Abstract: Axially symmetric magnetic fields are provided about the longitudinal axis of each beam of a multi-beam electron beam device. The magnetic field symmetry is independent of beam voltage, beam current and applied magnetic field strength. A flux equalizer assembly is disposed between the cathodes and the anodes and near the cathodes of a multi-beam electron beam device. The assembly includes a ferromagnetic flux plate completely contained within the magnetic focusing circuit of the device. The flux plate includes apertures for each beam of the multi-beam device. A flux equalization gap or gaps are disposed in the flux plate to provide a perturbation in the magnetic field in the flux plate which counters the asymmetry induced by the off-axis position of the beam. The gaps may be implemented in a number of ways all of which have the effect of producing a locally continuously varying reluctance that locally counters the magnetic field asymmetry.

Abstract: An electrode structure for a vacuum tube is formed by having a ceramic insulating body act as the tube wall. Electrode areas are formed on the inside of the tube by coating the inside of the tube wall with a conductor. These electrode areas are then coupled, as necessary, to external electronic circuits. The coupling may be performed by through-wall connections, metallized abutting connections and other conventional means. The ceramic insulating body may be generally cylindrical in shape and may be formed of a material such as aluminum nitride, beryllium oxide, aluminum oxide and the like.

Abstract: A klystron tube for amplifying signals at microwave radio frequencies utilizes an electron source for emitting electrons through a field focused by a high energy magnet in the RF section of the tube. After the electrons have passed through the active area of the tube, the electrons strike the collector which, in this case, is a multistage depressed collector. The multiple stages of the depressed collector are connected to high energy voltage sources of different potentials. The magnet used for focusing the electron beam is closed (no open pole pieces) at the multistage depressed collector so that no magnetic flux reversals are present to affect the beam dispersal, due to electrostatic space charge forces, onto the multistage depressed collector.

Abstract: A microwave applicator for heating a moving fluid includes a heating chamber having a fluid inlet and a fluid outlet and through which the fluid to be heated flows. The applicator also includes a microwave energy source and a microwave circuit having at least one wave-guide element. The microwave circuit transforms microwave energy from the microwave source into a cylindrical wave-guide mode within the heating chamber for uniformly heating fluid flowing through the heating chamber. This technology is also applied as a method for applying microwave energy for heating a moving fluid. This method includes passing a fluid from a fluid inlet, through a heating chamber, and out a fluid outlet; and applying a microwave energy source through a microwave circuit including at least one wave-guide element to transform microwave energy from the microwave energy source into a cylindrical wave-guide mode within the heating chamber to uniformly heat the fluid flowing through the heating chamber.

Abstract: Axially symmetric magnetic fields are provided about the longitudinal axis of each beam of a multi-beam electron beam device. The magnetic field symmetry is independent of beam voltage, beam current and applied magnetic field strength. A flux equalizer assembly is disposed between the cathodes and the anodes and near the cathodes of a multi-beam electron beam device. The assembly includes a ferromagnetic flux plate completely contained within the magnetic focusing circuit of the device. The flux plate includes apertures for each beam of the multi-beam device. A flux equalization gap or gaps are disposed in the flux plate to provide a perturbation in the magnetic field in the flux plate which counters the asymmetry induced by the off-axis position of the beam. The gaps may be implemented in a number of ways all of which have the effect of producing a locally continuously varying reluctance that locally counters the magnetic field asymmetry.

Abstract: A crossed-field device such as a crossed-field amplifier or magnetron has a cathode body portion and an anode which cooperates with a crossed magnetic field to maintain emitted electrons on cycloidal paths and amplify an input signal or develop a microwave or millimeter wave output signal in an interaction space. The device is switched to shut down between working cycles, and delayed and secondary emissions are reduced to allow low noise operation and reduce multipactor for dependable operation at lower magnetic field strengths. Ceramic windows cover the output transformer (and input transformer in an amplifier device), and at least one window is grooved to reduce its secondary electron yield while maintaining its rf aperture. In addition, one or more walls within the device are physically structured or chemically treated or arranged to further address multipactor, allowing operation at reduced magnetic field strengths.

