12-31-2011, 06:46 PM
I ran into a problem on a Philco 70 one time, that liked to drove me nuts. If I remember right, I had re caped the radio and rewound one of the coils. The radio was playing beautifully, I put it back in the cabinet, just to have it quit a couple of hours later. I removed the chassis again, before I could do anything to it, it started working again. I let it play on the bench for two or three days, so I put it back in the cabinet. You guessed it! Well, this went on for five or six times. Put the chassis in the cabinet, just to have it quit working anywhere from twenty minutes to two days later. Take it out and it would work without fail. The problem turned out to be one of the trimmers for one of the IF transformers. This is what I found. These trimmers are put together with a hollow brass rivet. The mounting bolt passes through the rivet and the ground is provided by the mounting bolt. Well, the back plate of the trimmer is made of steel and had rusted under the flange of the rivet, causing an intermittent connection. I mention this because, this could happen to any of the old Philcos and cause some strange problems.
Steve
Steve
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