This tetrode thyratron is built on a conventional glass pinch. The same valve from STC uses a glass disc base, the forerunner of the modern all glass construction.

The control ratio is high at 350 and the voltage drop across the tube when conducting is 9 Volts.

The classic envelope is 36 mm in diameter and, excluding the IO base pins, is 85 mm tall.

Reference: Datasheet. Type 20A2 was first introduced^¶ in 1957.

 
Pin Connections

IO	1	2	3	4	5	6	7	8
	-	h	a	-	g1	g2	h	k

 
Absolute Maximum Operating Conditions^¶

Thyratron	Vh	Ah	Va	mAa
	6.3	1.0	600	1,250

Thanks to Frank Philipse for supplying the above PDF datasheet

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