Audion Audion The Audion was an electronic detecting or amplifying vacuum tube invented by American electrical engineer Lee de Forest in 1906. It was the first triode, consisting of an evacuated glass tube containing three electrodes: a heated filament, a grid, and a plate. It is important in the history of technology because it was the first widely used electronic device which could amplify; a small electrical signal applied to the grid could control a larger current flowing from the filament to plate. The original triode Audion had more residual gas in the tube than later versions and vacuum tubes; the
Alexander Russell (electrical engineer) Alexander Russell (electrical engineer) Alexander Russell, FRS (15 July 1861 – 14 January 1943) was a Scottish electrical engineer and educator. He was born in Ayr, Scotland and educated at Glasgow University (gaining an MA in Mathematics and Physics) and Caius College, Cambridge. He was later (in 1924) awarded a doctorate. After teaching mathematics at Cheltenham College and the Oxford Military College, he took a post at Faraday House, in Southampton Row, London, which had been newly founded to train electrical engineers. In 1909 he became the Principal, a position he held until 1939. There he pioneered the sandwich course,