The 6F18 is a variable μ HF pentode for use in broadcast receivers at HF or IF.

The side view showing the anode occupies a large part of the envelope.

The thin glass tube envelope is 21 mm in diameter, and excluding the base pins is 48 mm tall.

 
Pin Connections

B9A	1	2	3	4	5	6	7	8	9
	k	g1	k	h	h	s	a	g2	g3

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm	μ
	6.3	0.2	175	100	-1.3	12.0	3.5	0.22M	4.4

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 29 August 2008 {find valves by name}