Quote:
Originally Posted by radiotvnut
Here's a circa '63 JVC-Delmonico AM/FM stereo Japanese tube radio, model FMS-413U, that I bought for $10 at the flea market. The lady said she plugged it in and she heard a loud POP, followed by a wisp of smoke. Once I removed the back, it didn't take long to see what blew up - the capacitor that's wired across the AC line. This is yet another example why people shouldn't plug in a tube radio without first having it checked/gone over by an electronics technician.
As you can see, this is an AC/DC radio and looks to have a 35C5 output tube for each channel. It will be interesting to see how this performs when it's restored.
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See Johnny (The Raster Master)'s post in the TV forums for an excellent example of what can and all too often does happen when a radio or TV is indiscriminately plugged into the AC line, without first replacing old filter caps.
Does the radio operate normally with the line bypass capacitor out of the circuit? I would think the reason the capacitor exploded in the first place was that it was shorted; of course, when these capacitors short, they put a direct short circuit across the AC line and will smoke, pop and explode just as you described. However, I am surprised the line fuse (if present) or the shop's circuit breakers didn't open as soon as the radio was plugged in.