The EF89 is a miniature RF voltage amplifier. Mullard describe the EF89 as a variable μ pentode for use as an RF or IF amplifier in FM/AM receivers and is designed to work with a tuned anode circuit.

The thin glass tube envelope is 19 mm in diameter and, excluding the B9A base pins, is 52 mm tall.

 
Pin Connections

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

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	6.3	0.2	250	100	-2	9	3	1M	3.6

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 10 June 2007 {find valves by name}