Sensibly equivalent¶ to:
The N42 is an audio output pentode with a maximum anode dissipation of 8 W. The N42 was introduced in 1935 but was replaced by the KT42 beam tetrode in 1937.
The heater is the pre-war british standard of 4.0 Volts at 1 Amp, and the N42 was designed for receiver output stages following a detector and triode voltage amplifier.
The envelope is etched on one side and has the paper Marconi label on the other.
The classic envelope is 44 mm in diameter, and excluding the B7 base pins is 97 mm tall.
References: Datasheet & 1043. Type N42 was first introduced in 1935.
Absolute Maximum Operating Conditions¶
Updated December13, 2012. shape:classic construction:pinch type:pentode age:1930.1940 base:b7 heater:4.0v pins:7 pin:1.- pin:2.g1 pin:3.g2 pin:4.h pin:5.h pin:6.k pin:7.a