coherer
Quick Summary
A coherer is an early electronic device used as a radio detector. Invented by Édouard Branly and later improved by Sir Oliver Lodge, it consists of a tube filled with conductive material, such as iron filings. When a radio-frequency voltage is applied, the material coalesces, or "coheres," allowing an electrical current to pass. This current could then operate a relay to reproduce Morse code signals. Guglielmo Marconi utilized a coherer in his early wireless telegraphy experiments, enabling transatlantic communication. The coherer had to be tapped to separate the filings between signals. It was eventually superseded by more advanced detectors.123
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Jagadish Chandra Bose…led to improvements in the coherer, an early form of radio detector, contributing to the development of solid-state physics.
Read More…led to improvements in the coherer, an early form of radio detector, contributing to the development of solid-state physics.
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Sir Oliver Joseph Lodge…British physicist who perfected the coherer, a radio-wave detector and the heart of the early radiotelegraph receiver.
Read More…British physicist who perfected the coherer, a radio-wave detector and the heart of the early radiotelegraph receiver.
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