The 6B8 was designed for signal and AGC detection and first audio amplifier stage in superhet receivers. The glass tubular version is a later development in a smaller envelope.

The grids are of wire and are supported on notched wire supports. This can be seen in the picture. The top cap can be seen connected to the inner of the wire grid supports.

The wide glass tube envelope is 28 mm in diameter and, excluding the IO base pins, is 74 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	m	h	a	a(d2)	a(d1)	g2	h	k	g1

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	6.3	0.3	250	125	-3	10	2.3	0.6M	1.33

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 04 July 2007 {find valves by name}