On Thu, 11 Nov 2004 22:12:10 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Arny Krueger wrote:
If you attribute it to Guthrie than its 100th anniversary was in 1973.
If you attribute to Edison, then it was 100 years old in 1880. If you
attribute it to Richardson who won a Nobel prize related to it, then
you've got about 19 years to go.

Fleming patented his related discovery the diode, in 1904.

The radio today reckoned Edison commissioned Fleming to find out why a
carbon filament lamp coated the inside of the glass. And this led to the
discovery that adding a metal plate cause a current to flow in it.

However, it was Edison who first noted the diode effect, but had no
use for it in 1880. It only had a practical application after Marconi
radio transmitters became popular, and more sensitive AC detectors
were needed. After that, Lee de Forest invented the triode - or did
he? :-) - and the whole electronics industry kicked off.
--

Stewart Pinkerton | Music is Art - Audio is Engineering