Abstract: A power supply apparatus for supplying predetermined supply voltages respectively to an anode electrode, a cathode electrode, a collector electrode, and a helix of an electron tube. The power supply apparatus comprises an anode switch for turning on/off the anode voltage output, and an anode switch control circuit for controlling the on/off operation of the anode switch such that a pulsed anode voltage is repeatedly applied to the anode electrode a plurality of times at a predetermined period when operation of a helix power supply and a collector power supply is stopped.

Abstract: A collector in a microwave tube has a collector electrode for capturing an electron beam radiated from an electron gun and passing through a slow wave circuit, an insulator disposed in contact with the outer peripheral surface of the collector electrode, and a radiator disposed in contact with the outer peripheral surface of the insulator, wherein the insulator, the outer diameter of the collector electrode, and the inner diameter of the radiator are tapered in the axial direction of the tube.

Abstract: A microwave tube has a configuration in which the connection between an anode electrode and the helix is cut, the helix is grounded, and a current suppression element is provided between the anode electrode and ground voltage for suppressing the continuous time interval of the flow of an excess current to the helix that is caused by discharge to a time interval range that does not threaten damage to the helix, i.e., to a time interval range in which an alarm signal is not supplied.

Abstract: An electron tube is provided with a plurality of supports, a portion of the support covered with conductive material abuts the inner wall of the shell, and another portion of the support covered with dielectric abuts the helix. The helix which is used as a high-frequency circuit for bringing about interaction between an electron beam and a high-frequency signal is supported and fixed within the shell by plurality of supports.

Abstract: A disk-shaped cathode pellet is installed and secured by a retainer onto a heater cap that incorporates a heater. The part of this retainer that covers the periphery of the electron emission surface of the cathode pellet functions as a portion of a Wehnelt electrode. Alternatively, the retainer is formed such that the average angle of the surface with respect to the outermost shell of the electron beam matches the Pierce angle such that the part of this retainer that covers the periphery of the electron emission surface of the cathode pellet functions as a Wehnelt electrode.

Abstract: A high pressure discharge lamp includes a quartz glass bulb, a conductive element which is sealed at a sealing portion of the bulb, and a pair of electrodes. Each electrode is disposed in the quartz glass bulb so as to be opposite the other and connected to the conductive element. A part of each electrode is sealed with the quartz glass bulb at the sealing portion so as to generate a contacting portion formed by the part of each electrode and the bulb. The maximum length, Lmax, of the contacting portion is defined as: Lmax (mm)?200/(P×D); and the minimum length, Lmin, of the contacting portion is defined as: Lmin (mm)?0.8/(D2×?) or Lmin (mm)?0.7 whichever is longer, where D is the diameter (mm) of the electrode and P is the power (W) supplied to the electrode.

Abstract: A traveling-wave tube is provided which has a heat radiating structure with good heat conductivity from the collector core to the heat sink. An insulator is disposed around and in contact with the outer peripheral surface of a collector electrode and has a slit in parallel with a tube axis. A radiator is disposed outside of and in contact with the insulator and has a slot formed on the top surface thereof extending in parallel with the tube axis. The radiator also has one or more grooves that insect the slot and receive therein a fastening member having a length shorter than the length of the groove and formed with screwed holes extending through both end portions thereof in the axial direction. By adjusting amounts by which bolts are screwed into the fastening member through the throughholes formed through the radiator, the gaps in the groove between the radiator and both end surfaces of the fastening member can be varied.

Abstract: A power supply circuit for a traveling-wave tube disclosed herein eliminates a large relay and a relay driving power supply to reduce the size and cost and to make itself tolerable to vibrations and impacts. A first control device turns on, when a potential on a helix electrode rises to a predetermined threshold determined by the ratio of the resistance of a first resistor to the resistance of a second resistor with respect to a potential on a positive heater electrode or a negative heater electrode, to conduct from a first terminal to a second terminal of the first control device. A second control device turns on when the first control device is off to maintain an anode electrode and a cathode electrode at the same potential. The second control device turns off when the first control device turns on to generate a potential difference between the anode electrode and cathode electrode, thereby applying a voltage to the anode electrode.

Abstract: A power supply apparatus for a traveling-wave tube disclosed herein eliminates the need for isolation through a vacuum relay or the like, and is therefore fabricated in small size and at low cost. An oscillator circuit generates an oscillating signal at a frequency optionally selected from a plurality of frequencies. An inverter is applied with the oscillating signal from the oscillator circuit to generate an AC voltage signal at the frequency of the oscillating signal. A transformer transforms the AC voltage signal generated by the inverter disposed on the primary side and supplies the resulting signal to the secondary side. A rectifier circuit, which is disposed on the secondary side, rectifies the AC voltage signal transformed by the transformer for application to the traveling-wave tube. A frequency detector circuit detects the frequency of the AC voltage signal applied from the transformer to the rectifier circuit to generate a device control signal in accordance with the frequency.

Abstract: A high pressure discharge lamp includes a quartz glass bulb and a pair of electrodes. Each electrode of the pair of electrodes is disposed so as to be opposite the other in the quartz glass bulb. The quartz glass bulb of the high pressure discharge lamp contains at least mercury and a halogen gas which are airtightly sealed in the quartz glass bulb. The partial pressure of oxygen (O) in the quartz glass bulb is about 2.5×10?3 Pa or less and the partial pressure of the halogen gas in the quartz glass bulb is in the range between about 1×10?6 ?mol/mm3 and 1×10?8 ?mol/mm3. The pair of electrodes contain potassium oxide in the range between about 20 ppm and 40 ppm.

