Russian HF pentode tube 6K3. Equivalent to the 6SK7.
Name: 6K3;
Type: HF pentode;
Application: HF voltage amplification;
Cathode type: oxide,indirect heating;
Envelope: metal;
Mass, g: 45;
Filament voltage, V: 6,3;
Filament current, A: 0,275-0,325;
Anode voltage, V: 250;
Anode current ,A: 0,007-0,012;
Anode power, W: 4,4;
Grid1 voltage, V: minus 3;
Grid2 voltage, V: 100;
Grid3 voltage, V: 0;
Steepness, mA/V: 1,6-2,4;
Microphnic noise, mV: 120;
Socket type: rsh5-1.