KT77 Vacuum tube Pentode

The vacuum tube KT77 is the A.F. beam pentode tube. The dimensions and connections of the tube are shown on Picture 1. The following data are for the KT77 tube manufactured by JJ Electronic.

Picture 1: KT77 Vacuum Tube Pentode Dimensions and Connections


Electrical Data:

Cathode heater:

> Heater Voltage: 6.3 V;
> Heater Current: 1.4 A;

Typical Characteristics:

> Plate Voltage: 250 V;
> Screen Voltage: 250 V;
> Grid Voltage: -15 V;
> Plate Current: 100 mA;
> Screen Current: 10 mA;
> Transconductance: 10.5 mA/V;
> Amplification Factor: 11.5;

Limiting Values:

> Plate Voltage: 800 V max;
> Plate Dissipation: 25 W max;
> Screen Voltage: 800 V max;
> Screen Dissipation: 6 W max;
> Cathode Current: 180 mA max;
> Negative DC Grid Voltage: -200 V max.

Capacitances:

> Cg1 = 16.5 pF;
> Ca = 9 pF;
> Cag1 = 1 pF.


Source: JJ Electronic.