Radio receiver crude triode, was invented in 1906 by Lee De Forest as a more sensitive detector for radio receivers, by adding a third electrode to the thermionic diode detector, the Fleming valve. It was not widely used until its amplifying ability was recognized around 1912. The first tube receivers, invented by De Forest and built by hobbyists until the mid 1920s, used a single Audion which functioned as a grid-leak detector which both rectified and amplified the radio signal. There was uncertainty about the operating principle of the Audion until Edwin Armstrong explained both its amplifying and demodulating functions in a
Christopher Rose (electrical engineer) Christopher Rose (electrical engineer) Christopher Rose (born January 9, 1957) is a professor of engineering and associate dean of the faculty at Brown University in Rhode Island and a founding member of WINLAB at Rutgers University in New Jersey. He was educated at the Massachusetts Institute of Technology; SB'79, SM'81, Ph.D'85 all in Course VI (Electrical Engineering and Computer Science). On September 2, 2004, an article by Christopher Rose and Gregory Wright, titled "Inscribed matter as an energy-efficient means of communication with an extraterrestrial civilization", appeared on the cover of "Nature" with the headline "Dear ET...". The article argued that