RE: Still more H2 Thyratron

Hi Bert:

I understand the basics of SCR operation, but it's not clear if the turn-off
criteria for thyratrons is met with each tank circuit voltage reversal,
which would be exactly what we want.  Is it, or is such rapid turn-off
behavior limited to just the most exotic thyratrons?

Gary Lau
Waltham, MA USA

		Original Poster: Bert Hickman <bert.hickman-at-aquila-dot-com> 

		Hydrogen thyratrons are used for high voltage, moderate
		switching, where the average current levels are
comparatively low. When
		combined with a DC charging source and HV pulse forming
network, they
		can be used to provide pulsed power for high-energy
experiments or for
		pulsed RF (RADAR, partical acellerators). A thyratron is the
vacuum tube
		analog to a Silicon Controlled Rectifier (SCR) - once turned
on, current
		flow through the device must be stopped or the applied
voltage reversed
		in order to turn off the device. A thyratron is triggered by
a positive
		pulse on the control grid, which is normally biased to a
negative DC
		potential versus the cathode. Once the thyratron begins to
conduct, the
		grid no longer has any control over the device