This valve is a small (triode) hydrogen thyratron for pulse modulator duty. It would work with a peak anode voltage of 3 kV and a pulse power of 60 kW.

It was originally used in some WW2 small airborne radars but remained in the lists until the late 1970s.

The commercial equivalent type is FX227.

In-service life was rather short so the valves had to be replaced quite frequently. There are plenty of relatively modern specimens around, mostly in unused condition, but WW2 originals are now rare. Modern specimens include a small hydrogen reservoir cylinder absent in the originals.

The electrodes are firmly held, and the stout wire to the top cap is insulated by glass. The filament is vertical within the anode. The construction has a pressed glass base.

The envelope is 36 mm in diameter and, excluding the UX4 base pins, is 106 mm tall.

 
Absolute Maximum Operating Conditions

Thyratron	Vh	Ah	Va	mAa
	6.3	2.7	3,000pk	50

This exhibit was last updated on 02 August 2006