How to Make/Build a Crystal Radio

Step-by-step instructions for making a tunable crystal radio. This is a radio that gets its power from the radio waves. I made it almost entirely from junk except for the diode (1N34 germanium diode) and the earpiece (though you can use a speaker from a phone instead.) The capacitor is made from aluminum foil and a paper towel roll. The coil is rolled on a toilet paper roll. The wire is enameled magnet wire. For the antenna I use a 15 foot wire laid out on the floor. For the earth ground I connect a wire to the ground in the household wiring. I originally got this circuit from the book “Radio Receiver Projects You Can Build“ by Homer L. Davidson. For this circuit, the diode must be germanium. The following is a partial list of germanium diodes that should work: 1N34A, 1N60, 1N91, 1N119, 1N270, 1N277, 1N283 The following are not germanium diodes and may need a long antenna or a powerful radio station nearby to work: 1N4148 (silicon, found on a lot of circuit boards), B16 (