The 6BA6 is described by Brimar as a variable μ pentode for use at HF. Most probably as RF amplifiers in radio receivers.

The thin glass tube envelope is 18 mm in diameter and excluding the B7G base pins, is 47 mm long.

 
Pin Connections

B7G	1	2	3	4	5	6	7
	g1	g3-s	h	h	a	g2	k

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	gm
	6.3	0.3	250	100	-1	11	4.4

Thanks to Frank Philipse for supplying the above datasheet

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