RF amplifiers have been developed for use in the Facility for Rare Isotope Beams (FRIB) linear accelerator facility, which is currently under construction at Michigan State University. The development process has included the design, building, and testing of individual components, which together make a full-scale prototype suitable for testing purposes. These full-scale prototypes can be used in Superconducting Radio Frequency (SRF) resonator cavity conditioning, low energy linear accelerators such as the ReA3 re-accelerator, or simply bench tested.The design of an amplifier suited for driving a linear accelerator cavity is different from an amplifier designed for more conventional applications such as FM or UHF broadcasting in several ways. Most importantly, amplifiers used in linear accelerator cavity applications are repetitively subject to full reflection load conditions which can destroy the amplifier in seconds. This necessitates the use of a circulator in every amplifier. Accelerator cavities also require power levels in the 2 - 8 kW range, which is significantly above what a single solid state power transistor can handle.Amplifier components discussed include pallet amplifiers, along with low pass filter circuits, circulators, and power combiner blocks. Together, these four components can be used to create an amplifier system which reaches the power levels required, can tolerate a full reflection load through all phases, and meets the longevity and cost requirements set forth by the FRIB project.
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