The 6Q7GTY is clearly also marked CV589. As the GT stands for glass tubular the Y suffix denotes better RF performance from the base.

This double diode triode was designed for receiver audio use.

The diodes would be for signal and AGC rectification and the triode would act as AGC amplifier or first audio amplifier.

The wide glass tube envelope is 27 mm in diameter and, excluding the IO base pins, is 72 mm tall.

 
Pin Connections

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

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	6.3	0.3	250	-3	1	58k	1.2

Thanks to Frank Philipse for supplying the above datasheet

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