The EF93 is a miniature screened pentode on a B7G base. It is a variable μ valve designed for HF use.

The thin glass tube envelope is 17 mm in diameter and, excluding the B7G base pins, is 47 mm tall.

References: Datasheet, ³⁰⁰² & ¹⁰⁴⁰. Type EF93 was first introduced^¶ in 1951.

 
Pin Connections

B7G	1	2	3	4	5	6	7
	g1	g3	h	h	a	g2	k

 
Absolute Maximum Operating Conditions^¶

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	6.3	0.3	250	100	-1	11	4.2	1.5M	4.4

Thanks to Frank Philipse for supplying the above PDF datasheet

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