As I was looking around at some of these nice little Arvin, Silvertone, and Temple metal-cabinet radios I remembered the potentially fatal designs used with non-OSHA approved radios (of course, OSHA wasn't around when these were made!). I also remembered TARC member Doug Wright holding a small metal Arvin while ankle deep in the water at TARC's Prince William Day outing. When he turned it on he was sure looking to turn it off. Doug was lucky, but his experience points out the serious nature of restoring and playing these sets.

When you restore these radios an isolation transformer is an absolute must. This will isolate you from ground hazard, but you can still get shocked from the 120 volts AC from the transformer.

As important as the isolation transformer during restoration is the polarized plug on the line cord. One blade or prong on the plug is larger than the other so the plug will only go in the socket one way, ensuring that the larger pin is connected to ground and not the hot wire. This is assuming that your wiring was done properly, and can easily be tested with one of those plug-in line testers which cost around $5.00 - another good investment. I was surprised to find it hard to locate two prong polarized plugs to make my own cords, so I went one better and visited a local Lamp Store where they stock and sell parts of all sorts for household lamps. I bought a great assortment of 8-foot cords with the two prong polarized plugs for $2.50 each. They had cream, brown, black, gold, and silver, all good colors for metal cabinet radios.

As one of the first steps in restoration of the small metal radios, the AC line cord should be replaced. Check your circuit diagram and see if one side of the cord is connected directly to the chassis or to a floating ground. Using a meter to determine continuity, connect the wire on your new line cord that goes to the larger pin to the side of the circuit that goes to the chassis. Then, when you finish restoration and turn the set on, the chassis, and by extension the metal cabinet, will be grounded and will protect you from a dangerous situation.

If you have a metal radio that is working you can place it on your bench, plug it in, turn it on, and using your meter set to the AC scale check for voltage from the cabinet to your utility neutral on your outlet - the larger of the two vertical pins or the round ground pin. Then reverse the plug and measure. If you get a reading at one of these positions you have a dangerous radio.

Don't Economize, Polarize!

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