The PHILCO Phorum
Model 80 Antenna Issue? - Printable Version

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Model 80 Antenna Issue? - Hamilton - 05-18-2025

https://philcoradio.com/library/download/service%20info/service%20bulletins/Philco%20Service%20Bulletin%20140.pdf

I’ve replaced all the caps and resistors and the radio is working but minimal volume unless I put my hand near the rear of the chassis. The radio then comes to life. I know I’m acting as an antennae but is this a sign that the antennae coil needs to be rewound? I’m not very good at troubleshooting.

Am I on the right path or what other items should I check. I realize this is simple stuff for most of the members but not for me. Any advice would be appreciated.

RE: Model 80 Antenna Issue? - RodB - 05-18-2025

You are kind of on the right path. You can touch the grid cap of the Detector/Oscillator 36 tube. I'm expecting a response of the radio sounding normal. Doing this bypasses the antenna transformer and the volume control. If you get the same response by touching the center terminal of the volume control then the antenna transformer is OK. If not, one of the coils of the transformer is open and you can use a meter to test for that. If the transformer is fine then the problem is with the volume control. You can either open it and clean it with Deoxit F5 or you can spray the cleaner into the control and work the shaft back and forth.

RE: Model 80 Antenna Issue? - Hamilton - 05-19-2025

I did as you suggested and touching the middle of the volume control did nothing so the coil has to be rewound. Any idea as to the appropriate size of wire to use for replacement?

RE: Model 80 Antenna Issue? - GarySP - 05-19-2025

Hello Hamilton, here is a little information found in our Philco Radio Library at the bottom of the Home page. Hope it helps! Take care, - Gary
https://philcoradio.com/library/index.php/shop-talk/techniques/rewinding-philco-coils/

RE: Model 80 Antenna Issue? - Hamilton - 05-19-2025

Thanks Gary and Rod. 

I also found an article in the Philco Repair Bench under Service Hints and Tips, about installing a “gimmick” wire on the Model 80. It also is supposed to improve the radios performance. 

It said to install a wire from the cathode of the 36 tube to the centre lug of the volume control and then to “adjust the detector/ oscillator cathode resister and capacitor as shown below” Trouble is the photos on that page don’t load on my ipad.  Does anyone happen to have that photo of that adjustment available?