Provided are a traveling wave tube and a high-frequency circuit system such that the product life span of the traveling wave tube operating in multiple modes can be extended while variations in gain and amplification efficiency that accompany switching of the operation modes can be suppressed. The traveling wave tube comprises: an electron gun equipped with a cathode that releases electrons, and a heater that provides the cathode with heat energy for releasing the electrons; a helix causing an RF signal to interact with an electron beam formed from the electrons released by the electron gun; a collector for catching the electron beam emitted by the helix; an anode whereby the electrons released from the electron gun are guided into the helix; and a magnetic field application device for generating a magnetic field in order to change the diameter of the electron beam, said magnetic field application device being supplied with electric power for generating the magnetic field from the outside.

Provided are a traveling wave tube and a high-frequency circuit system such that the product life span of the traveling wave tube operating in multiple modes can be extended while variations in gain and amplification efficiency that accompany switching of the operation modes can be suppressed. The traveling wave tube comprises: an electron gun equipped with a cathode that releases electrons, and a heater that provides the cathode with heat energy for releasing the electrons; a helix causing an RF signal to interact with an electron beam formed from the electrons released by the electron gun; a collector for catching the electron beam emitted by the helix; an anode whereby the electrons released from the electron gun are guided into the helix; and a magnetic field application device for generating a magnetic field in order to change the diameter of the electron beam, said magnetic field application device being supplied with electric power for generating the magnetic field from the outside.

A traveling wave tube system includes a traveling wave tube, and a power supply device for supplying required power supply voltages to the respective electrodes of the traveling wave tube. The power supply device includes a control voltage generation circuit for generating a control voltage which is a negative DC voltage on the basis of a ground potential and supplying the control voltage to the anode, an anode voltage generation circuit for generating an anode voltage which is a negative DC voltage on the basis of the potential of the anode and supplying the anode voltage to the cathode, and a collector voltage generation circuit for generating a collector voltage which is a positive DC voltage on the basis of the potential of the cathode and supplying the collector voltage to the collector.

A traveling wave tube system includes a traveling wave tube, and a power supply device for supplying required power supply voltages to the respective electrodes of the traveling wave tube. The power supply device includes a control voltage generation circuit for generating a control voltage which is a negative DC voltage on the basis of a ground potential and supplying the control voltage to the anode, an anode voltage generation circuit for generating an anode voltage which is a negative DC voltage on the basis of the potential of the anode and supplying the anode voltage to the cathode, and a collector voltage generation circuit for generating a collector voltage which is a positive DC voltage on the basis of the potential of the cathode and supplying the collector voltage to the collector.

A collector for a traveling wave tube has at least two stages and an entrance opening for receiving an electron beam, which is followed by a first collector stage, wherein the first collector stage including magnetic focusing and a final collector stage being electrostatically designed, wherein a high-voltage connection of the first collector stage is led radially outwards in the region of the first collector stage adjacent to the final collector stage or adjacent to one or more further collector stages via a high-voltage feedthrough radially outward, wherein a ceramic insulation sleeve is connected to an outer side of an electrode of the last collector stage immediately adjacent and free of high-voltage feedthroughs.