Abstract: A crossed-field device such as a crossed-field amplifier or magnetron has a generally peripheral cathode body portion and an anode which cooperates with a crossed magnetic field to maintain emitted electrons on cycloidal and amplify an rf input signal as it travels to an rf outlet. A control electrode positioned generally at a drift region away from the crossed-field amplification region interrupts the sustained electron emission to shut down the device between working cycles, and an auxiliary electrode positioned internally of the cathode diverts electrons into a gap proximally of the control electrode to reduce the control electrode energy requirements. The cathode is carried by a support structure, and the auxiliary electrode may be a rod axially extending in a counter-bore in the support structure. The auxiliary electrode is dc biased and may advantageously operate at anode potential, thereby obviating the need for any additional power source for the auxiliary electrode.

Abstract: A two-stage high power converter produces a highly regulated DC voltage from unregulated DC input. The first stage, having a plurality of interleaved buck regulators connected in parallel, converts unregulated DC voltage into regulated DC current. The second stage comprises a bridge for receiving the regulated current from the first stage, and converting it into AC voltage, which is in turn applied a step-up transformer. The secondary voltage of the transformer is rectified and filtered to produce low noise DC voltage. A method of converting unregulated DC voltage into regulated DC voltage comprises paralleling a plurality of interleaved buck regulators, where each of the buck regulators includes a switch. Each of the switches is controlled to operate at the same set frequency equal to two times the bridge operating frequency divided by the number of interleaved buck regulators. The combined current from interleaved buck regulators is fed to the bridge.

Abstract: An Inductive Output Tube where, in order to permit the use of coaxial output cavities, the electron beam propagates in first approximation in a radial direction from the cathode. The electron beam is generated by an in first approximation cylindrical cathode, and gated by a consequently in first approximation cylindrical grid. The required drive power is provided by a coaxial input circuit. Depending on the level of a bias voltage, V.sub.g, applied between grid and cathode, the radial electron beam can optionally be operated in modulation classes A, AB, B or C. The modulated electron beam, accelerated by the beam voltage applied between cathode and anode, passes through an in first approximation cylindrical output gap where the modulation interacts with the electromagnetic field of a coaxial output circuit which is optionally connected to one or both ends of the gap between anode and collector. The spent beam is then collected by a radial collector.

Abstract: A vacuum tube for handling an r.f. signal having a predetermined frequency range comprises a cathode, a heater, and a non-electron emissive grid. The grid is positioned from the cathode by the distance an emitted electron from the cathode can travel in a quarter cycle of the r.f. signal. Outer and inner metal tubes forming a resonant line of a signal coupler are respectively connected to the grid and cathode. R.F. absorbers absorb r.f. fields in an interaction region between an anode and the grid. In one embodiment a coupling loop is between metal tubes at an end of the tubes spaced n.lambda./4 from the grid and cathode. In a second embodiment the coupler includes a coaxial line having an inner conductor connected to a first metal face, spaced from a second opposed metal face by a solid dielectric. An outer conductor is connected to a third metal face, spaced from a fourth opposed metal face by the dielectric. The third and fourth faces surround the first and second faces.

Abstract: An inductive output tube, e.g., a KLYSTRODE, or a klystron, has a substantially hollow electron beam traversing a resonant cavity excited to the TM.sub.0x0 mode, where x is greater than 1.

Abstract: The frequency of an AC signal is multiplied by a factor N, where N is an integer greater than one, by an electron tube including a cathode for emitting an electron beam and a grid including N segments in proximity to the cathode. The grid is biased and coupled to the signal so the beam is formed as N groups of electron bunches during each cycle of the signal. Each segment accelerates one group of bunches for a duration of about 1/N th of each cycle of the signal. Different groups of bunches associated with the different segments are accelerated at phases displaced from each other during each cycle of the signal. In response to the N groups of bunches an output signal having a frequency N times that of the signal is derived.

Abstract: A vacuum tube for handling an r.f. signal having a predetermined frequency range comprises a linear electron beam emitting cathode, a heater and a non-electron emissive current modulating grid. The grid is positioned from the cathode by the distance an emitted electron from the cathode can travel in a quarter cycle of the r.f. signal. Outer and inner coaxial metal tubes forming a resonant line of a signal coupler are respectively connected to the grid and cathode so electrons passing through the grid are in bundles in an interaction region between an accelerating anode and the grid. Ferrite tiles absorb r.f. fields in the interaction region. In one embodiment a signal coupling loop is between metal tubes at an end of the tubes spaced 3.lambda./4 from the grid and cathode. In a second embodiment the coupler includes a low voltage coaxial line having an inner conductor connected to a first metal face, spaced from a second opposed metal face by a solid dielectric.