Valve amplifier thermionic valves. The simplest valve was invented by John Ambrose Fleming while working for the Marconi Company in London in 1904 and named the diode, as it had two electrodes. The diode conducted electricity in one direction only and was used as a radio detector and a rectifier. In 1906 Lee De Forest added a third electrode and invented the first electronic amplifying device, the triode, which he named the "Audion". This additional "control grid" modulates the current that flows between cathode and anode. The relationship between current flow and plate and grid voltage is often represented as a series
David Davies (electrical engineer) (IEE) 1996-2001, President of the Royal Academy of Engineering He has subsequently been Chairman of Railway Safety, a non executive director of Lattice plc, a non-executive director of The ERA Foundation, Chairman of the Hazards Forum (2002-2010), and safety advisor to the Board of National Grid plc. The Sir David Davies building at Loughborough University, housing the electrical engineering department, is now named after him. David Davies (electrical engineer) Sir David Evan Naunton Davies , known as Den Davies or David "DEN" Davies, (born 1935) is a British electrical engineer and educator. He was knighted for services to science in