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Low voltage and oscillation
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Hi all  I am working on a Philco 40-190.  
 I checked the power transformer for resistance in the windings before testing to see if it's any good.
Resistance on the pri. and sec. Filament windings was good. Resistance on the HV Sec. was supposed to be 170 ohms from 1 side to CT and 180 ohms from other to CT.  Mine were 125 and 135.  I didn't think too much about it and went ahead and changed all caps and 80% of res. and 90% of the rubber wire.
 Came time to power it up and Filament voltages are right on but HV sec. voltages are all low.  All plate voltages are 35-40 volts low from the rectifier to the RF 1232 tube.

 So I guess my questions are: 
1.  Would this low voltage affect the function of the IF cans because I'm getting fluctuating oscillation?
2.  Would this low voltage affect the function of all the tubes and the osc transformer?
3.   Does anybody have any suggestions ?

I was picking up stations for a time but as soon as I tried to align I lost all oscillation.  I read a post from Ron that said the IFs can go bad in these sets- can you cook them or rebuild them?
Sorry this is kind of a flighty post but frustration can get the best of us.  Thanks ahead of time.

Dick


Messages In This Thread
Low voltage and oscillation - by madsowry - 03-11-2019, 07:01 PM
RE: Low voltage and oscillation - by morzh - 03-11-2019, 08:52 PM
RE: Low voltage and oscillation - by madsowry - 03-11-2019, 10:42 PM
RE: Low voltage and oscillation - by Chas - 03-12-2019, 11:58 AM
RE: Low voltage and oscillation - by madsowry - 03-12-2019, 05:26 PM
RE: Low voltage and oscillation - by Chas - 03-12-2019, 06:08 PM
RE: Low voltage and oscillation - by madsowry - 03-12-2019, 11:14 PM



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