The DAF96 is a dry battery valve and exhibits very low filament consumption. This is one of the last generation of dry battery valves, and dates to the 1950s. It was designed for detector and first audio stage use and can be found in the small suitcase portable sets of the period.

The side view shows the oval anode and the small volume occupied by the actual electrode assembly. At the top of the envelope the filament is attached to a coiled spring to provide tension.

Seen in close-up the grids can be seen inside the anode. The suppressor grid can be easily identified as the wide pitch helix just inside the anode. The filament appears as a thin black line running horizontally in the centre of the picture. Even under a magnifying glass the tungsten wire that the oxide coating is fixed to is difficult to see as it is very fine.

The thin glass tube envelope is 17 mm in diameter and, excluding the B7G base pins, is 48 mm tall.

 
Pin Connections

B7G	1	2	3	4	5	6	7
	f-	-	a(d)	g2	a	g1	f+

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	gm
	1.4	0.025	67.5	67.5	-1.5	0.17	0.055	0.17

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 05 July 2007 {find valves by name}