The PM24M was a replacement type made after WWII and is a directly heated output pentode. The valve would have been designed for the single ended audio stages in AC mains broadcast receivers and can produce 2.8 Watts.

The classic envelope is 47 mm in diameter and, excluding the B5 base pins, is 111 mm tall.

References: ¹⁰⁴⁰. Type PM24M was first introduced^¶ in 1932.

 
Pin Connections

B5	1	2	3	4	5
	a	g1	f-	f+	g2

 
Absolute Maximum Operating Conditions^¶

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	4.0	1.1	250	250	-17	30	5.6	43k	3.0

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