A magnetic field generation apparatus is provided for a magnetron including a permanent magnet arrangement and a magnetic field conductor device. The magnetic field conductor device has a diverting element. The diverting element, which includes a plurality of rectangular diverting segments, is arranged detachably on the magnetic field generation apparatus during maintenance work in order to deflect a magnetic field generated by the permanent magnet arrangement away from further components of the magnetic field generation apparatus and components of the magnetron. A magnetron includes a magnetron tube and such a magnetic field generation apparatus. In a method for replacing an old magnetron tube of such a magnetron with a new magnetron tube, the diverting element is arranged on the magnetic field generation apparatus, and the old magnetron tube is removed from the magnetron and replaced with the new magnetron tube in order to then remove the diverting element again.

A radially-fed RF power combiner combines a plurality of input signals to generate a single fundamental-mode transverse electromagnetic (TEM) output. The combiner comprises a vacuum coaxial transmission line having a plurality of coaxial vacuum feedthroughs configured to receive the input signals. The feedthroughs are arranged radially around the vacuum coaxial transmission line. The inner conductive surface of the vacuum coaxial transmission line may comprise a cylindrical conductive base and a plurality of radially-aligned conductive ridges azimuthally distributed within a vacuum envelope of the vacuum coaxial transmission line. Each of the conductive ridges may be coupled to a center conductor of a corresponding one of the coaxial vacuum feedthroughs. The conductive ridges may have a taper to provide an increasing gap between the top of the conductive ridges and an outer conductive surface of the vacuum coaxial transmission line. The increasing gap may gradually transition the input signals from each coaxial vacuum feedthrough to quasi-TEM mode signals within the vacuum envelope allowing the quasi-TEM mode signals from each conductive ridge to spread azimuthally within the vacuum envelope and combine to generate a substantially pure TEM mode signal.

A radially-fed RF power combiner combines a plurality of input signals to generate a single fundamental-mode transverse electromagnetic (TEM) output. The combiner comprises a vacuum coaxial transmission line having a plurality of coaxial vacuum feedthroughs configured to receive the input signals. The feedthroughs are arranged radially around the vacuum coaxial transmission line. The inner conductive surface of the vacuum coaxial transmission line may comprise a cylindrical conductive base and a plurality of radially-aligned conductive ridges azimuthally distributed within a vacuum envelope of the vacuum coaxial transmission line. Each of the conductive ridges may be coupled to a center conductor of a corresponding one of the coaxial vacuum feedthroughs. The conductive ridges may have a taper to provide an increasing gap between the top of the conductive ridges and an outer conductive surface of the vacuum coaxial transmission line. The increasing gap may gradually transition the input signals from each coaxial vacuum feedthrough to quasi-TEM mode signals within the vacuum envelope allowing the quasi-TEM mode signals from each conductive ridge to spread azimuthally within the vacuum envelope and combine to generate a substantially pure TEM mode signal.

A lightweight, thermally stable disk for use in a slow wave structure (SWS) of CoTWT is configurated without sacrificing thermal management, structural integrity, or RF performance. Refractory metal is removed from regions of the disk where no RF interaction is expected and replaced with resistive ceramic material. The disk includes one or more central ribs positioned about the periphery of a central hub. A plurality of U-shaped receptacles may extend from the one or more central ribs. The disk is plated with a patterned metal to define laminar conductive tabs spaced around the periphery that are separated by solid resistive ceramic tabs and to electromagnetically connect all exposed refractory metal surfaces. The plating metal must be capable of being deposited and patterned in a thin layer of 10 to 100 microns, exhibit a Young's Modulus of <100 GPa to provide both the ductility and malleability to plastically deform and exhibit an electrical conductivity at least and preferably greater than that of the refractory metal.

