making those modifications?


Schematic: http://philcoradio.com/tech/images/87.jpg


Messages In This Thread
87 - by skyscraper - 03-30-2014, 06:15 PM
RE: 87 - by TA Forbes - 03-30-2014, 11:39 PM
RE: 87 - by skyscraper - 03-31-2014, 01:44 PM
RE: 87 - by morzh - 04-17-2014, 08:14 PM
RE: 87 - by skyscraper - 04-17-2014, 10:42 PM
RE: 87 - by morzh - 04-18-2014, 11:14 AM
RE: 87 - by Radioroslyn - 04-26-2014, 04:38 PM
RE: 87 - by TA Forbes - 04-27-2014, 09:03 AM



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