Gimmick capacitor

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A gimmick capacitor is a capacitor made by twisting two pieces of insulated wire together. The capacitance may be varied by loosening or tightening the winding. The capacitance can also be reduced by shortening the twisted pair by cutting. The available capacitance is on the order of 1pF/inch (0.4 pF/cm). [1]

Capacitor electrical component used to store energy for a short period of time

A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance. While some capacitance exists between any two electrical conductors in proximity in a circuit, a capacitor is a component designed to add capacitance to a circuit. The capacitor was originally known as a condenser or condensator. The original name is still widely used in many languages, but not commonly in English.

Refs

  1. "... twisted-pair wire makes an excellent variable capacitor, sometimes called a gimmick" Pease, Robert A. (1991). Troubleshooting Analog Circuits (1st ed.). Butterworth-Heinemann. p. 22. ISBN   0-7506-9184-0.

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Gimmick is a novelty feature in marketing, magic/illusion, and psychology.

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