Upon the date 11:19 PM 8/15/99 +0100, Tony Duell said something like:
One might
argue that a neon bulb or a decatron isn't properly a "tube"
(they certainly aren't "valves" because they don't have a control grid
like a triode), but they are non-linear devices that are capable of
storing (and displaying) state information and performing simple logic
functions.
Question for the UKer's: is a tube rectifier (no control grid, just
an anode and a cathode) called a "valve"? Is a voltage regulator tube (like
the venerable OA2) called a "valve"?
Hmmm...
Rectifiers are called 'valves' (so we'd talk of a EZ81 valve or a 5U4
valve). I guess you think of them like the one-way valve on a tyre :-).
Indeed, or like a hose bib of which you would attach a garden hose or the
device mounted on your bathtub either of which allow you to control the
flow of water. Fleming evidently thought of his invention as a one-way flow
controlling device, or *valve*, except electron flow was the medium
controlled. Hence, my suspicion he chose the word valve based on that
function his invention performed. Later, with a third element called a
control grid which DeForest purportedly invented in conjunction with his
Audion patent of 1906, one could then truly control the quantity of flow of
electrons through that one-way device called a valve.
To get this even _nearly_ on topic, the transistors in today's IC's are
like "valves", so our computers have millions of little "valves" in
them
(how's that for a stretched topic? :)
I think we'd probably call an OA2 a 'valve' as well, although talking
about 'stabiliser tubes' or 'cold cathode tubes' seems to be common usage
in UK books as well (as is 'stabiliser valves' and 'cold cathode
valves').
We certainly talk about 'counting tubes' when refering to dekatrons,
trochatrons, etc. Never seen them called 'counting valves'. And CRTs are
certainly 'tubes' over here.
Probably the USA expression "tube" was adopted to differentiate between a
'controlled' valve (diode, triode, tetrode, etc.) and these more recent
thermionic emission devices you speak of. But I would have called a CRT a
Cathode Ray Valve (CRV) because of its function. However, V. Zworykin had
perfected in the USA that device which presents an image on a phosphor
screen mounted on a glass envelope under vacuum which we all call the CRT.
Hence the "T" for Tube in CRT. Interesting how the region in which an
invention is made can affect the invention's name.
Regards, Chris
-- --
Christian Fandt, Electronic/Electrical Historian
Jamestown, NY USA cfandt(a)netsync.net
Member of Antique Wireless Association
URL:
http://www.antiquewireless.org/