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
Arthur Williams (electrical engineer) Arthur Williams (electrical engineer) Arthur Williams (August 14, 1868 – April 14, 1937) was an American electrical engineer, executive at the New York Edison Company, Federal Food Administrator of the City of New York, and first president of The National Association of Corporation Schools in 1913. Williams was born in Norfolk, Virginia in 1868, the son of Rev. Christopher S. and Hannah Sanford (Rogers) Williams. He was educated in the public and private schools of Hartford, Conn., and New York City. At the age of sixteen, in 1882, he began his business career with an electrical contractor. He remained in