klystron
High-power microwave vacuum-tube amplifier. Generates the RF energy that accelerates electrons through the linac waveguide. Used on dual-energy and higher-power linacs (TrueBeam, Versa HD, Clinac iX dual-energy variants); single-energy lower-power configurations sometimes use the simpler magnetron instead.
Why it matters to buyers: Finite lifespan, scheduled-wear consumable. The most expensive routine wear item on a Clinac iX / TrueBeam-class linac. Filament-current drop is the typical end-of-life signal — interlocks trip before catastrophic failure if monitoring is in place. Lead time for klystron replacement is non-trivial; sites without a parts agreement can wait days to weeks.
Why it matters to engineers: Never bypass klystron interlocks. Late-stage klystron arcing risks collateral damage to the waveguide, circulator, and bend magnet — a single failed klystron can become a multi-component event. Schedule replacement based on usage data, not calendar age.
Related
- magnetron (alternative RF source on lower-power configurations)
- thyratron (drives the klystron pulse)
- waveguide
- Clinac iX Klystron part
- Linear Accelerator
- Varian Clinac iX
- Varian TrueBeam
- AAPM TG-142
- Clinac iX Field Guide
- TrueBeam Field Guide
- Linac Decommissioning