A multi-frequency klystron has an electron gun which generates a beam, a circuit of bunch-align-collect (BAC) tuned cavities that bunch the beam and amplify an RF signal, a collector where the beam is collected and dumped, and a standard output cavity and waveguide coupled to a window to output RF power at a fundamental mode to an external load. In addition, the klystron has additional bunch-align-collect (BAC) cavities tuned to a higher harmonic frequency, and a harmonic output cavity and waveguide coupled via a window to an additional external load.

A depressed beam collector and an RF source comprising a depressed beam collector. The RF source may include, e.g., a multi-beam klystron, a single beam klystron, or other RF sources having an electron gun. The beam collector collects spent electrons from the electron gun and comprises a grounded portion configured to collect a portion of electrons entering the collector and a biased portion configured to collect another portion of the electrons entering the collector and having a depressed energy.

A depressed beam collector and an RF source comprising a depressed beam collector. The RF source may include, e.g., a multi-beam klystron, a single beam klystron, or other RF sources having an electron gun. The beam collector collects spent electrons from the electron gun and comprises a grounded portion configured to collect a portion of electrons entering the collector and a biased portion configured to collect another portion of the electrons entering the collector and having a depressed energy.

According to one embodiment, a klystron includes a high-frequency interaction unit, a main magnet arranged in a ring shape around the high-frequency interaction unit, an output waveguide, an auxiliary magnet arranged in a ring shape opposing the output waveguide, an output unit for extracting high-frequency power from the output waveguide, and an output adjustment mechanism which adjusts the output of the high-frequency power extracted from the output unit by deforming the output waveguide. In the output adjustment mechanism, the output waveguide is deformed by engaging a distal end of a jig inserted from an outside of the auxiliary magnet via a jig insertion hole with an engagement member and pushing or pulling the engagement member.

According to one embodiment, a klystron includes a high-frequency interaction unit, a main magnet arranged in a ring shape around the high-frequency interaction unit, an output waveguide, an auxiliary magnet arranged in a ring shape opposing the output waveguide, an output unit for extracting high-frequency power from the output waveguide, and an output adjustment mechanism which adjusts the output of the high-frequency power extracted from the output unit by deforming the output waveguide. In the output adjustment mechanism, the output waveguide is deformed by engaging a distal end of a jig inserted from an outside of the auxiliary magnet via a jig insertion hole with an engagement member and pushing or pulling the engagement member.