Abstract: A microwave tube has a configuration in which the connection between an anode electrode and the helix is cut, the helix is grounded, and a current suppression element is provided between the anode electrode and ground voltage for suppressing the continuous time interval of the flow of an excess current to the helix that is caused by discharge to a time interval range that does not threaten damage to the helix, i.e., to a time interval range in which an alarm signal is not supplied.

Abstract: A collector core of a microwave tube has an insulator and a radiator around a cylindrical outer peripheral portion thereof. The cylindrical insulator and radiator comprise a slit along a central axis of the collector core, respectively. These slits are arranged on mutually overlapped positions. Portions of the collector core corresponding to these slits are cut off so as to be flat or concave. These slits and the flat surface or the concave portion are arranged symmetrically in a section of the collector core.

Abstract: In a power-supply unit for a microwave tube, voltage between a helix power supply terminal and a cathode power supply terminal is divided into voltage slightly lower than the voltage of a collector power supply terminal. Uni-directional conductive means is provided between a voltage dividing point and the collector power supply terminal, and when the voltage of the collector power supply terminal is about to be lower than voltage at the voltage dividing point while the voltage approximates the voltage of the cathode power supply terminal, the uni-directional conductive means conducts and clamps the voltage of the collector power supply terminal so that the voltage is substantially equal to the voltage at the voltage dividing point.

Abstract: A high pressure discharge lamp includes a quartz glass bulb, a conductive element which is sealed at a sealing portion of the bulb, and a pair of electrodes. Each electrode is disposed in the quartz glass bulb so as to be opposite the other and connected to the conductive element. A part of each electrode is sealed with the quartz glass bulb at the sealing portion so as to generate a contacting portion formed by the part of each electrode and the bulb. The maximum length, Lmax, of the contacting portion is defined as: Lmax((mm))≦/200/(P×D); and the minimum length, Lmin, of the contacting portion is defined as: Lmin((mm))≧0.8/(D2×&pgr;) or Lmin((mm))≧0.7 whichever is longer, where D is the diameter ((mm)) of the electrode and P is the power (W) supplied to the electrode.

Abstract: An electron gun also has a cathode for emitting electrons, a heater cap which contains a heater for applying the cathode with thermal energy for emitting electrons, a retainer for securing the cathode on the heater cap by clamping the peripheral edge of the cathode onto the heater cap, and a cylindrical Wehnelt supporter. The cylindrical Wehnelt supporter has a Wehnelt electrode for focusing an electron beam that is formed in such a shape that an average angle of the surface thereof with respect to an outermost shell of the electron beam matches a Pierce angle, and three or more heater cap supporters for securely supporting the heater cap at a position at which an electron emitting surface of the cathode and an opening formed through the Wehnelt electrode satisfy a predetermined perveance.

Abstract: A high pressure discharge lamp includes a quartz glass bulb, a conductive element which is sealed at a sealing portion of the bulb, and a pair of electrodes. Each electrode is disposed in the quartz glass bulb so as to be opposite the other and connected to the conductive element. A part of each electrode is sealed with the quartz glass bulb at the sealing portion so as to generate a contacting portion formed by the part of each electrode and the bulb. The maximum length, Lmax, of the contacting portion is defined as: Lmax (mm)≦200/(P×D); and the minimum length, Lmin, of the contacting portion is defined as: Lmin (mm)≧0.8/(D2×&pgr;) or Lmin (mm)≧0.7 whichever is longer, where D is the diameter (mm) of the electrode and P is the power (W) supplied to the electrode.

Abstract: A high pressure discharge lamp includes a quartz glass bulb, a conductive element which is sealed at a sealing portion of the bulb, and a pair of electrodes. Each electrode is disposed in the quartz glass bulb so as to be opposite the other and connected to the conductive element. A part of each electrode is sealed with the quartz glass bulb at the sealing portion so as to generate a contacting portion formed by the part of each electrode and the bulb. The maximum length, Lmax, of the contacting portion is defined as: Lmax (mm)≦200/(P×D); and the minimum length, Lmin, of the contacting portion is defined as: Lmin (mm)≧0.8/(D2×&pgr;) or Lmin (mm)≧0.7 whichever is longer, where D is the diameter (mm) of the electrode and P is the power (W) supplied to the electrode.

Abstract: Expressing a perveance of an electron gun to be determined by a form of the electron gun as P&mgr;, a voltage to be impressed on an accelerating electrode Va and a beam current Ib, voltage Va which satisfies the following expression, Ib<P&mgr;×Va3/2 is impressed on the accelerating electrode. Further, the electric potential of the accelerating electrode is maintained at the highest level of all electrodes in the electron tube at all times.

Abstract: An electron tube for communication is provided with an output waveguide that is directly coupled to an outlet port of a RF (Radio Frequency) wave signal, and at least one of a low-pass filter, a high-pass filter, and a band-pass filter is included inside the output waveguide.

Abstract: Insulating ceramic parts for insulating collector electrodes in a traveling wave tube and a vacuum envelope are formed in a cylindrical shape in which the central axis of the inner diameter diverges from the central axis of the outer diameter and are constructed such that holes are provided in portions of the insulating ceramic parts where the thickness in the radial direction is great, and high-voltage leads for supplying prescribed voltages to said collector electrodes from the exterior pass through these holes.