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Model 20 speaker rebuild
#2

Hi and welcome to the Phourm!
Don't know if I've ever seen the inductance measurement listed for a field coil. It should be but the norm is resistance. The resistance is important as it will determine the voltage drop a cross the coil. This can be critical if the field coil is in the negative leg of the power supply because it will determine the amount of bias voltage the power supply will develop. The model 20 it's in the positive leg.
Noting the size of the filters I'd take a guess and say between 5 and 10 Henries. Don't think it is really critical.
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
Model 20 speaker rebuild - by mjmont1 - 06-27-2011, 09:22 PM
Re: Model 20 speaker rebuild - by 7estatdef - 06-28-2011, 04:10 PM
Re: Model 20 speaker rebuild - by tdbisel - 07-06-2011, 09:47 PM



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