Fleming valve valve proved to be the start of a technological revolution. After reading Fleming's 1905 paper on his oscillation valve, American engineer Lee DeForest in 1906 created a three-element vacuum tube, the Audion, by adding a wire grid between cathode and anode. It was the first electronic amplifying device, allowing the creation of amplifiers and continuous wave oscillators. De Forest quickly refined his device into the triode, which became the basis of long-distance telephone and radio communications, radars, and early digital computers for 50 years, until the advent of the transistor in the 1960s. Fleming sued De Forest for infringing his
Vienna valve trombone The Vienna system was in common use in Germany on all kinds of instruments including trumpets up to 1850. Adolph Sax invented instruments with 6 independent valves 3 for each hand, but only the most dexterous musicians were able to play them. The valve trombone has definite advantages over the more common slide trombone, such as taking up less room in a seated orchestra. Verdi, for example, composed passages that would have been impossible on a normal slide trombone. For illustrations of a Vienna valve trombone c.1850, see: Vienna valve trombone Vienna valve trombones use Vienna Valves which were one