The S4VA is a screen grid or tetrode valve. It was available in both clear and metalised versions. The S4VB had a lower anode AC resistance. Both versions were developments of the 1929 S4V.

The S4VA and S4VB were listed in the 1933-4 catalogue for re-valving use.

The bakelite scrw down top cap. The metal cap originated with the Octal valves in the mid 1930s.

The balloon envelope is 48 mm in diameter and, excluding the B5 base pins, is 130 mm tall.

References: 1931 datasheet, ⁴⁰²⁴ & ¹⁰⁴³. Type S4VA was first introduced^¶ in 1930.

 
Pin Connections

B5	1	2	3	4	5	tc
	g2	g1	h	h	k	a

 
Absolute Maximum Operating Conditions^¶

Tetrode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm	μ
	4.0	1.0	200	80	-1	3.4	1.2	0.5M	2.0	1,000

Thanks to Andy Cowley for supplying the above PDF datasheet

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