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Old 04-11-2022, 10:57 AM
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Yamamaya42 Yamamaya42 is offline
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Join Date: Nov 2018
Location: Round Rock TX
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Correction, The transformer needed is Hammond 290CX not 290AX :O
They are pretty much the same, except for that the CX has 2 more amps on the 6.3v heater winding than the the AX, and when I added all the tubes up, it was too much of a load for the AX having only 2.25A, the CX has 4.5.

Took apart both candohm resistors, the 2nd one is mostly intact, (still bad) and seems to be about 3k, or used to be, which is very close to what is in the FADA Radio schematic (3.3k) at that point.
So, making a guess of 3-3.3k 10w chassis mount resistor for here?

Candohm 1 is completely destroyed, burned and blackened, wire on it broken in many places, looks like it was arcing.

For this, I will just have to see what works, 50/70/100 @ 10w.

There is always some give and take in tube stuff, so it should not be hard to get this going if no info on it can be found.

It's pretty clear what happened to it, capacitor failure, plus lack of fuse protection, this coupled with the fact who ever was using it was not paying attention to it and let it burn up.

Evident by the cathode capacitor for the 6V6GT has exploded, and it's paired resister is burned out.
This caused bias to raise above normal and stress already weak electrolytic capacitor,which shorted, overloading the Candohm which shorted and took out the transformer, had the makers put a fuse in there, this chain would have been broken.

Oh well.

Mouser is about to ship the parts for the TV chassis.
So I can get a start on that, at least.
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