GI-70BT (original box)

Description

The GI-70BT (ГИ-70БТ) triode is used for continuouswave or pulsed operation with anode modulation, as an oscillator and an amplifier. The triode is available in two variants differing in the type of cooling: the GI-7BT with a heat sink for forced air cooling and the GI-70BT with no heat sink for other systems of cooling.
Forced air cooling 24 м³/h.

Stamp of technical control department of the manufacturer “ ОТК “ 

GI – letters defining the type of tube: GI – generator pulse;
70 – the number of the ordinal number of the development of this type of tube;
B – a letter indicating the type of forced cooling: B – air;
T – design of the product.

Technical specifications:

• Heater voltage: 12.6 V
• Heater current: 1.8 A – 2.05 A
• Mutual conductance (at anode voltage 1.2 kV, grid voltage change by 1 V, anode current 150 mA): 20 mA – 26 mA
• Operating point (negative grid voltage at anode voltage 1.3 kV, anode current 150 mA): 12.5 V – 7.5 V
• Interelectrode capacitance: 10 pF – 12.2 pF
• Interelectrode output: 0.055 pF – 0.095 pF
• Interelectrode transfer: 4 pF – 5.2 pF
• Warm up time (at anode voltage 400 V): at most 90 s.
• Output power in CW operation (at anode voltage 1.05 kV, anode current 300 mA, wavelength 18.5 cm): at least 40 W
• Output power in pulsed operation (at peak anode voltage 9 kV, anode current 7.5 A, wave length 10 cm, 1/pulse duty factor 1 ,400 – 150, pulse duration 3 – 10 μs): at least 12 kW
• Output power over 650 hours of service: at least 32 W

 Limiting performance:

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

Operating time not less than 1000 hours.