Eimac 3-400Z (8163) Power Amplifier Tube Tested Full Output S/N 921740 date code 7003

Eimac 3-400Z (8163) Power Amplifier Tube Tested Full Output S/N 921740 date code 7003

 I tested this 3-400Z, in an Ameritron AL-80 Amplifier and it is performing at full output.

It also comes with the anode heat sync cap as pictured.

 This "low profile" 3-400Z is perfect for the older Henry amplifiers as they fit where the 3-500Z will not

date code 7003 indicates it was manufactured in the 3rd week of 1970 at Eimac’s San Carlos, California facility. Tubes of this era are among the best made.

• Anode Material: Tantalum (requires "red heat" for gas absorption).
• Base: 5-Pin Special (fits Eimac SK-410 or similar sockets).
• Cooling: Radiation and forced air (vertical mounting preferred).
• Envelope: Hard glass (Nonex).

• Filament Voltage: 5.0 Volts (AC or DC).
• Filament Current: 14.5 Amps (± 1.0 A).
• Amplification Factor (
  

  Technical Specifications

  • Type: High-Mu Power Triode (Zero-Bias).
  • Filament: 5.0V @ 14.5 Amps.
  • Max Plate Voltage: 3500 VDC.
  • Max Plate Current: 250 mA.
  • Plate Dissipation: 400 Watts.
  • Amplification Factor (
     

• Interchangeability: They are pin-for-pin compatible.
• Drive Power: The 3-400Z is slightly easier to drive than a 3-500Z.
• Heat: The tantalum anode in your Amperex must glow dull red during operation to maintain its vacuum integrity (the "getter" action).