The 41MH triode dates from 1931. The valve has external metalising and this screening indicates an RF use.

See also 41MH for the original balloon envelope version.

The classic envelope is 46 mm in diameter and, excluding the B5 base pins, is 110 mm tall.

 
Pin Connections

B5	1	2	3	4	5
	a	g1	h	h	k,

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	4.0	1.0	200	-1.5	3.2	18,000	4.0

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 02 December 2007 {find valves by name}