![Example of single tube triode grid-leak receiver from 1920, the first type of amplifying radio receiver. In the grid leak circuit, electrons attracted to the grid during the positive half cycles of Example of single tube triode grid-leak receiver from 1920, the first type of amplifying radio receiver. In the grid leak circuit, electrons attracted to the grid during the positive half cycles of](https://c8.alamy.com/comp/P6NEFR/example-of-single-tube-triode-grid-leak-receiver-from-1920-the-first-type-of-amplifying-radio-receiver-in-the-grid-leak-circuit-electrons-attracted-to-the-grid-during-the-positive-half-cycles-of-the-radio-signal-charge-the-grid-capacitor-with-a-negative-voltage-of-a-few-volts-biasing-the-grid-near-its-cutoff-voltage-so-the-tube-conducts-only-during-the-positive-half-cycles-rectifying-the-radio-carrier-P6NEFR.jpg)
Example of single tube triode grid-leak receiver from 1920, the first type of amplifying radio receiver. In the grid leak circuit, electrons attracted to the grid during the positive half cycles of
![Behind The Front Panel: The Design & Development of 1920's Radio: Rutland, David, Watts, Richard: 9780991126002: Amazon.com: Books Behind The Front Panel: The Design & Development of 1920's Radio: Rutland, David, Watts, Richard: 9780991126002: Amazon.com: Books](https://images-na.ssl-images-amazon.com/images/I/51GNYjER%2BHL._SR600%2C315_PIWhiteStrip%2CBottomLeft%2C0%2C35_PIStarRatingFOURANDHALF%2CBottomLeft%2C360%2C-6_SR600%2C315_ZA11%2C445%2C290%2C400%2C400%2CAmazonEmberBold%2C12%2C4%2C0%2C0%2C5_SCLZZZZZZZ_FMpng_BG255%2C255%2C255.jpg)
Behind The Front Panel: The Design & Development of 1920's Radio: Rutland, David, Watts, Richard: 9780991126002: Amazon.com: Books
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