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How to make a theremin
Learn the essential components of the theremin.
A theremin is basically a box with two antennas, one of which controls the pitch of the instrument, the other of which controls the volume. These antennas create electromagnetic fields which are " played " by manipulating them with the hands.
Coils of tight-pack wire act as oscillators, producing signals fed into the antennae. While it may seem like spooky magic, the fields are created by relatively straightforward circuitry.