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
Charles Brown (engineer) Charles Brown (engineer) Charles Brown (1827–1905) was a British engineer. He was born at Uxbridge on 30 June 1827 and was apprenticed to Maudslay, Sons and Field. In 1851 he moved to Switzerland to join the Sulzer company. In 1871 he left Sulzer to set up Swiss Locomotive and Machine Works (SLM). While at SLM he invented the Brown valve gear, a radial valve gear for steam engines. He became involved in the development of electric locomotives in the 1880s. In 1885 he became manager of Maschinenfabrik Oerlikon and in 1890 he set up Charles Brown and Company at 91