24 Mar
2006
24 Mar
'06
1:54 p.m.
On 3/24/2006 at 8:16 PM ard at p850ug1.demon.co.uk wrote:
Nobody's mentioned thyratrons (gas-filled
triodes/tetrodes) either. I
suspect the thyratrons used in ring counters, etc, were always inert gas
(and not mercury vapour) ones, does anyone know for sure?
There are small ignitrons that use mercury vapor. There are also ignitrons
that use sodium vapor.
I love the old names for thermionic devices; we've lost that knack for
naming. Any gas-filled thermionic diode is a phanotron, any vacuum-filled
diode is a kenotron. So an 866 is a phanotron (has mercury), but a 5U4 is
a kenotron. A vacuum triode is a pliotron and a gas triode is a thyratron.
Ya gotta love it!
--Chuck