Abstract: A digital cathode current control circuit for controlling the cathode current of a traveling wave tube (TWT) amplifier is disclosed. The cathode current control circuit includes circuitry for providing a comparison signal indicative of the occurrence and amplitude of TWT cathode current pulses; clocking circuitry responsive to the comparison signal for providing a clock signal delayed relative the occurrence of a cathode current pulse; comparison circuitry for comparing the comparison signal with predetermined reference signals indicative of a predetermined cathode current level, and for providing adjustment signals indicative of the adjustment of the TWT cathode current necessary to tend to achieve the predetermined cathode current; and counter circuitry clocked by the delayed clock signal for providing an output count in response to the adjustment signals.

Abstract: An improved mounting structure for spatially disposing from its long axial conductive member, a filament within the outer envelope of an incandescent lamp is disclosed. The mounting structure offsets the filament from the centerline of the lamp and from its conductive members so as to substantially reduce the typically experienced arcing condition between the conductive members of the mounting structure and the filament.

Abstract: The invention comprises a self-adjusting ballast system for a high intensity discharge lamp. The ballast has a current limiter which modifies the lamp's present duty cycle to prevent damage if bulb rectification or another overcurrent condition occurs. It also has a current integration feedback loop for controlling lamp current during start-up.

Abstract: This invention provides for an improved reflector-type lamp having reduced focus loss and exhibiting an increase in reflector collection efficiency. Stray light from the lamp's light source is reduced and channeled into the central angular region of the reflector where it can be more easily controlled and increase the in candle power of the lamp. A shorter, more compact filament design, wound with larger mandrel ratios, is positioned within the reflector to evenly disperse the light energy throughout the central angular region.

Abstract: A circuit for repetitively firing a flash or strobe lamp with voltage derived from the AC line without large and costly storage capacitors utilizes a voltage doubler having small capacitors one microfarad in capacitance value or less. A trigger circuit provides a high potential pulse to the trigger electrode of the lamp at or near the peak of the voltage from the AC line to provide flashes at a desired rate, say one per second. The circuit may be used in a warning light device.

Abstract: A broad-beam electron source has a chamber into which is introduced an ionizing gas. Electrons are emitted between a cathode and an anode assembly to ionize that gas. The electrons within the plasma are drawn outwardly from the chamber through an apertured wall, which constitutes a screen, and thereafter are accelerated toward a target in a well-directed beam. A comparatively copious supply of electrons is developed, while yet requiring only low voltages in connection with its generation and resulting in correspondingly low electron energies. Ions produced external to the electron source itself are utilized to assist in neutralizing the charge density of the electron beam in order to help maintain its definition. For insulative targets, secondarily emitted electrons permit conservation of surface charge.

Abstract: This invention provides an improved compact fine wire incandescent lamp filament and method for making such having a primary mandrel ratio in the range of about 1.40 to about 4.00 and a secondary mandrel ratio which is greater than or equal to the primary mandrel ratio. The improved filament design exhibits an increase in compactness and retains or increases structural rigidity while exhibiting minimal sag when the filament is incorporated into an incandescent lamp of the tungsten halogen type variety. The compact coiling method is particularly useful in designing compact filaments for high voltage applications where it is desirable to eliminate the use of rectifying means to lower the effective voltage across the filament.

Abstract: A discharge lamp operating device having a high frequency inverter is discharged. Connected to a secondary winding of an oscillation transformer of the high frequency inverter is a discharge current supply circuit having a switch for controlling supply of a discharge current to dim a fluorescent lamp. An electrode heating circuit is connected to secondary windings of the transformer to continuously heat electrodes. An oscillation frequency of the inverter is controlled such that it increases as a dimming factor is high and decreases as the dimming factor is low. A capacitor is connected in series with a path of an electrode heating current in the electrode heating circuit so that the heating current is increased when the dimming factor is high and decreased when it is low by utilizing a frequency dependency of an impedance of the capacitor.

Abstract: A circuit is disclosed herein for use in series with a fluorescent lamp and a conventional ballast for supplying operating current to the lamp when the main line source of power has been interrupted. The circuit includes a sensor for detecting the lamp current and utilizes the lamp current for charging a storage battery via a battery charger. An inverter ballast circuit is normally maintained in an "OFF" condition by the sensor and is responsive to the sensor when the power source to the lamp has been interrupted so that the power from the battery is applied to the inverter ballast to turn it to the "ON" condition. Conduction of the inverter ballast circuit provides AC voltage to energize the fluorescent lamp through the conventional ballast.

Abstract: A decorative device is disclosed which includes a motor, music module or other electrical loads and electrical circuitry and a connector for connection to a selected socket of a string of conventional sockets for connection to an A.C. line. The connector includes an elongated flexible cable and is constructed to permit ready installation and positioning. Lamps may be provided in the device. The electrical circuit includes a bridge rectifier and Zener diodes connected to insure continuous energization of lamps of the string while protecting against excessive voltages and minimizing safety hazards.

