GI-7B (original box)

The GI-7B (ГИ-7Б rus.) microwave triode operates as an oscillator and an amplifier in continuous-wave or pulsed mode with anode modulation in the centimetric and decimetric wavelength ranges. Cathode: indirectly heated, oxide-coated. Envelope: metal-ceramic. Cooling: forced air.
Forced air cooling 24 м³/h.

Stamp of technical control department of the manufacturer “ ОТК “ 

GI – generator pulse;
7 – the number of the serial number of the development of this type of tube;
B – a letter indicating the type of forced cooling: B – air.

Technical specifications:

• Heater voltage: 12.6V
• Heater current: 1.8A – 2.05A
• Mutual conductance (at anode voltage 1.2kV, grid voltage change by 1V, anode current 150 mA): 20mA – 26mA
• Operating point (negative grid voltage at anode voltage 1.3 kV, anode current 150 mA): 12.5V – 7.5V
• Interelectrode capacitance: 10pF – 12.2pF
• Interelectrode output: 0.055pF – 0.095pF
• Interelectrode transfer: 4pF – 5.2pF
• Warm up time (at anode voltage 400V): at most 90 s.
• Output power in CW operation (at anode voltage 1.05kV, anode current 300mA, wavelength 18.5 cm): at least 30W
• Output power in pulsed operation (at peak anode voltage 9kV, anode current 7.5A, wave length 10 cm, 1/pulse duty factor 1 ,400 – 150, pulse duration 3μs – 10μs): at least 11kW
• Output power over 650 hours of service: at least 24W

 Limiting performance:

• Heater voltage: 12V – 13.2V
• Anode voltage:
• in pulsed operation 9kV
• instantaneous value in CW operation: 5kV
• DC in continuous operation: 2.5kV
• DC with cold cathode: 3kV
• Grid voltage:
• instantaneous value in continuous operation -400V to 80V
• in pulsed operation: -900V to 600V
• Cathode current:
• r.m.s. value 0.6A
• DC component under conditions of class В without modulation: 0.4A
• instantaneous value under conditions of class В without modulation: 1.25A
• Anode current (DC component in pulsed operation): 7.5A
• Dissipation anode: 350W
• Dissipation grid: 7W

Operating time not less than 1000 hours.