Abstract: A circuit for starting and operating a low-voltage fluorescent lamp from a 120 volt AC supply. The circuit includes a choke type ballast connected in series with the lamp and inductively coupled to a pulse train generator comprising an RC energy storage circuit connected across the line and a voltage sensitive transistorized relaxation oscillator having a divider network for sensing lamp voltage. In a preferred embodiment the circuit is employed in a preheat mode of operation in combination with an electronic starter circuit comprising a PTC resistor, silicon diode and SCR series connected across the lamp.

Abstract: A high frequency and high voltage generating circuit for a discharge lamp lighting device controls its initial output at the starting time of a discharge lamp to prevent applying a high voltage to the discharge lamp in the "cold cathode" state. The circuit comprises in combination an oscillation circuit having an oscillation capacitor, a non-linear inductor and a thyristor, and an initial output limiter for delaying the output supply until the lamp filament is sufficiently preheated for preventing sputtering and for extending the operational life of the discharge lamp. The output control is formed as a bias circuit for the nonlinear inductor and includes a thermistor with a negative or a positive temperature coefficient.

Abstract: A novel transistorized fluorescent lamp ballast and lamp combination operates from AC line voltage. The ballast provides for "soft-start" lamp operation in one featured aspect and provides for some lamp light output regulation in another featured aspect thereof.

Abstract: The invention relates to an electric arrangement comprising two series-arranged discharge tubes which are provided with preheatable electrodes and which are stabilized by means of a relatively small ballast. The tubes are shunted by a semi-conductor switching element which operates in the operating condition of the tubes.According to the invention a control circuit of the semi-conductor switching element includes a non-linear circuit element which ensures that the discharge tubes do not ignite before the electrodes are in the warm state.

Abstract: A voltage multiplier device is disclosed which includes a circuit and a means for coupling the circuit between a television filament transformer and the heater filament leads of a C.R.T. picture tube of a television set. The device is operative to develop a voltage across the two leads of the C.R.T. heater filament that is greater than the voltage developed across the two secondary leads of the transformer.

Abstract: A indicator device with vacuum fluorescence elements controlled or triggered by a driving circuit, the heaters of the elements lying in a heating circuit. The heating circuit contains a switch which is controlled or triggered by a clock generator and the clock pulse frequency and the pulse duty factor of the control signal pulses are selected such that the effective value of the pulsed heating current is equal or approximately equal to the dc heating current in accordance with the elements.

Abstract: An improved ballast circuit for a low pressure gas discharge lamp having two filament type electrodes at opposite ends of the lamp is disclosed. The ballast circuit includes a first device for providing a high AC voltage for application across opposite electrodes of the lamp; a solid state controlled current source for providing a controlled current to the first device for enabling the first device to apply the AC voltage across the lamp electrodes to illuminate the lamp, wherein the voltage placed across said electrodes is non-sinusoidal; and a second device coupled to the first device for inhibiting the non-sinusoidal voltage from causing mercury migration in the lamp. The second device includes circuit connections for enabling current flow through only one filament of the lamp; and for biasing the voltage applied across the lamp about a DC level for balancing the effect upon mercury migration within the lamp caused by enabling current to flow through only the one filament.

Abstract: An electric discharge lamp circuit arrangement wherein rapid starting of the lamp is obtained by charging a ballast impedance capacitance via a unidirectional current conducting path in a sense such as to breakdown a voltage breakdown device in the control electrode lead of a controllable switching device connected with the lamp to provide a current path between the supply terminals comprising, in series, the capacitance, heating means for the lamp main electrodes and the switching device. On breakdown, the switching device temporarily conducts to complete the series path and cause a pulse of current to flow through the heating means, whereafter the capacitor recharges and a further current pulse is produced. The unidirectional current path may extend through the breakdown device or by-pass the breakdown device via a rectifier.

Abstract: In a magnetron device, a shield box is disposed covering a cathode stem and energizing power is supplied from the outside of the shield box to cathode lead terminals in the shield box.An energizing power supplying means comprises a transformer having a primary coil and a secondary coil which are both wound around a magnetic core and connect inductively the inner section of the shield box with the outer section. Thus high frequency noise which is a part of high frequency energy oscillated in anode resonant cavities and transmitted into the shield box through the cathode lead terminals is perfectly confined in the box. Therefore high frequency noise leaking out from the magnetron device toward a commercial power source is significantly reduced.

