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53-658 selenium rectifier replacement questions
#1

Hi guys -

Picked up a clean 53-658 a few weeks and started on it yesterday.  It's all original and clean under the chassis. 
http://www.nostalgiaair.org/Resources/do...013774.pdf

It does not power up on AC and does not register any volts on my amp meter.  Tubes test good.  Am I correct that the likely culprit is the selenium rectifier?  I haven't replaced one of these yet and could use some guidance.

This article suggest installing a terminal strip with 1N4004 diode and resistor between 20 and 200 ohms.  Outside of starting with a 100 ohm resistor and repeatedly measuring, is there a known resistor value I should use?
http://www.w3hwj.com/index_files/RBSelenium2.pdf



Thanks,
Paul
#2

Measure the AC voltage from the anode of the selenium to the - side of the filter caps (B-) should see 120vac or so. If not check the off on switch. If that checks out then measure the DC voltage from the cathode of the selenium to B-. Should see abt 100vdc. If not then the selenium is bad.

Gezz that an awful schematic.

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
#3

Thanks Terry. Appreciate your help.

Yes, the schematic is tough on the eyes, even printed on 11x17. Photofact is on it's way.

Paul
#4

   
Beitmans
#5

Tnx David,
Both Riders I looked up were pretty poor. Forgot abt Beitmans.

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
#6

There were a few discrepancies between the schematics but the culprit was the a bad volume pot.

Paul




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