Help with radio problem - Printable Version

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+--- Thread: Help with radio problem (/showthread.php?tid=1321)

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Help with radio problem - Guest - 08-24-2008

Hi all, I hope someone will be able to help me here. I have a Philco model 91L, type 127. It's a low boy console. I recapped, checked resistors, etc. about twenty years ago. Anyway, I had it on the other night and suddenly the audio just stopped. I turned it off and back on and it seemed fine for about 15 minutes. The audio just stopped again; while going over to the radio, I noticed a blue/purple glow from the back of it. There was no odor at all nor did I hear any arcing or the such. I removed the chassis today and gave it a very close visual inspection which showed nothing at all. I'm afraid to turn it back on as I may do damage to it. Does anyone know what may cause this problem? Any help would be greatly appreciated.

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- Terry Burns - 08-24-2008

Hi Tim,
Just a guess but I think I would look for a gassy tube in the audio section. My guess would be in the first amplifier. They produce a blue or purple glow when this happens. I don't think it would hurt to bring it up to look for it if you had some kind of limiting device such as a variac or a dim bulb tester. Good luck

Terry

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The purple glow - AI2V - 08-24-2008

If the high voltage is drawing too much current, the rectifier tube will often glow purple.

Your problem could be almost anywhere. I would pull and reinsert each tube to see if the purple goes away. That might get you to the circuit. Old components tend to break down over the years and develop leakage at high voltage.

If you get really desperate, I'm over here near Morristown and available most of the time. Parts, tubes, and equipment are here too.

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