The P220 triode from Mazda is a low wattage audio output valve for battery radio receivers. The load impedance is 10,000 Ohms and the power output is given as 180 mW.

The dome of the envelope carries the identification etched into the glass.

The balloon envelope is 45 mm in diameter, and excluding the B4 base pins is 93 mm tall.

 
Pin Connections

B4	1	2	3	4
	a	g1	f	f

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	gm
	2.0	0.2	150	-7.0	5.5	3.4

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 10 February 2008 {find valves by name}