The PL36 was designed as a line timebase output valve for television receivers.

The design dates to the 1950s, when sets were black and white and screen sizes of 14 - 17 inches diagonal were common. The PL36 was designed for driving the line deflection on 90° deflection angle tubes.

From a Mullard Press release in February 1956: The Mullard PL36 is an output pentode primarily designed for the line timebases of television receivers using picture tubes with a deflection angle of 90°, and 16 kV EHT. The new valve is octal based, and has a 25 V, 0.3 A heater, suitable for series operation.

The maximum positive peak voltage on the anode is 7 kV and the screen dissipation is up to 5 W.

The wide glass tube envelope is 28 mm in diameter and, excluding the IO base pins, is 90 mm tall.

References: Datasheet & ¹⁰⁴⁰. Type PL36 was first introduced^¶ in 1954.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	-	h	-	g2	g1	-	h	k,g3	a

 
Absolute Maximum Operating Conditions^¶

Pentode	Vh	Ah	Va	Vs	mAa	mAs	Pdiss
	25	0.3	170	170	100	8.0	10.0W

Thanks to Frank Philipse for supplying the above PDF datasheet

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