A calendar kept by Fessenden at the time does not mention it, and there are no newspaper accounts, even though a similar exercise conducted the next spring by rival Lee De Forest
created a nationwide stir.
Dear Editor, Chris You-ett's revelation (Memory stack of facts on computing, Post, Jan 12) that the thermionic valve was invented by Prof Tommy Flowers in 1938 will cause surprise, not to say consternation, among those of us who have long believed that it was the work of Sir Ambrose Fleming in 1904 and also of Doctor Lee de Forest
In 1906, American engineer Lee De Forest
patented the triode vacuum tube.
As early as 1910 Lee de Forest
aired the voices of Enrico Caruso, Olive Fremstad, Pasquale Amato, and Emmy Destinn in experimental transmissions from the Met, but the audiences were limited to the handful of listeners within fifty miles of New York City who were fortunate enough to have access to a radio receiver.
That range was extended in 1906 by the American inventor Lee De Forest