7J12S

Technical specifications:

• Filament voltage: 7.35 ± 0.5V
• Filament current: 425mA
• Anode voltage nominal (constant): 250V
• Anode voltage limit (constant): 250V
• Anode current: 5.5 ± 1.5mA
• Grid voltage of the first nominal (constant): -3V
• Reverse grid current of the first: 0.5μA
• Grid voltage second nominal (constant): 135V
• Grid voltage second limit (constant): 180V
• Grid current second: 1.05 ± 0.55mA
• Grid voltage of the third nominal (constant): 0V
• Limit voltage between cathode and heater: 150V
• Leakage current between cathode and heater: 20μA
• Anode insulation resistance: 20MOhm
• Grid insulation resistance of the first: 20MOhm
• Slope: 1.85 ± 0.25mA/V
• Slope at 380 mA filament current: 1.45mA/V
• Maximum power dissipated at the anode: 1.9W
• The highest power dissipated on the second grid: 0.4W
• Output power (approx. 1): 0.4W
• Nonlinear distortion coefficient: no more than 14%
• Internal resistance 500kOhm
• Input capacitance: 5.8 ± 1.2pF
• Output capacitance: 12.5 ± 3.5pF
• Capacitance through: 0.03pF
• Characteristic steepness: not less than 1.3mA/V
• Reverse current of the grid of the first: no more than 1.5μA

The minimum operating time is not less than 6000 hours.