GU-44A

TETRODE

The GU-44A tetrode is used as a RF power in amplifier short-wave transmitters

GENERAL
Cathode: directly heated, carbonized thoriated tungsten
Envelope: glass-to-metal
Cooling: forced (water for anode, air for envelope,
stem and seals).
Height: at most 506 mm.
Diameter: at most 182 mm.
Mass: almost 13kg

OPERATING ENVIRONMENTAL CONDITIONS
Ambient temperature, °C	-10 to +55
Relative humidity at up to +25 °C, %	98

BASIC DATA Electrical Parameters
Filament voltage, V	12.6
Filament current, A	170-200
Mutual conductance (at anode voltage 1.5 kV, grid 2 voltage 1 kV, anode currents 8 and 12A),mA/V	55-75
Gain coefficient (grid 1 - grid 2) (at anode voltage 1.5 kV, grid 2 voltages 1 and 1.4 kV, anode current 8 A)	4.2-6.2
Interelectrode capacitance, pF:
input, at most	300
output, at most	55
transfer, at most	4
Negative cutoff voltage (at anode voltage 10 kV, grid 2 voltage 2 kV, anode current 0.5 A), V, at most	700

Limit Operating Values
Filament voltage, V	12-13
Anode voltage (DC), kV	12
Negative grid 1 voltage, kV	1.5
Grid 2 voltage (DC), kV	2
Filament starting current, A	300
Dissipation, kW:
anode	50
grid 2	3.2
grid 1	1.2
Operating frequency (at output power 70kW), MHz	32
Temperature at envelope, stem and seals, °C	150

Averaged Characteristic Curves:
U_f = 12.6V; U_g2 = 1.5kV;
_____ anode;
_ _ _ grid 2-anode;
— x — P_{a max} (GU-44A);
— . — P_{a max} (GU-44B)

Averaged Characteristic Curves:
U_f = 12.6V; U_g2 = 2kV;
_____ anode;
_ _ _ grid 2-anode;
— x — P_{a max} (GU-44A);
— . — P_{a max} (GU-44B)

Averaged Characteristic Curves:
U_f = 12.6V; U_g2 = 1.5kV;
_____ anode-grid;
— . — grid 1;
_ _ _ grid 2

Averaged Characteristic Curves:
U_f = 12.6V; U_g2 = 2kV;
_____ anode-grid;
_ . _ grid1;
_ _ _ grid 2