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Philco 40-180 - Resistor Burnout
#1

Hello, 

After cleaning the chassis installed a new dial light and cord, I replaced all paper caps, electrolytic caps, and some crumbling wiring. I powered up the unit via a dim bulb tester and everything seemed to be coming to life ok. Then the 4700 ohm resistor (#29) tied to the 6J8G DET-OSC tube began to smoke! I shut down the unit, replaced the resistor and began to troubleshoot.

I rechecked all other resistors and made sure all caps were correctly wired.

I removed the 6J8G and the resistor still got very hot - shut the unit down - checked the make sure the resistor was still good.

I replaced the 6J8G and removed the 1232 tube and the resistor still got very hot - checked the make sure the resistor was still good.

I replaced the 1232 and removed the 7B7 tube and the resistor still got very hot - checked the make sure the resistor was still good.

I replaced the 7B7 and tore apart the IF can (#30) and replaced the old rubber wires.

Powered the unit up and the resistor still got very hot.

Please let me know what next steps I could take to figure out where the problem is.

Many thanks!


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Messages In This Thread
Philco 40-180 - Resistor Burnout - by wtoeller - 12-15-2021, 06:54 PM
RE: Philco 40-180 - Resistor Burnout - by Mondial - 12-15-2021, 09:43 PM
RE: Philco 40-180 - Resistor Burnout - by Mondial - 12-16-2021, 10:25 AM
RE: Philco 40-180 - Resistor Burnout - by RodB - 12-16-2021, 02:42 PM
RE: Philco 40-180 - Resistor Burnout - by Mondial - 12-16-2021, 06:08 PM
RE: Philco 40-180 - Resistor Burnout - by Mondial - 12-16-2021, 06:20 PM



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