This wonderful example of Mazda's late 1920s output arrived with the top covered in black bitumen type paint. The type number was found under the paint and etched into the glass.

The use of this valve was as an audio output device with an output of 640 mW.

See also AC/P for a later version of this valve.

The balloon envelope is 43 mm in diameter and, excluding the B5 base pins, is 95 mm tall.

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm
	4.0	1.0	200	-12	20.0	2650	3.75

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 16 April 2007 {find valves by name}