The Ever Ready K33A is equivalent to the Mullard type PM2B as Mullard made the Ever Ready valves of this period. As a push pull pair this type of triode could deliver 1.45 Watts audio output. The drive voltage would be about 40 Volts peak to peak.
The classic envelope is 43 mm in diameter and, excluding the B7 base pins, is 92 mm tall.
References: Datasheet & 1043. Type K33A was first introduced in 1935.
Absolute Maximum Operating Conditions¶
PDF scanned from an original document held by the museum
Updated December13, 2012. shape:classic construction:pinch type:triode age:1930.1940 base:b7 heater:2.0v pins:7 pin:1.g1(2) pin:2.g1(1) pin:3.a(1) pin:4.f pin:5.f pin:6.- pin:7.a(2)