The 85 triode valve would be used in radio reception equipment. The diodes are for signal use and probably would be for AGC and AM signal detection. The triode would act as AGC amplifier or first audio amplifier, probably the latter.

The cathode tube runs vertically through both parts of the valve. The lower box forms the two diodes, each side being an independent anode. The upper black anode is formed with a cylindrical cavity that houses the cathode and grid.

The classic envelope is 35 mm in diameter and, excluding the UX6 base pins, is 97 mm tall.

 
Pin Connections

UX6	1	2	3	4	5	6	tc
	h	a	a(d2)	a(d1)	k	h	g

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	6.3	0.3	250	-20	8	7.5k	1.1

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 12 June 2007 {find valves by name}