Stylophone

The Stylophone is a miniature analog stylus-operated keyboard. Invented in 1967 by Brian Jarvis, it entered production in 1968, manufactured by Dubreq. It consists of a metal keyboard played by touching it with a stylus—each note being connected to a voltage-controlled oscillator via a different-value resistor—thus closing a circuit. The only other controls were a power switch and a vibrato control on the front panel beside the keyboard, and a tuning control on the rear. Some three million Stylophones were sold, mostly as children's toys.