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. 6Q7GT) 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. In this exhibit we see the Mullard 6J7. The central spigot of the IO base has been broken off.

The thin metal tube envelope is 25 mm in diameter, and excluding the IO base pins, is 60 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	-2	1.0	0.25	1.5M	1.23

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 06 September 2008 {find valves by name}