This DAC32 exhibit is covered in the Mullard red external metalisation. The DAC32 is a dry battery diode triode that was designed, after WWII, for AM broadcast radio reception. Mullard describe this valve as a medium gain triode for use as an AF voltage amplifier combined with a single diode for signal or AVC (AGC) rectification.

The filament power is very low and consequently the valve is rated for a very low current.

See also DAC32 for a clear envelope version.

The wide glass tube envelope is 30 mm in diameter and excluding the IO base pins it is 86 mm tall.

References: Datasheet, ¹⁰⁴⁰ & ¹⁰⁴³.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	m	f+	a	-	a(d)	-	f-	-	g1

 
Absolute Maximum Operating Conditions^¶

Triode	Vh	Ah	Va	mAa	ra	gm
	1.4	0.05	90	0.15	240k	0.275

Thanks to Frank Philipse for supplying the above PDF datasheet

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