The EA76 was one of the first of the robust miniature types that were introduced by Mullard in 1950.

This ultra miniature diode has an indirectly heated cathode and the bright anode is 9 mm long including the supporting mica insulators.

The advert above says this range were originally developed for guided missile applications and would become available commercially in 1953.

The flying leads form a five pin base known as the B5B the /F suffix denoting the flying leads. The anode has side flanges and the cathode passes through a rectangular gap.

The thin glass tube envelope is 5 mm in diameter and, excluding the base wires is 28 mm tall.

Reference: Datasheet. Type EA76 was first introduced^¶ in 1953.

 
Absolute Maximum Operating Conditions^¶

Diode	Vh	Ah	Va	mAa
	6.3	0.15	150	9.0

Thanks to Frank Philipse for supplying the above PDF datasheet