A lightweight, thermally stable disk for use in a slow wave structure (SWS) of CoTWT is configurated without sacrificing thermal management, structural integrity, or RF performance. Refractory metal is removed from regions of the disk where no RF interaction is expected and replaced with resistive ceramic material. The disk includes one or more central ribs positioned about the periphery of a central hub. A plurality of U-shaped receptacles may extend from the one or more central ribs. The disk is plated with a patterned metal to define laminar conductive tabs spaced around the periphery that are separated by solid resistive ceramic tabs and to electromagnetically connect all exposed refractory metal surfaces. The plating metal must be capable of being deposited and patterned in a thin layer of 10 to 100 microns, exhibit a Young's Modulus of <100 GPa to provide both the ductility and malleability to plastically deform and exhibit an electrical conductivity at least and preferably greater than that of the refractory metal.

An axially-fed RF power combiner combines a plurality of input signals to generate a single fundamental-mode transverse electromagnetic (TEM) output. The combiner comprises a vacuum coaxial transmission line having a plurality of coaxial vacuum feedthroughs configured to receive the input signals. The feedthroughs are arranged axially around the vacuum coaxial transmission line. An increasing gap is provided between the inner conductive surface and the outer conductive surface of the vacuum coaxial transmission line to gradually transition the input signals from each coaxial vacuum feedthrough to quasi-TEM mode signals within the vacuum envelope of the vacuum coaxial transmission line. In some conductive-ridge embodiments, the inner conductive surface of the vacuum coaxial transmission line may comprise a cylindrical conductive base and a plurality of radially-aligned conductive ridges azimuthally distributed within a vacuum envelope of the vacuum coaxial transmission line. In some ridge-less embodiments, the inner conductive surface includes a tapered region within the vacuum envelope to provide an increasing gap between the inner conductive surface and the outer conductive surface.

An axially-fed RF power combiner combines a plurality of input signals to generate a single fundamental-mode transverse electromagnetic (TEM) output. The combiner comprises a vacuum coaxial transmission line having a plurality of coaxial vacuum feedthroughs configured to receive the input signals. The feedthroughs are arranged axially around the vacuum coaxial transmission line. An increasing gap is provided between the inner conductive surface and the outer conductive surface of the vacuum coaxial transmission line to gradually transition the input signals from each coaxial vacuum feedthrough to quasi-TEM mode signals within the vacuum envelope of the vacuum coaxial transmission line. In some conductive-ridge embodiments, the inner conductive surface of the vacuum coaxial transmission line may comprise a cylindrical conductive base and a plurality of radially-aligned conductive ridges azimuthally distributed within a vacuum envelope of the vacuum coaxial transmission line. In some ridge-less embodiments, the inner conductive surface includes a tapered region within the vacuum envelope to provide an increasing gap between the inner conductive surface and the outer conductive surface.

A high power RF energy device component is disclosed that is exposed to high power RF energy in a vacuum environment, and includes a multipactor-inhibiting carbon nanofilm covering at least one surface of the component. A secondary electron efficiency emission (SEE) coefficient of the multipactor inhibiting carbon nanofilm is desirably less than a SEE coefficient of the underlying surface of the component.

A high power RF energy device component is disclosed that is exposed to high power RF energy in a vacuum environment, and includes a multipactor-inhibiting carbon nanofilm covering at least one surface of the component. A secondary electron efficiency emission (SEE) coefficient of the multipactor inhibiting carbon nanofilm is desirably less than a SEE coefficient of the underlying surface of the component.

Provided are a magnetron and a microwave heating device. The magnetron includes a tube core, a first tube shell, a second tube shell, an output ceramic, an antenna cap, and an antenna. The first tube shell, the tube core, the second tube shell, the output ceramic, and the antenna cap are connected in sequence. The antenna extends into the tube core, and sequentially passes through the second tube shell and the output ceramic and extends into the antenna cap. A height H1 of the second tube shell relative to the tube core is smaller than or equal to 14 mm, and a ratio H1/S of a height H1 of the tube core to a cross-sectional area S of the antenna ranges from 0.4 to 3.3.