Ignitrons are
very different beasts from thyratrons.
They're both gas-filled power-control devices performing similar functions.
Mmmm...sort of. After a few beers.
Thyratrons can contain gases or mercury (or I think, in some case,
both), and they still use a filament, much like a normal tube
(pliotron or kenotron, if any GE people are keeping score) and some
sort of grid for control, although in many thyratrons the grid looks
nothing like a grid. Thyratrons are used for control rather than
rectification, although one can rectify with them (IBMs power supply
for the 709 - they were likely used to give some sort of help in
regulating the DC output).
Ignitrons use mercury (I have never heard of one that does not,
although krytrons are pretty similar) and do not have filaments. The
conductor is the mercury plasma created by the igniter arc, and
conduction is more or less the arc between the pool and the anode.
Ignitrons tend to be used more for rectification than control(and when
used for control, they tend to be simple on-off, rather than the more
sophisticated setups thyratrons are often see with).
--
Will
