Characteristics:
Mesh Plate
Hook Filament
Ceramic Base
Gold Pins
Classification-Dome-type or Aubergine-type bulb of glass, a white ceramic base with four-prong bayonet gold pins , oxide coated filamentary, solid plate, mesh plate, cabon plate triode.
Application-Audio frequency amplifier where power outputs of approximately 8.5watts 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 and 3.
Nominal operating conditions and parameters
Filament voltage…………………………………………………………5 V* or 2.5V*
Nominal filament current………………………………………………1.2A or 2.5A
Plate voltage…………………………………………………………………300V
Grid voltage…………………………………………………………………－58 V**
Plate current…………………………………………………………………60 mA
Amplification factor…………………………………………………………3.85
Grid to plate transconductance …………………………………………5700 micromhos
Grid current………………………………………………………………… 0.05 μA
Plate resistance………………………………………………………………700 ohms
*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 platter returns are connected to the negative end of the filament.
Characteristics-Average characteristics
Figure 4. shown typical curves of plate currents of grid voltage for several values of plate voltages. It is alternating-current filament supply.
Fig.4
Limiting Operation Conditions for Safe Nor-nor simultaneous ratings
Maximum plate voltage…………………………………………………………450 volts
Maximum plate dissipation………………………………………………………40 watts
Maximum plate current of average tube for fixed gird bias…………………….70mA
Maximum plate current of manually adjusted gird or self-biasing circuit………100mA
Pre-Amplifiers