Abstract: An electronic starter for a discharge lamp includes an SCR controlled by a temperature-sensitive element and an auxiliary switch arranged so that no current flows in the temperature-sensitive element when the lamp is in operation, whereby rapid restarting of the lamp occurs after a brief interruption of the AC supply voltage. The temperature-sensitive element may be thermally coupled to an inductor in series with the lamp ballast thereby to limit the ballast current in the event the lamp fails to ignite.

Abstract: A magnetron energizing circuit preferably uses two transformers of the high leakage reactance type having isolated secondaries with an end terminal of each secondary connected to a common point which is at ground potential. The secondaries are connected to series condensers in two loops which provide leading current flowing in the secondaries at all times while both are connected in the circuit to produce saturation in the respective cores of the secondaries whereby to achieve substantially constant current and good regulation for variations in the primary voltage. A single magnetron is served by the circuit and variations in the loading of the magnetron are also compensated for by virtue of the substantially constant current circuit. The secondaries are connected in opposite phase with respect to the respective capacitors which they serve to charge to obtain a full wave doubler operation when the transformers are both in circuit but with low peak current.

Abstract: A starter circuit for a hot cathode discharge lamp which has a switching element which is connected across the lamp to permit a cathode heating current to flow and then opens to permit the lamp to strike. The starter circuit has a thyristor as the switch element, and a control circuit for rendering the thyristor conductive at a desired point during each cycle of the applied voltage. The control circuit includes means for increasing the instantaneous applied voltage which is required to trigger the thyristor with successive cycles of the applied voltage after switch-on of the circuit. This means preferably includes a capacitor which is progressively charged to provide an increasing bias which must be overcome by the applied voltage. If the lamp fails to strike, the required voltage for triggering goes on increasing until it is too high for the thyristor to trigger at all. No damage can then occur to the starter circuit or the lamp ballast.

Abstract: An energizing circuit for gas discharge lamps for room or street lighting or for lights used in document copying machines and the like comprises means for continuously energizing the same at a low non-useful light producing level when such lamps are not needed by a voltage which strikes an arc and maintains a low level of ionization with an infinitesimally small current and very little energy drain. This voltage may be an AC voltage or a DC voltage supplied by a unique circuit including a number of DC voltage sources, rectifiers, voltage adjusting and current-limiting impedances and electronic switches. The lamps are energized by AC or pulsating DC supplied by the aforesaid or other electronic switches operated at a high frequency of at least about 20-30 kilo-Hertz.

Abstract: The magnetron apparatus comprises a magnetron tube and a driving circuit including a transformer having a primary winding, a low voltage secondary winding for energizing the cathode filament of the magnetron tube and a high voltage secondary winding for applying an anode voltage upon the anode electrode of the tube. The high and low secondary windings and the terminals of the cathode filament are contained in a shield casing for preventing leakage of the wave.

Abstract: The invention relates to a relay starter for a discharge lamp wherein the lamp is stabilized by a series arrangement of at least an inductor and a capacitance. Also included in series with these stabilization elements and the lamp is an energizing winding of a relay having a normally-closed contact disposed in a circuit which shunts the lamp.A diode is also disposed in the circuit which shunts the lamp, so that if the lamp does not ignite, current flows for a short period of time through the diode which thereby charges the capacitor. When this capacitor has received a sufficient charge no further current flows either in the lamp circuit or in the shunting circuit so that the entire circuit is put out of operation.

Abstract: The present discharge lamp system comprises two or more serially connected discharge lamps connected across a pair of power input supply terminals through a ballast circuit and two or more serially connected semiconductor starter circuits. The starters are connected in parallel with their respective discharge lamps and have inherent breakdown voltages, whereby the total value of the breakdown voltages for each starter is higher than the source voltage at the power supply terminals. The system further comprises voltage dividing circuit elements enabling the conduction of one of the starters before the conduction of the other starter or starters in response to the source voltage, whereby the starters operate sequentially. At least one of the starters employs a backswing booster including a series circuit of a nonlinear inductor and a switching semiconductor and a capacitor connected in parallel with the series circuit to provide a sufficient starting voltage for the associated discharge lamp.

Abstract: There is disclosed an oscillator circuit for driving a fluorescent lamp, which comprises a power transistor having an emitter electrode connected to one terminal of a D.C. power source and a collector electrode connected to the other terminal of the D.C. power source through a primary winding of a transformer. A first secondary winding of the transformer is connected at its one end to the other terminal of the D.C. power source and at its other end to a base electrode of the transistor through one of a pair of filaments of the fluorescent lamp. A second secondary winding of the transformer is connected at its one end to the one filament of the fluorescent lamp and at its other end to the other filament of the fluorescent lamp to cause discharge in the fluorescent lamp.

