A woman phones up her husband at work for a chat.
HIM "I'm sorry dear but I'm up to my neck in work today."
HER "But I've got some good news and some bad news for you dear."
HIM "OK darling, but as I've got no time now, just give me the good news."
HER "Well, the air bag works."
First Audion tubeIn 1906, the first triode was ordered by Lee de Forest who instructed the New York automobile lamp maker, H. W. Candless, to make a glass bulb containing a "grid" wire between a filament and an electrode plate. These specifications extended the Fleming two-element diode valve design previously published in the Proceedings of the Royal Society. The third element - the grid wire - regulated the flow of electrons between the filament and the anode plate, producing an amplification of the variations in a signal voltage applied to the grid. De Forest named his invention the "Audion." Within a few years (1913-1917) he was able to profit from his patents that he sold to AT&T for a total of $390,000.«[Image: A de Forest Audion tube, circa 1912.] |
