<< 205D 205D/n Vacuum Tube



Classification- Globe-type bulb of glass, a white ceramic base with four-prong bayonet golden pins, oxide coated filamentary, solid plate or mesh plate triode.

Application -Audio amplifier Class A Service, Radio Amplifier Class B Service. Oscillater Class C Service.

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* 4.5V
Nominal filament current 1.2A
Plate voltage 300V
Grid voltage** -24V
Plate current 15mA
Amplification factor 7.3
Grid current 0.05 A
Plate resistance 5.0 kohms

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

Fig 3

Limiting Operation Conditions for Safe Nor simultaneous ratings
Maximum plate voltage 400 volts
Maximum plate dissipation 14 watts
Maximum plate current 50mA