The ECC70 represents the smallest all glass valves made for general use and dates from 1950. This double triode is of low impedance and moderate gain. The fact that Mullard made these valves in the 6021 special quality version suggests a military or industrial role. The wire ended construction would aid the building of small equipment.

The thin glass tube envelope is 9 mm in diameter and, excluding the B8D base pins, is 36 mm tall.

References: Datasheet & ¹⁰⁴⁰. Type ECC70 was first introduced^¶ in 1950.

 
Pin Connections

B8D & B8D/F	1	2	3	4	5	6	7	8
	a(2)	g1(2)	h	k(2)	k(1)	h	g1(1)	a(1)

 
Absolute Maximum Operating Conditions^¶

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	6.3	0.3	100	-1	6.5	6,500	5.4

Thanks to Frank Philipse for supplying the above PDF datasheet