Crystal radio was the pioneer of early radio receivers, though it is almost forgotten now. A crystal radio needs no battery or power and works on the microvolts of radio signals received from its antenna. It is named for its most important component, a crystal detector, which was originally a piece of crystalline mineral; nowadays a diode is used. This compilation includes 3 different models, showing you how to make one from scratch with simple materials you could purchase from a local hardware store and no prior knowledge necessary. These free energy communication devices use short and medium wave AM (amplitude modulated) and can be used to chat with ham radio operators.

90-min. DVD