Traveling Wave Tube (TWT)
Traveling wave tubes are velocity-modulated tubes that provide high gain amplification at microwave frequencies, essential for satellite communications and military radar. HTS 8540.89.00 covers these as other thermionic tubes due to their specialized electron interaction with electromagnetic waves.
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More Specific Codes
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If satellite communication equipment
Satellite ground station components under 8526 rather than separate tubes.
If military radar systems
Defense-specific tubes may classify under other electrical equipment for radar.
If laser auxiliary components
Certain high-power tubes for laser systems classified under optical/laser instruments.
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Import Tips & Compliance
• ITAR/EAR export licenses frequently required; verify classification before import planning
• Detailed helix structure and collector specifications needed for customs technical review
Related Products under HTS 8540.89.00
Magnetron Injection-Locked Tube
Phase-locked magnetron tubes for coherent microwave power combining in radar systems. Classified under HTS 8540.89.00 as specialized thermionic tubes with injection locking circuitry for phase control.
Klystron Power Amplifier Tube
Klystron tubes are specialized linear beam vacuum tubes used for amplification of microwave signals in high-power applications like radio transmitters and particle accelerators. Classified under HTS 8540.89.00 as other thermionic tubes due to their electron beam focusing mechanism in vacuum environment.
Xenon Flashtube Trigger Tube
High-voltage gas tubes triggering xenon flashtubes in high-intensity strobe lighting. HTS 8540.89.00 covers these as other gas-filled tubes initiating capacitive discharge through gas ionization.
Thyratron Gas-Filled Switching Tube
Thyratrons are gas-filled tubes containing low-pressure inert gas used for high-power switching and rectification in industrial applications. They qualify under HTS 8540.89.00 as other gas-filled tubes functioning through gas ionization triggered by cathode emission.
Ignitron Mercury Arc Rectifier Tube
Ignitrons are large mercury arc rectifier tubes used for high-current DC power conversion in industrial applications like aluminum smelting. HTS 8540.89.00 includes these mercury vapor-filled tubes operating via cathode-initiated arc discharge.
Photomultiplier Tube (PMT)
Photomultiplier tubes convert weak light signals into electrical pulses through electron multiplication across multiple dynodes. Classified under HTS 8540.89.00 as photocathode tubes designed for photon detection in scientific instruments.