Radio receiver crude triode, was invented in 1906 by Lee De Forest as a more sensitive detector for radio receivers, by adding a third electrode to the thermionic diode detector, the Fleming valve. It was not widely used until its amplifying ability was recognized around 1912. The first tube receivers, invented by De Forest and built by hobbyists until the mid 1920s, used a single Audion which functioned as a grid-leak detector which both rectified and amplified the radio signal. There was uncertainty about the operating principle of the Audion until Edwin Armstrong explained both its amplifying and demodulating functions in a
William McLellan (American electrical engineer) William McLellan (American electrical engineer) William Howard McLellan (December 1, 1924 – September 30, 2011) was an American electrical engineer, who achieved some fame in 1960 by succeeding at an engineering challenge set by Nobel Prize-winning physicist Richard Feynman. McLellan was born in Casper, Wyoming, grew up in Orland, California, and fought in the Canadian Army in the Second World War. He met his wife Patricia Price in England during the war, and afterwards the couple settled in Pasadena, California, where McLellan attended California Institute of Technology (Caltech). In December 1959, Feynmann offered two challenges relating to nanotechnology at the