Thread: My new toy...
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Old 09-06-2008, 09:58 PM
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Jeffhs Jeffhs is offline
<----Zenith C845
 
Join Date: Feb 2003
Location: Fairport Harbor, Ohio (near Lake Erie)
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Quote:
Originally Posted by leadlike View Post
The radio itself is a Philco 38-7 chassis, and it is toast right now. The two lytic cans are all foamed over. Hopefully this won't be too rough of a restore. I typically find Philcos to be pretty tempermental to work on.
The first thing I'd do is replace those electrolytics, as they are obviously defective. I wouldn't be surprised if that's all that is wrong with the radio, although I'd want to know what overloaded the original caps so badly that they foamed. In 40-some years of electronics experimenting I have never seen can-type electrolytics do that. They are sealed, so where would the foam go? In the case of a well-sealed electrolytic capacitor, I would think they would explode, unless the seals are so bad by now that the cap is literally leaking electrolyte. I'd replace those caps ASAP and try the radio again; as I said, this may be just enough to get the radio working.

Also, defective filter caps in a transformer-powered radio could damage the transformer, so again, replacement of the defective parts should be the first thing done to this set before anything else, and certainly before applying power to the chassis.
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Collecting, restoring and enjoying vintage Zenith radios since 2002

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