GU-84B (original box)

The generator  tetrode GU-84B (ГУ-84Б rus.) is designed to operate in medium-power electronic devices with distributed amplification and amplification of a single-sideband signal with an output power of up to 1.5kW at a frequency of 75MHz, as well as a power amplifier at frequencies up to 250MHz with an output power of up to 1,2kW.

GU – a letter that determines the type of tube: GU – generator tubes with a generation frequency of 30 to 300 MHz;
84 – the number of the serial number of the development of this type of tube;
B – letter indicating the type of forced cooling: B – air.

Technical specifications:

• Heating voltage: 27V
• Glow current 3.4-4.0A
• Bias voltage negative (at Ua=750V, Uc2=375V, Ia=2000mA): 10 – 50V
• Turn-off voltage on the first grid (at Ua=2000V, Uc2=375V, Ia=20mA): no more than 150V
• Zero anode current (at Ua=250V, Uc2=375V, Uc1=0V): 3.5-6A
• Reverse current of the first grid (at Ua=1000V, Uc2=375V, Ia=2000mA): no more than 80uA
• Second grid current (at Ua=750V, Uc2=375V, Ia=2000mA): 25 ± 60mA
• Slope (at Ua=750V, Uc2=375V, Ia=): 44 – 72mA/V
• Output power :
  – in class AB mode on a frequency of 0.1 – 1MHz, not less than 1.5kW
  – in class B mode at a frequency of 250MHz, not more than 1.2kW

Limiting performance:

• Heating voltage 25.6 – 28.4V
• Anode voltage:
  – constant 2.2kV
  – instantaneous value 4.25kV
• Voltage of the second grid 400V
• First grid voltage is negative (absolute value) 150V
• Input voltage (peak value) 150V
• Voltage cathode-heater (absolute value) 100V
• Cathode current:
  – constant component 2A
  – instantaneous value 6A
• Ambient operating temperature range from -10 to +70°С

Operating time not less than: 2000 hours.