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
Bob Adams (electrical engineer) Bob Adams (electrical engineer) Robert Whitlock Adams is a Technical Fellow at Analog Devices, Inc. (ADI) in Wilmington, Massachusetts. His focus is on signal processing and analog-to-digital conversion for professional audio. He is a leader in the development of sigma-delta converters, introducing architectural advances including mismatch shaping, multi-bit quantization, and continuous-time architectures. Adams graduated with a Bachelor of Science in Electrical Engineering from Tufts University in 1976. From 1977 to 1988 he worked for DBX, a professional audio recording company. There, he helped develop the industry's first audio converter with greater than 16-bit resolution, as well as one of the