The PCL84 is a television valve. The pentode in this valve was designed as a video rather than audio output stage. The triode was general purpose.

The thin glass tube envelope is 19 mm in diameter, and excluding the B9A base pins, is 60 mm tall.

References: Datasheet & ¹⁰⁴⁰

 
Pin Connections

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

 
Absolute Maximum Operating Conditions^¶

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	15.0	0.3	220	220	-3.4	18.0	3.1	150,000	10

Thanks to Frank Philipse for supplying the above PDF datasheet

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