3CX2500A3 / 8161 Triode Tube

The Penta Labs 3CX2500A3 / 8161 Triode tube for sale is part of the family of medium-mu triodes are renowned for their robust performance and reliability in broadcast and industrial heating applications. These forced-air-cooled tubes offer high power output and are available in several configurations to suit diverse needs.   

Key Features:

• Medium-Mu Triode: Provides efficient amplification with moderate drive power.
• Rugged Construction: Built for long life and dependable operation in demanding environments.
• Forced-Air Cooling: Enables high power operation through efficient heat dissipation.   
• Versatile Configurations:
  • 3CX2500A3: Coaxial base for standard socket mounting.
  • 3CX2500F3: Flexible leads on all terminals for versatile connection.
  • 3CX2500H3: Flexible filament leads and a grid flange for mounting, offering enhanced stability.

Applications:

• High-frequency broadcast transmitters
• Industrial RF heating equipment   
• Audio Amplification (Push-Pull)

Specifications (Typical Values):

• Filament Voltage: 7.5 V ± 0.37 V
• Filament Current (at 7.0V): 51.5 A
• Direct Interelectrode Capacitances (Grounded Cathode):
  • Cin: 35 pF   
  • Cout: 0.9 pF
  • Cgp: 20 pF
• Amplification Factor (average): 22
• Maximum Frequency of Operation:
  • 3CX2500A3: 110 MHz
  • 3CX2500F3/H3: 75 MHz   
• Maximum Plate Voltage: 6.0 kV
• Maximum Plate Current: 2.5 A
• Maximum Plate Dissipation: 4.0 kW   
• Maximum Grid Dissipation: 150 W   
• Typical Operation (Class C below 30 MHz): See Datasheet for specific operating parameters for different applications (RF Amplifier/Oscillator, Plate-Modulated RF Amplifier, Audio Amplifier/Modulator).

Mechanical Characteristics:

• Overall Dimensions:
  • 3CX2500A3: Length: 9.0 in (227 mm), Diameter: 4.15 in (105 mm)
  • 3CX2500F3/H3: Length: 15.44 in (468 mm), Diameter: 4.15 in (105 mm) / 4.25 in (108 mm)

• Weight (approx.): 7 lb (2.9 kg)

• Operating Position: Vertical, base up or down

• Maximum Operating Temperatures:
  • Ceramic/Metal Seals & Envelope: 250°C
  • Filament Leads at Tube Base: 150°C   

Why Choose the Penta 3CX2500 Family?

• Industry Standard: A widely recognized and trusted choice for high-power applications.
• High Performance: Delivers substantial RF power with efficient operation.
• Versatile Options: Available in different configurations to meet specific design requirements.
• Reliable Operation: Robust design ensures long life and consistent performance.

Note: For detailed specifications, operating characteristics, and application-specific data, please refer to the official datasheet provided by Penta Laboratories upon request. This is a replacement for the 8161R tube sold by Richardson Electronics under the Eimac brand.