AA5 6

Posted on Feb 6, 2014

The common wiring method had one side of the line cord going to a pin on the rectifier tube and the other side going to one terminal of the on/off switch. The other terminal of the on/off switch went to chassis. Suppose you plugged it in so the chassis was `cold` when the radio was turned on. That would mean that the bottom prong of the plug was c

AA5 6
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onnected to the power line neutral. Everything would be fine until you turned the radio off. Now the top prong of the plug is connected to the hot side of the power line. The tube heaters are cold and have a very low resistance (very approximately 100 ohms). This resistance is connected from the hot side of the power line to the chassis of the radio. You could connect a clip lead from the radio chassis to a water pipe and the radio would come on and play. If part of your body should complete the circuit instead of a clip lead you might never play again. Before starting to modify the radio go to a discount store and buy a polarized 2 prong plug extension cord. They are usually a dollar or less. Cut away the old power cord but leave short pieces of it on the rectifier tube and switch. If the insulation is in good shape (not always the case in these old sets) leave enough wire to reach to the switch. If the insulation on the old cord is rotten replace it with a piece of wire cut from the extension cord. Decide how long you want the new cord on the radio to be and cut the cord that length from the plug end. You will most likely never find a use for the socket end so cut off the extra cord, save it, and throw the socket end away. Thread the new cord in through the chassis hole. Position the end of the cord near where it is to be connected, the on/off switch and rectifier tube. Leave enough extra to be sure it will be long enough...

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