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Model 50A rebuild
#27

Hi Matt,

Lets have a look over in the p/s and see what cooking over there. Measure the dc voltage from the chassis to the bottom of #32. Should see about -16v. Measure the top of #33. Should see about 250vdc+. This is the HV rail and if you follow it thru the circuit more than likely you can find the failure. Common plate voltage would be 200-250vdc except for the 80 and the 24 det tube. Screen grid voltage 75-100vdc but it's going to vary w/the volume control.

Common fails are rf coil pri/no plate on 24A plate, leaky/shorted caps in the HV rail, and out of spec resistor.

Happy hunting!

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
Model 50A rebuild - by Mtmattking - 04-08-2024, 07:19 PM
RE: Model 50A rebuild - by GarySP - 04-08-2024, 08:43 PM
RE: Model 50A rebuild - by morzh - 04-08-2024, 09:30 PM
RE: Model 50A rebuild - by Mtmattking - 04-08-2024, 09:35 PM
RE: Model 50A rebuild - by Mtmattking - 04-08-2024, 09:37 PM
RE: Model 50A rebuild - by klondike98 - 04-08-2024, 09:51 PM
RE: Model 50A rebuild - by Mtmattking - 04-08-2024, 09:57 PM
RE: Model 50A rebuild - by klondike98 - 04-09-2024, 03:20 AM
RE: Model 50A rebuild - by Mtmattking - 04-09-2024, 10:56 PM
RE: Model 50A rebuild - by morzh - 04-11-2024, 08:01 AM
RE: Model 50A rebuild - by Mtmattking - 06-29-2024, 09:58 PM
RE: Model 50A rebuild - by morzh - 06-30-2024, 11:07 AM
RE: Model 50A rebuild - by Mtmattking - 06-30-2024, 12:41 PM
RE: Model 50A rebuild - by morzh - 06-30-2024, 01:16 PM
RE: Model 50A rebuild - by GarySP - 06-30-2024, 04:25 PM
RE: Model 50A rebuild - by Mtmattking - 07-06-2024, 08:26 PM
RE: Model 50A rebuild - by morzh - 07-06-2024, 10:20 PM
RE: Model 50A rebuild - by Mtmattking - 07-07-2024, 01:00 AM
RE: Model 50A rebuild - by RodB - 07-07-2024, 09:24 AM
RE: Model 50A rebuild - by Chas - 07-07-2024, 09:50 AM
RE: Model 50A rebuild - by Paul Philco322 - 07-07-2024, 01:19 PM
RE: Model 50A rebuild - by GarySP - 07-07-2024, 03:19 PM
RE: Model 50A rebuild - by morzh - 07-07-2024, 07:33 PM
RE: Model 50A rebuild - by Mtmattking - 07-15-2024, 01:02 PM
RE: Model 50A rebuild - by Mtmattking - 07-20-2024, 10:28 PM
RE: Model 50A rebuild - by Radioroslyn - 07-22-2024, 09:29 AM
RE: Model 50A rebuild - by Mtmattking - 07-22-2024, 07:10 PM
RE: Model 50A rebuild - by Radioroslyn - 07-23-2024, 07:58 AM
RE: Model 50 Capacitor values - by Mtmattking - 04-08-2024, 10:39 PM



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