The DH63 is a double diode triode 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. This is a miniature glass tubular version of this valve, we also have the older version with the classic glass envelope.

Sadly our exhibit is missing its metal top cap.

The wide glass envelope is 27 mm in diameter and, excluding the IO base pins, is 80 mm tall.

References: Datasheet. Type DH63 was first introduced^¶ in 1937.

 
Pin Connections

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

 
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 PDF datasheet

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