J20P high frequency pentode with short characteristic, with cathode grid.
Purpose: broadband high frequency voltage amplification.
Decoration - glass miniature
Weight 20 g
Basic data
Filament voltage 6.3 ± 0.6 V
Filament current 450 ± 40 mA
Anode voltage nominal (constant) 150 V
Anode voltage limit (note 1) (constant) 200 V
Anode current 16.5 ± 4 mA
The voltage of the cathode (first) grid nominal (constant) 6 V
The voltage of the cathode (first) grid is the largest (constant) 6.6 V
The voltage of the cathode (first) grid is the smallest (constant) 5.4 V
Cathode grid current (first) 35 +3 -10 mA
Voltage of the control (second) grid Minus 20 V
Reverse current of the control (second) grid 0.2 μA
Voltage shielding (third) mesh rated
(continuous) 150 V
Screening voltage (third) grid limit
(continuous) 200 V
Shielding (third) grid current 6 mA
Power dissipated by the anode, limit 4 W
Power dissipated by the grid first, limit 0.25 W
Power dissipated by the third grid, limit 1.2 W
Voltage between the cathode and the heater limit
(continuous) (approx. 2) 150 V
Slope 16.5 ± 3.5 mA/V
Internal resistance 90 kΩ
Equivalent tube noise resistance 0.35 kOhm
Input impedance at 60 MHz 6 kOhm
Cathode resistance for automatic bias 70 Ω
Resistance in the grid circuit of the second limit 1 MΩ
Input capacitance 9.0 ± 1 pF
Output capacitance 2.45 ± 0.3 pF
Capacitance through 0.04 pF
Capacitance cathode - heater 7 pF