Classification-column type bulb of glass, copper ceramic base with four gold pins , oxide coated filamentary, carbon plate, triode.
Application-Audio power amplifier A-F, R-F of class B or R-F of class C.
Dimensions-Dimensions, outline diagrams of the tube and bases, and the arrangement of electrode connections to the base terminals are shown in Figures 1 and 2

Nominal operating conditions and parameters
Filament voltage……………………………………………………………10.0V
Nominal filament current……………………………………………………0.6 A
Plate voltage…………………………………………………………………900 V
Grid voltage…………………………………………………………………20 V
Plate current………………………………………………………………… 110 mA

Suggest operating conditions and parameters A-F of Class B power amplifier ( two tube )

Plate voltage 1250 1500 1500 V
Ia(max. sig. per tube ) 210 Ma
Pa (in ) ( max. sig. per tube ) 315 W
Pa( per tube) 125 W
Grid voltage -16 V
Ug~ ( pk ) 235 280 V
Ia (O) 148 84 Ma
Ia ( max. sig. ) 500 600 Ma
Pd 6 7 W
Load resistance ( a-a ) 6.7 8.2 kohms
Pout( max. sig. ) 300 370

R-F of classB power amplifier of push-pull

Plate current 800 1000 1000 1250 V
Plate voltage -125 -170 -175 -225 V
Grid voltage 4.5 4.6 4.6 6.6 kohms
Load resistance 80 70 40 40 mA
Signal voltage(pk) 177 240 V
Output powe 40 75 75 115 W