The reason type 6C5 disappeared from the lists fairly early is that it was superseded by the 6J5 which had slightly superior ratings and characteristics but was, for all practical purposes, a direct replacement.

Most 6C5s were of the metal-envelope type whereas most 6J5s were 'GT/G' and therefore suitable for a wider range of applications. NB. Type 6SN7GT is two independent 6J5s in one envelope.

The thin metal tube envelope is 25 mm in diameter and, excluding the IO base pins, is 50 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8
	m	h	a	nc	g	nc	h	k

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	6.3	0.3	250	-8	8	10K	2

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 09 June 2007 {find valves by name}