Abstract: A fluorescent lamp fires more quickly at low temperature and its service life is lengthened if the input terminals of a full-wave rectifier are connected to the lamp electrodes and a resistor and capacitor are connected in parallel circuit between the output terminals of the rectifier. The voltage pulses applied to the electrodes prior to firing are reduced in peak amplitude and broadened by the improved circuit.

Abstract: A power source for operating gas discharge lamps and other loads at high frequency, typically utilizing a 120 volt ac source rectified to provide a 150 volt dc input and providing a 20,000 hertz output. An inverter with current feedback in place of the conventional voltage feedback providing voltage turn off and voltage turn on in less time and providing increased base current during the conduction time for reducing the voltage-current product and heat generated in the inverter. Voltage limiting and current limiting features are provided for the basic circuit. Inverter circuits with two transistors for increased loads are also provided.

Abstract: A circuit for the operation of fluorescent lamps which allows the current through the lamps to be raised above the manufacturer recommended limit without adversely effecting the lamps. Two oppositely poled diodes are connected to the two contact pins at each end of the lamps, and an AC voltage is applied thereto. The arrangement results in current through two properly poled diodes during one half cycle of the applied voltage, and through the two oppositely poled diodes during the second half cycle of the voltage. As a result of this alternate loading, the thermal stress in the lamp electrodes is substantially lowered, and the current through the lamp may be raised above the recommended limit. The AC voltage is preferably at a high frequency, for example twenty kilohertz, which results in illumination from the lamps originating along the glass walls due to the skin effect, and increases the illumination efficiency of the lamps.

Abstract: A circuit for the operation of fluorescent lamps which allows the current through the lamps to be raised above the manufacturer recommended limit without adversely effecting the lamps. Two oppositely poled diodes are connected to the two contact pins at each end of the lamps, and an AC voltage is applied thereto. The arrangement results in current through two properly poled diodes during one half cycle of the applied voltage, and through the two oppositely poled diodes during the second half cycle of the voltage. As a result of this alternate loading, the thermal stress on the lamp electrodes is substantially lowered, and the current through the lamp may be raised above the recommended limit. The AC voltage is preferably at a high frequency, for example twenty kilohertz, which results in illumination from the lamps originating along the glass walls due to the skin effect, and increases the illumination efficiency of the lamps.

Abstract: A pulse generator comprising an induction element, and a nonlinear condenser whose dielectric material portion is made of ferroelectric ceramics represented by a general formula of (Pb.sub.1-x-y, Ba.sub.x, Sr.sub.y)(Ti.sub.z, Zr.sub.1-z)O.sub.3.

Abstract: A starter for a discharge lamp including first and second filaments, comprises an SCR having an anode and a cathode connected in series through the first and second filaments and a ballast transformer to an AC power supply. The gate electrode and the anode of the SCR are connected to each other through a first resistor, while the gate electrode is further connected through a second resistor to the power supply side.

Abstract: The specification discloses a low loss ballast system for reducing the electrical power required to operate fluorescent and other ionized gas lamps as well as several unique starting and operating circuits which can be used in combination with conventional as well as the low loss system described herein.

Abstract: In the present magnetron operating circuit for generating microwave energy, the circuit components of the filter, the transformer and the rectifier are arranged within a shielded housing, in the same manner as the cathode input portion of a magnetron tube. A feed-through capacitor of the filter is arranged in the low voltage line of the transformer and secured to the wall of the housing to prevent undesired radiation. A coil with a ferrite core of the filter is preferably connected to the filament lead of the magnetron tube.

Abstract: A power supply for self-rectifying X-ray tubes controls filament current inversely to tube current. Although the tube current is passed only during alternate half cycles provision is made for symmetrical control of the filament current.

Abstract: A fluorescent lamp lighting device comprises a d.c. power source, a transistor, a transformer and a fluorescent lamp. The d.c. power source is connected in series with the primary winding of the transformer between a first electrode and a second electrode of the transistor. The fluorescent lamp has one filament connected to one end of a first secondary winding of the transformer. A second secondary winding of the transformer is connected between the other end of the first secondary winding of the transformer and the junction of the d.c. power source and the primary winding of the transformer. The fluorescent lamp has the other filament connected between the junction of the first secondary winding of the transformer and the second secondary winding and a third electrode of the transistor.

