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42-PT94 Transitone
#1

I picked up a nice example of this set at the WARCI swap meet in Milwaukee last month. Cheaply. Which, in hindsight, should've sent up a red flag. And nice, in that the cabinet was completely restored and looks very nice. When I took out the chassis, I see the previous owner had completely recapped the set. Well so far so good. That's when I discovered that the leads to the speaker cone were torn out, which was clue #1 this wasn't the bargain it was cracked up to be. OK, so $52 later for a speaker recone, and a new volume control from Mark, and I'm left with a set that has a buzz to it and can only get a garbled version of the strong local station on the dial. The tubes all test good, and I even tried a different stronger external antenna to no avail. I'm ordering a schematic set from Chuck tonight to try to trace out the "repairs" the previous owner did to see if 1.) the capacitors are even in the correct places and 2.) he has the polarity correct on them.

That said, can anyone point me in the right direction on what to check next or what could be causing the buzz (which the volume control does silence) and the garbled-ness of the station that does come in? The variable capacitor doesn't seem to be grounding out, as movement of it doesn't affect reception. However when I touch the side of the chassis, I lose the station. May have to double check the wiring too... he may have missed some of that fossilized rubber coated wire that crumbles to the touch.

Rule of thumb, and lesson learned; if it looks too good to be true, or seems like too much of a bargain, it probably is! I have a feeling I inherited someone else's headache with this baby.

Greg V.
West Bend, WI
Member WARCI.org
#2

If you have a buzz there may be anything from a hanging wire on an amp input to a wrongly installed electrolytic cap and so on.

I would not trust the recapping done by someone else I do not know, unless it was a person whom I do know and whose expertise I trust.

Start from the caps' check, then voltages etc.
#3

Agree with Morzh. It maybe something as simple as a loose connection for the loop antenna or a bad tube with leaky filament to grid short. Keep us posted
Terry
#4

Will do. Once I get the schematics from Chuck I'll dig into it deeper. I know there is some of that nasty old crusty "rubber" wire that wasn't replaced that I have to get to yet. Some was replaced, but not all. That right there may be a problem in itself.

Greg V.
West Bend, WI
Member WARCI.org




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