GU-74B

The GU-74B (4CX800A, ГУ-74Б rus.) Svetlana tetrode is used in wide-band non-tunable amplifiers and for single-sideband power amplification in stationary and mobile RF equipment. It is useful at full ratings through 250MHz. GU74B (4CX800A) Ceramic Power Tetrodes are high performance ceramic/metal tetrodes with a plate dissipation rating of 800 watts.The performance characteristics of the 4CX800A allow its use as a high gain grid-driven RF amplifier or as used in grounded grid service.

Stamp of technical control department of the manufacturer “ ОТК “ 

GU – generator tubes with a generation frequency from 30 to 300MHz
74 – the number of the serial number of the development of this type of tube
B – letter indicating the type of forced cooling

Technical specifications:

• Cathode type: oxide, indirect heating
• Application field: power amplification in broadcasting and SSB equipment
• Brief application: amplification
• Envelope: metal-ceramic
• Cooling method: forced air
• Forced air cooling of at least 35m³/h.
• Dimensions: 90 x 71mm 
• Filament voltage: 12.6V 
• Filament current: 3.3A … 3.9A
• Mutual conductance: 26 to 38mA/V 
• Output power: 0.6kW
• Maximum anode voltage: 2kV/4kV in peak
• Maximum operating frequency: 150MHz

Durability is not less than 2000 hours.