GMI-83V

TETRODE

The GMI-83V tetrode is used as a power amplifier in pulse modulator circuits

GENERAL
Cathode: indirectly heated, oxide-coated.
Envelope: glass, with base.
Height: at most 146.5 mm.
Diameter: at most 65 mm.
Mass: at most 300 g

1 - grid 1; 2 - cathode and heater; 3 - heater; 4 - grid 2; A - anode-top cap

BASIC DATA Electrical Parameters
Heater voltage, V	25
Heater current, A	2-2.5
Peak anode current, A, at least	15
Peak grid 2 current and peak grid 1 current (at anode voltage 20 kV, grid 2 voltages 1.25 kV, grid 1 voltage -800V, peak grid 1 excess voltage 250 V), A, at least	0
Cutoff voltage, V	300-700
Interelectrode capacitance, pF:
input	30-35
output	5-11
transfer, at most	1
Electric strength (at anode voltage 20 kV, grid 2 voltage 1.25 kV, grid 1 voltage -800 V, peak grid 1 excess voltage 250 V, pulse duration 2 µs, pulse frequency 500 pulses/s), number of sparkings, at most	25
Electrical parameters over 500 h of service:
peak anode current, A, at least	13
electric strength, number of sparkings:
for 80 % of tubes, at most	20
for 20 % of tubes, at most	50

Limit Operating Values
Heater voltage, V	22.5-27.5
Anode voltage, kV	18
Grid 1 voltage, kV	-1
Grid 2 voltage, kV	1.25
Peak grid 1 excess voltage, V	250
Peak cathode current, A	25
Dissipation, W:
anode	60
grid 2	9
grid 1	3
Pulse duration, µs	5
Warm up time, s, at least	180
Temperature at envelope and seals, °C	200

Averaged Peak Anode-Grid Characteristic Curves:
U_f = 25V; U_g2 = 1kV; U_g1 = -800V; U_{g1 imp} = 250V;
_____ anode;
_ _ _ grid-anode

Averaged Peak Anode-Grid Characteristic Curves:
U_f = 25V; U_g2 = 1.25kV; U_g1 = -800V; U_{g1 imp} = 250V;
_____ anode;
_ _ _ grid-anode

Averaged Peak Anode-Grid Characteristic Curves:
U_f = 25V; U_g2 = 1.25kV; U_g1 = -800V

Characteristic Curves of Grid 1 Cutoff Voltage versus Anode Voltage