4 PCS 6J4 ( 6AC7/6AJ7 ) 
NEW VACUUM TUBE METAL BASE USSR

Specifications and electrical parameters of the lamp 6J4:

Rated electrical data:

Tension of heat, V 6,3

Anode voltage, V 300

Voltage on the second grid, V 150

Voltage on the third grid, V 0

Resistance in the cathode circuit for automatic bias, Ohm 160

Filament current, mA 450 ± 25

Current in the anode circuit, mA 10.25 ± 2.25

Current in the circuit of the second grid, mA 2.2 ± 1.0

The steepness of the characteristics, mA / V 9.0 ± 2.0

Internal resistance, mOhm 3

Input impedance at frequencies 45-60 MHz, ohms about 2600

Maximum permissible electrical quantities:

• The highest filament voltage, V 7

• The lowest voltage on the heat, V 5.7

• The greatest tension on the anode, V 330

• The highest voltage on the second grid, V 165

• Maximum power dissipated at the anode, W 3.3

• Maximum power dissipated on the second grid, W 0.45

• The greatest constant voltage between the cathode and the heater, V 100

• Maximum leakage current between the cathode and the heater, µA 20