The 4687A is a voltage stabiliser tube. The 4687 is on a Ct8 base and this variant has the B4 base. Both have identical electrical characteristics.

The striking voltage is 130 Volts and the regulation is 6 volts across the full current range.

The wide glass tube envelope is 25 mm in diameter and, excluding the B4 base pins, is 86 mm tall.

 
Pin Connections

B4	1	2	3	4
	a	k	-	-

 
Absolute Maximum Operating Conditions

Stabiliser	Va	mAa
	100	10.0-40.0

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 02 July 2007 {find valves by name}