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Back to the model 21
#4

Was able to spend a little more time on it and check over a couple more things. Dropped in the tubes and hung a volt meter across the HV line. Plugged it and gave the off/on switch a twist. Was measuring the HV at the high end of the BC resistor. Seems like the p/s was only making about 150v. Was thinking it must have some leaky bypass caps that are loading the HV line down till I measured the HV at the plate of the output tube (45). I had about 275v there. It seem that the field coil is of sufficient resistance with the load of all the other tube and bad caps that there is 120v drop across it.
Anyway the set is working but need to replace the paper caps and check the resistors so I can get it's maximum performance.
Back to the bench
and to the Orphononic RCA
Terry

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
Back to the model 21 - by 7estatdef - 06-06-2011, 08:53 PM
Re: Back to the model 21 - by 7estatdef - 06-08-2011, 03:59 PM
Re: Back to the model 21 - by Ron Ramirez - 06-08-2011, 07:32 PM
Re: Back to the model 21 - by 7estatdef - 06-08-2011, 09:00 PM



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