| NEC Microwave Tube, Ltd. Patent applications |
| Patent application number | Title | Published |
|---|
| 20090033228 | POWER SUPPLY APPARATUS AND HIGH-FREQUENCY CIRCUIT SYSTEM - A power supply apparatus for a traveling-wave tube includes an electrical discharge switch and a first resistor that are serially connected, and that are connected between a cathode electrode and a first collector electrode; N (N denotes a positive integer) arresters that are serially connected, and that are inserted between a ground potential and a connection node of the electrical discharge switch and the first resistor; N second resistors that are inserted between the N arresters and a second collector electrode to an Nth collector electrode and a ground potential, respectively; and an electrical discharge control circuit that turns off the electrical discharge switch at a time of normal operation of the power supply apparatus and turns on the electrical discharge switch when stopping operation of the power supply apparatus. | 02-05-2009 |
| 20090009086 | TRAVELING WAVE TUBE - A bottom portion of a metal tape is attached to an end portion of a helix. A coaxial inner conductor for input or output of a high frequency signal is fixed by its end portion being interposed between upright surfaces of the metal tape. The metal tape is joined to the coaxial inner conductor by being laser-welded to opposite side surfaces of the coaxial inner conductor. | 01-08-2009 |
| 20080246553 | STRUCTURE OF COAXIAL-TO-WAVEGUIDE TRANSITION AND TRAVELING WAVE TUBE - The present invention includes a waveguide for outputting radio frequency wave, a vacuum envelope provided with a slow-wave circuit, a coaxial connection part connecting the waveguide and the vacuum envelope, an insulating window member which is provided in the coaxial connection part and which hermetically seals a said of vacuum envelope and a said of waveguide, a coaxial center conductor of exterior portion with one end supported by the waveguide, and a coaxial center conductor of an interior portion with one end abutting on the slow-wave circuit and the other end connected to the coaxial center conductor of the exterior portion. The waveguide is provided with a screw part supporting the coaxial center conductor of the exterior portion movably in an axial direction of the coaxial center conductor of the exterior portion. An end portion of the coaxial center conductor of the exterior portion is connected to the end portion of the coaxial center conductor of the interior portion movably in the axial direction of the coaxial center conductor of the exterior portion. | 10-09-2008 |
| 20080231197 | POWER SUPPLY UNIT, HIGH-FREQUENCY CIRCUIT SYSTEM AND HEATER VOLTAGE CONTROL METHOD - At the time of restoration of the power supply after a power failure, a voltage higher than that in the normal operation mode is supplied to a heater. After a lapse of a predetermined time, the voltage to be supplied to the heater is switched into the voltage in the normal operation mode while a control signal for stating the operation of an electron tube is output. Alternatively, at the time of power activation, the rate of change of current flowing through a heater is determined for every period of time. When the rate of change becomes equal to or lower than a predetermined threshold, a voltage higher than that in the normal operation mode is supplied to the heater, and after a lapse of a predetermined time, the voltage to be supplied to the heater is switched into the voltage in the normal operation mode while a control signal for stating the operation of the electron tube is output. | 09-25-2008 |
