Triode Triode A triode is an electronic amplifying vacuum tube (or "thermionic valve" in British English) consisting of three electrodes inside an evacuated glass envelope: a heated filament or cathode, a grid, and a plate (anode). Developed from Lee De Forest's 1906 Audion, a partial vacuum tube that added a grid electrode to the thermionic diode (Fleming valve), the triode was the first practical electronic amplifier and the ancestor of other types of vacuum tubes such as the tetrode and pentode. Its invention founded the electronics age, making possible amplified radio technology and long-distance telephony. Triodes were widely used in consumer
William Bryson (electrical engineer) William Bryson (electrical engineer) William Alexander Bryson FRSE (2 March 1855 – 9 July 1906), was a Scottish electrical engineer. He was born on 2 March 1855, the son of Alexander Bryson and Elizabeth W. Gillespie. His grandfather was Robert Bryson. His mother died shortly after he was born, and his father, who remarried twice in the meantime, died when he was aged 11. He trained and worked as a Marine Engineer in Leith, and then moved to Glasgow as a consulting Electrical Engineer. There is a sketch of him by John Lavery in the Glasgow Museum Resource Centre. He