PM254 Azide Triode

A 3 watt power triode valve for audio output. 4 volt, 180 mA filament. Anode voltage 150 V, grid bias -22.5 V, mu 4.2 ra 2000. B4 base. Cost 16/6 in 1931, equivalent to £128.00 using average wages! PM252 and PM256 are 2 and 6 volt filament equvalents. The PM256A was a slightly inferior valve (lower gain and anode voltage) but had 6 watts anode dissipation.

PDF Data Sheets PM252, PM254, PM256, PM256A