Classification-Dome-type bulb of glass, a white ceramic base with four-prong bayonet gold pins, oxide coated filamentary, mesh plate triode.
Application-Audio frequency amplifier where power outputs of approximately 10 watts or less is required at relatively low plate voltages.
Dimensions-Dimensions, outline diagrams of the tube and bases, and the arrangement of electrode connections to the base terminals are shown in Figures 1,2.

Nominal operating conditions and parameters
Filament voltage……………………4.0 V or5.0 V*
Nominal filament current……………2 A or 1.6 A
Plate voltage…………………………400 V
Grid voltage…………………………–30V**
Plate current…………………………62.5 mA
Impedance***…………………………1265 ohms
Amplification factor***………………9.5
Mutual Conductance***………………7.5 mA/V
Grid current……………………………0.05μA

*Alternating-current filament supply or Direct-current filament supply.
**Alternating-current filament supply is used. The grid and plate returns should be connected to a center tap on the secondary of the filament transformer.
***Direct-current filament supply is used. The grid and plate returns areconnected to the negative end of the filament.
*Measured at Va=100;Vg=0

Characteristics-Average characteristics

Figure 3.shown typical curves of plate currents as a function of grid voltage for several values of plate voltages. It is alternating-current filament supply.

Limiting Operation Conditions for Safe Operation-nor simultaneous ratings
Maximum plate voltage …………………………………………………500 volts
Maximum plate dissipation …………………………………………….30 watts

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