This triode pentode was designed as a frequency changer for superhet receivers. The pentode has a high anode resistance and low mutual conductance, whilst the triode was designed for use as local oscillator.

This valve is essentially identical to the type AC/TP except for heater rating. A very robust Medium and Long Wave workhorse intended for simpler AC/DC superhets. Not intended for SW use.

The unusual feature is the B9 base.

The classic envelope is 43 mm in diameter and, excluding the B9 base pins, is 104 mm tall.

 
Pin Connections

B9	1	2	3	4	5	6	7	8	9	tc
	g2	a	g3	h	h	k	a(t)	g(t)	m	g1

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	26.0	0.2	250	200	-5	6.5	2.5	0.9M	0.7

Triode	Va	mAa
	150	1.5

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 12 June 2007 {find valves by name}