Construct a coil with a cardboard tube approx. 1 1/2&quot; in diameter and #22 enamel coated copper wire. Starting at one end of the tube, wrap 100 turns of wire, closely spaced. Connect all components together on a flat piece of plywood. When finished, connect one end of the coil to an outside antenna made up of approx. 100ft of wire  fastened between two trees or poles. Connect the other end of the coil to a cold water pipe in the house. With High Z  earphones you should get 1 or 2 stations. This radio requires no batteries.<p>
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