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Another aqusition a Model 20
#12

Well I was over at my radio buddies house and along with a Atwater Kent Keil table (model 55 chassis) he gave me a 171 tube. Fixed the smoldering BC resistor problem. Converted the power supply a choke input. Dropped the voltage down a bit but plays fine. Funny thing is it as less 60cy hum than without the input capacitor.
The only thing that's got me stumped on this set is the plate voltage on the 24A detector tube. Diagram sez 30v. I've got like 130v. All the series resistors check ok and replaced the cathode resistor (was open). Did put in a 5meg resistor in the plate circuit to lower the voltage. Plays better with about 60 to 80v. Don't know if it matters much just bugs me that doesn't match up with the diagram.
Still need to recone the speaker and give the chassis a good cleaning.
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
Another aqusition a Model 20 - by 7estatdef - 02-26-2011, 07:00 PM
Re: Another aqusition - by TA Forbes - 02-27-2011, 01:00 AM
Re: Another aqusition - by 7estatdef - 02-27-2011, 09:31 AM
Re: Another aqusition - by TA Forbes - 02-27-2011, 02:07 PM
Re: Another aqusition - by 7estatdef - 02-27-2011, 03:26 PM
Re: Another aqusition - by 7estatdef - 02-28-2011, 09:15 PM
Re: Another aqusition - by 7estatdef - 02-28-2011, 10:22 PM
Re: Another aqusition - by 7estatdef - 03-01-2011, 09:22 AM
Re: Another aqusition - by 7estatdef - 03-01-2011, 11:01 PM
Re: Another aqusition a Model 20 - by 7estatdef - 03-02-2011, 11:06 PM
Re: Another aqusition a Model 20 - by Ron Ramirez - 03-03-2011, 08:48 AM
Re: Another aqusition a Model 20 - by 7estatdef - 03-17-2011, 05:51 PM
Re: Another aqusition a Model 20 - by codefox1 - 03-18-2011, 10:36 AM
Re: Another aqusition a Model 20 - by 7estatdef - 03-18-2011, 05:44 PM
Re: Another aqusition a Model 20 - by 7estatdef - 03-18-2011, 07:04 PM



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