Abstract: A self-adjusting ballast system for a high intensity discharge lamp. A lightweight, inexpensive and efficient ballast controls the strike and warmup stages of the high intensity discharge lamp, in particular high wattage lamps, through direct sensing of the radiant energy or heat output of the lamp itself. A current controller corrects for current imbalance in the alternating current lamp circuit due to bulb rectification or magnetic imbalance in the inverter transformer system.

Abstract: The structure is material such as a ceramic in the form of a bundle of open cells, a "honeycomb", with the shape of the cells corresponding to the shape of the openings desired in the grid. The cathode is formed in the cells, rather than adding the grid to a ready-made cathode. The grid is formed by coating the end of the cell walls with a conducting material (metal and/or carbon). The surface of the cathode is suitably recessed from the grid.

Abstract: In a power-line-operated inverter-type power supply for the magnetron in a microwave oven, power is provided to the magnetron from the inverter by way of a series-excited resonant LC circuit, the magnetron load being connected in parallel with the tank capacitor of this L-C circuit. This arrangement provides for good matching between the output characteristics of the inverter and the operating characteristics of the magnetron. To prevent potentially destructive overload of the inverter, as may occur if the inverter's output voltage is series-applied to the resonant L-C circuit before the magnetron is ready to absorb power, inverter oscillation is not initiated until after the magnetron cathode has been heated to incandescence.

Abstract: High-efficiency inverter circuits, particularly half-bridge devices, are especially suitable for energizing gas discharge lamps. The inverters preferably employ a series-connected combination of an inductor and a capacitor to be energized upon periodic transistor conduction. Transistor drive current is preferably provided through the use of at least one saturable inductor to control the transistor inversion frequency to be equal to or higher than the natural resonant frequency of the inductor and capacitor combination. The inverters can develop high output voltages to supply external loads connected to the inductor-capacitor combinations.

Abstract: The cathode and tube of this invention comprise a secondary emission semiconductor cathode in a crossed-field high power amplifier. A gallium arsenide semiconductor doped with an impurity to make it more conductive than intrinsic gallium arsenide has been found to perform better than prior art secondary emission cathodes when it is incorporated as a cathode in a high-power crossed-field amplifier tube operating at high average and peak current. With a gallium arsenide cathode, the crossed-field amplifier tube exhibits a radio frequency output pulse which has fast rise time and much reduced leading-edge jitter relative to performance of the same cross-field amplifier tube having a conventional secondary emission cathode.

Abstract: In a display device provided with a main substrate having the lower surface on which a metallic layer is formed and the upper surface on which at least a power source or a deflection circuit is arranged, a plate member having one surface formed by an insulating material and the other surface formed by a metallic material is placed with its insulating material facing the lower surface of the main substrate.

Abstract: Disclosed are a method and apparatus for rapidly heating a thermionic vacuum tube cathode, thereby enabling the vacuum tube to be placed in useful operation shortly after the tube is switched on. Rapid heating of the cathode is achieved by passing current through the cathode, thereby directly heating it. Simultaneously, the cathode is also heated by an indirect radiant heater and by electron bombardment by electrons emitted from the heater. When the cathode reaches its operating temperature, the direct heating current and the electron bombardment are stopped and the cathode is maintained at its operating temperature by the indirect heater alone. Cathode warm-up times of less than 1 second may be attained using this invention.

Abstract: An electronic ballast is adapted for operation on regular 120 volt/60 Hz power line voltage and comprises: (i) full bridge rectifier means, (ii) ripple filter means consisting of an LC circuit series-resonant at 120 Hz, (iii) self-oscillating inverter means operating into an LC output circuit parallel-resonant at about 30 kHz, and (iv) means to disable the inverter in case a 30 kHz ground-fault current flows from its output circuit. A key element in achieving high reliability as well as high durability relates to the use of the series-resonant LC circuit instead of the conventional electrolytic capacitor for DC voltage ripple filtering. A key element in achieving high efficiency relates to the use of ground-fault interruption to achieve the required safety from electric shock hazard, thereby obviating the need for the more conventionally used isolation transformer with its attendant added cost and inefficiency.

Abstract: In a microwave discharge light source apparatus for effecting discharge of an electrodeless discharge lamp held in a cavity which causes resonance by microwaves, the wall surface of the cavity resonator is constituted by a mesh and wires constituting the mesh, are electrically connected at each crossing point without resistance of contact. Effective discharging of the lamp is attainable and the cavity has a mechanically strengthened structure.

Abstract: The enclosed electronic flash device for a camera includes a booster circuit connectible to an electrical power source or battery, a high voltage rectifier diode for rectifying the output of the booster circuit, and a storage capacitor. A main power supply switch and an auxiliary power supply switch are connected in series between the negative poles of the power source and capacitor. The auxiliary power supply switch is arranged to close when the flash device is attached to the camera. A signal terminal is connected to the negative pole of the storage capacitor through other circuit elements and another signal terminal is connected to one contact of the auxiliary power supply switch, which is connected in turn to the negative pole of the storage capacitor. The auxiliary power supply switch is connected in series with the main power supply switch at a point farther from the negative terminal of the battery than the main power supply switch.