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shot effect

noun Electronics.
  1. random fluctuations in the emission of electrons from a hot cathode, causing a hissing or sputtering sound (shot noise) in an audio amplifier and causing snow on a television screen.

Origin of shot effect

translation of German Schroteffekt (1918), equivalent to Schrot small shot, buckshot + Effekt effect
Also called Schottky noise.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018