Type 6J7 is a contemporary of the Magic Three and almost as ubiquitous. Although originally designed as a detector its linear characteristic and good internal shielding (cf. 6Q7G) made it a natural choice for audio.

It was for two decades the international standard valve for audio amplifier input stages and audio systems generally. The Mullard-Philips type EF37A, for many years the standard British low-noise audio pentode, is really a 6J7G under another name.

The classic envelope is 36 mm in diameter and, excluding the IO base pins, is 99 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	m	h	a	g2	g3	-	h	k	g1

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	6.3	0.3	250	100	-3	2.0	0.5	1.5M	1.25

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 09 February 2008 {find valves by name}