Classification-Aubengine-type bulb of glass, a four-prong bayonet pin tube,oxide coated filamentary,mesh plate , canbon plate triode.
Application-Audio frequency amplifier where power outputs of approximately 4.5 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 and 2.

Nominal operating conditions and parameters

Filament voltage……………………....4.0 V*
Nominal filament current……………. 1A
Plate voltage…………………………. 300 V
Grid voltage………………………….. –45V**
Plate current…………………………...50 mA
Impedance…………………………….830 ohms
Amplification factor………………......5.0
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.

Characteristics-Average characteristics

Figure 4.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 ………………………………………………….300 volts
Maximum plate dissipation ………………………………………………15 watts

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