Mullard, in 1949, describe the ECC33 as a high slope, low impedance double triode with low heater consumption, primarily intended for use in flip-flop, scaling and computer circuits. The electrode assembly is considerably smaller than other double triodes of the period.

The wide glass tube envelope is 30 mm in diameter and, excluding the IO base pins, is 67 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8
	g(2)	a(2)	k(2)	g(1)	a(1)	k(1)	h	h

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	6.3	0.4	250	-4	9	9,700	3.6

Thanks to Frank Philipse for supplying the above datasheet

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