cat whisker

electronics

Also known as: cat’s whisker

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Last updated

June 24, 2026

Quick Summary

In electronics, a "cat whisker" refers to a fine wire that makes contact with a crystal in certain types of radio and electronic circuits. This component was crucial in early radio technology.1

Greenleaf Whittier Pickard, an electrical engineer, is credited with discovering that the contact between a fine metallic wire (the "cat whisker") and certain crystalline materials, like silicon, could rectify and demodulate high-frequency alternating currents. This led to the invention of the crystal detector, a key part of early radio receivers known as crystal sets. The crystal detector was a precursor to the transistor.2

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electronics
The vacuum tube era
…devices such as the “cat whisker” detector, which was composed of a fine wire (the whisker) in delicate contact with the surface of a natural crystal of lead sulfide (galena) or some other semiconductor material. These devices were undependable, lacked sufficient sensitivity, and required constant adjustment of the whisker-to-crystal…
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…devices such as the “cat whisker” detector, which was composed of a fine wire (the whisker) in delicate contact with the surface of a natural crystal of lead sulfide (galena) or some other semiconductor material. These devices were undependable, lacked sufficient sensitivity, and required constant adjustment of the whisker-to-crystal…
Read More

solid-state device
…solid-state device was the “cat’s whisker” (1906), in which a fine wire was moved across a solid crystal to detect a radio signal. Transistors, made of one or more semiconductors, are at the heart of modern solid-state devices; in the case of integrated circuits, millions of transistors can be…
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…solid-state device was the “cat’s whisker” (1906), in which a fine wire was moved across a solid crystal to detect a radio signal. Transistors, made of one or more semiconductors, are at the heart of modern solid-state devices; in the case of integrated circuits, millions of transistors can be…
Read More

Greenleaf Whittier Pickard
…contact between a fine metallic wire (“cat whisker”) and the surface of certain crystalline materials (notably silicon) rectifies and demodulates high-frequency alternating currents, such as those produced in a receiving antenna by radio waves. This device, called a crystal detector and patented by Pickard in 1906, was an essential component…
Read More
…contact between a fine metallic wire (“cat whisker”) and the surface of certain crystalline materials (notably silicon) rectifies and demodulates high-frequency alternating currents, such as those produced in a receiving antenna by radio waves. This device, called a crystal detector and patented by Pickard in 1906, was an essential component…
Read More