Preamps
274B
Glass-enclosed eight-pin direct-heated full-wave rectifier tube, similar to 5U4G and 5Z3P, and can be used interchangeably.
Filament Heating
Voltage input....5V
If ...............2.5A
Restrict Rating
Peak anode reverse voltage............1550V
Peak anode current.........750mA
Recommended operating conditions
Anode power supply voltage 2500V
Impedance per arm 75
Load impedance 2000
Filter capacitor 4F
Rectification current 230mA