The Pen220 is of classic Mazda shape and design of the later 1930s.

The Pen220 is a battery output pentode for use in the audio output stage of domestic receivers. The Pen220A had a higher anode current and produced 1.1 Watts of audio, again with 7% distortion.

The filament is a pair of inverted V's. At the top of the envelope can be seen the spiral springs used to tension the filament. The valve has three wire grids and an oval cylinder anode.

The balloon envelope is 43 mm in diameter and, excluding the B5 base pins, is 91 mm tall.

 
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	gm	Pout	D
	2.0	0.2	150	150	-4.9	9	1.6	2.2	0.6W	7%

Thanks to Frank Philipse for supplying the above datasheet

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