The 0B2 is a B7G voltage stabilizer and the design was one of the last produced before these devices were made obsolete by the Zener diode.

The regulation of the 0B2 was 3.5 Volts for currents of between 5 and 30 mA. So the voltage across this tube in service would have been held at between 106 and 110 volts. The tube strikes at a voltage of 133 volts.

The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 57 mm tall.

 
Pin Connections

B7G	1	2	3	4	5	6	7
	a	k	ic	k	a	ic	k

 
Absolute Maximum Operating Conditions

Stabiliser	Va	mAa
	108	30

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 12 June 2007 {find valves by name}