8 Nov
2007
8 Nov
'07
10:47 a.m.
On Wednesday 07 November 2007 19:17, Tony Duell wrote:
This may be a UK .vs. US language difference, but to me :
A 'filament' is a thin wire, heated electircally. A heater (in a valve)
is a particular type of filament
A filament that's also the cathode (as here) is a 'directly heated cathode'
A filament that heats a separate cathode is called a 'heater'. The result
is caleld an 'indirectly heated cathode'
-tony
That's always been the way I understood it as well, so I don't think we're
dealing with any across-the-pond language differences here...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
[...] the two wires that are a filliment (heater to
some).
As I understand it, a filament and heater are not just two different
words for the same thing (for a long time I thought they were...).
A filament is what this is: the electron emitter is the same thing that
is generating the heat through ohmic losses. A heater is a case where
the heat generator is not the same thing that is emitting electrons, as
in many vacuum tubes: the heater generates heat, which then warms up
the (separate) cathode electrode.