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Old 08-08-2014, 01:43 AM
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Tubejunke Tubejunke is offline
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Join Date: Apr 2003
Location: Martinsville, VA
Posts: 1,823
40s Philco 40-145 BUMMER!

We live and we learn. I lucked out and bought this rather nice art deco Philco several years ago in working condition for a song. Even if a radio works, I like to remove the chassis and blow the dust out and clean the tubes and pots, so I did. Well, like an idiot I did that and replaced the tubes with two in swapped positions! I am fairly certain that I had the 7Y4 rectifier in the 7B5 output socket and vice versa.

NOT a good result! The radio was only plugged in that way for a matter of seconds as all it did was produce a full volume hum. Once I realized what I had done I tested the tubes and put them in the right sockets, but the radio has never been right since. Back then I went ahead and replaced the filter capacitors hoping that what I was hearing was just a coincidental failure of the filters in a very old radio. New filters helped with the hum, but the radio still fails to pick up anything and often takes to loud motor-boating until I touch one of four or five antenna terminals which by the way are not connected to their spaghetti mess of wires.

I also found the .5 Meg volume pot to be open due to worn away carbon at both outside terminals, so I replaced that. What noise I it produces if I tamper with the antenna terminals does not seem to be volume adjustable. I guess swapping in a rectifier to where an output tube is could have done anything. Nothing smoked I will say, but that doesn't matter really, but without burning up a resistor or capacitor you would almost think that no damage was really done to the components.

I hope to get this one going as it is a really nice piece with the pushbuttons and all. I'm so mad at myself because I can remember trying it when I bought it and it played wonderfully on AM and Shortwave.....
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