Sensibly equivalent¶ to:
The QP25 is a pre-war quiescent push-pull double pentode for battery operation. It was still listed as current production in 1951.
QPP valves operated in class B and for a 19 Volt peak to peak input signal the QP25 would deliver 1.1 Watt output at 5% distortion. See also QP230.
The box matched the style of the PA20 but was smaller measuring 40 mm square by 115 tall.
The type designation was on the top of the envelope.
The classic envelope is 30 mm in diameter, and excluding the MO base pins, is 70 mm tall.
References: Data-sheet & 1043. Type QP25 was first introduced in 1939.
Absolute Maximum Operating Conditions¶
Updated November 06, 2013. shape:classic construction:pinch type:double.pentode age:1930.1940 base:mo heater:2.0v pins:8 pin:1.f- pin:2.- pin:3.a pin:4.g2 pin:5.g1 pin:6.g1 pin:7.a pin:8.f+