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Old 09-04-2015, 02:37 PM
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TheShanMan TheShanMan is offline
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GE T265A sound cutting out

When this 60's era radio first warms up it sounds just fine, but then after about a minute it starts cutting out more and more until a short while later you get nothing. But if you turn the volume up fully you can hear the station VERY faintly.

I haven't dug too far in yet but I have tapped components and wiggled tubes while the problem is occurring (not to mention turning the knobs) so I don't get the impression the problem is a cold solder joint or tube connector.

Since I'm pretty new to the world of tubes I'm not sure if this sounds like a failure pattern for a faulty tube or if I ought to be looking elsewhere. Seems like it must be a problem in the amplifier circuit though. I'm curious what people think is the best way to move forward.
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Old 09-05-2015, 02:37 AM
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Electronic M Electronic M is offline
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If you got a audio generator. Connect it to the set's first audio stage before it fades and after. If no change RF issue, but if it fades AF issue. A can of freeze spray might help the troubleshooting.
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Old 09-05-2015, 02:46 AM
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Has it been recapped? Leaky caps could be the sole problem.
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Old 09-05-2015, 09:49 AM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Findm-Keepm View Post
Has it been recapped? Leaky caps could be the sole problem.
A strong possibly, bad IF transformer, silver mica disease, especially if it has GE made transformers.
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Old 09-11-2015, 10:50 PM
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I don't have a generator. I've recapped just the electrolytics. I'm curious what the problem would be with a bad transformer and/or what the solution would be. Would I just be looking for continuity on both the input and the output or is there more to it than that?
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