Abstract: A device for starting and operating a discharge lamp, in particular a low pressure sodium vapor lamp. The device comprises two input terminals connected by means of a coil and the primary winding of an auto-transformer with the lamp connected in series with a capacitor between the ends of the transformer secondary winding. In the operating condition of the lamp the core of the transformer becomes saturated. The lamp is shunted by an electronic starter which assists, in the operating condition of the lamp, in the restart of the lamp during each half cycle of the AC electric supply.

Abstract: A high frequency power supply with inductive coupling and a SCR starter to light two fluorescent lamps is described. It supplies high frequency square waves to the fluorescent lamp for improved light output, efficiency and stability of operation. The rectified line voltage from a full wave rectifier is fed via a SCR starter to two transistors that form an inverter circuit. The inverter circuit is coupled to a ferrite core autotransformer. The secondary windings of the autotransformer are used to heat the filaments of the electrodes of the fluorescent lamp, and to form a reactive coupling along with inductors for stabilizing the arc discharge of the fluorescent lamp.

Abstract: A device for starting a discharge lamp by means of a transistor starter provided with an auxiliary transistor for stopping the starting procedure if the lamp fails to ignite.A zener diode is included in the control circuit of the auxiliary transistor, a capacitor is connected in parallel across the lamp, and a self-inductor is included in the connection from the lamp to the main transistor. The auxiliary transistor has a second function in that, by the action of the zener diode, the auxiliary transistor delays the conduction of the main transistor so that a large rise of the voltage between the lamp electrodes is produced, which provides a more reliable ignition of the lamp within a large temperature range.

Abstract: A circuit for operating an electric discharge lamp wherein a change in the mode of operation of the circuit is effected in response to a change of phase of a voltage or current in the circuit which occurs during operation e.g. when the lamp strikes or as the lamp runs up to full current.

Abstract: A ballast for a rapid start fluorescent lamp with heated filaments has a secondary winding supplying lamp current, tertiary windings for supplying heater current to the filaments, and solid state switching circuits in secondary circuits through the filaments. Each switching circuit, which may be integrated with the ballast circuit or connected to a filament within the lamp envelope, comprises two voltage divider resistors having a common junction coupled to the gate of a triac whose primary electrodes are connected in parallel with the voltage divider. The triac is in series with the filament and supplies heating current to the filaments prior to lamp starting. When the lamp starts and conducts rated operating current the voltage divider reduces the voltage at its junction and at the triac gate below triac breakdown level thereby substantially eliminating heater current.

Abstract: The invention relates to a mixed-light lamp. According to the invention the lamp is connected to a cascade circuit of two capacitors and two diodes. The increase in voltage obtained with that cascade circuit is fed to an auxiliary electrode of the discharge tube of the mixed light lamp.All electric circuit element of the device are located within the lamp. The lamp described is particularly suitable to be operated by an AC mains circuit of a relatively low voltage.

Abstract: A circuit employing an oscillator having a feedback loop for supplying operating current at a frequency in the range 20-25 kilohertz to a pair of fluorescent lamps connected in series. The heater filament of the first lamp is made a series element in the feedback loop of the oscillator, so that removal of that lamp disables the oscillator. Switching means is provided to bypass the open socket terminals of the second lamp when it is removed from its sockets, permitting power to continue to be supplied to the first lamp.

Abstract: A system providing flickerless operation of a gaseous discharge lamp utilizes a DC voltage applied across the lamp electrodes. Low starting voltage and power consumption are obtained by applying an AC voltage across a grounded conductor member and adjacent lamp electrodes. This is a division of application Ser. No. 443,825, filed Feb. 19, 1974, now U.S. Pat. No. 3,890,540.

Abstract: A discharge lamp (e.g., fluorescent lamp) lighting apparatus using as the starting element a sintered type oxide resistance element having the voltage-current characteristic that the element is rendered conductive when impressed with an inter-electrode voltage applied at the discharge lamp starting time and rendered substantially non-conductive while impressed with an inter-electrode voltage applied during lighting of the discharge lamp. The discharge lamp lighting apparatus using in particular a sintered type oxide resistance element comprising ZnO, MgO and MnO.sub.2 as the starting element presents an excellent performance.

Abstract: The invention relates to an ignition circuit for a sunlamp, the lamp including a gas or vapor discharge tube which emits ultraviolet radiation and two infrared radiators.The ignition or auxiliary circuit uses a diode which supplies a succession of current pulses which flows through a heating resistor in the discharge tube for the purpose of ignition. Relatively high voltages between the electrodes of an electric discharge tube, for example, this discharge tube can be realized.

Abstract: A solid state starter apparatus for a discharge lamp comprises a current limiter, an AC power supply, a discharge lamp of filament-preheating type and a switching circuit for controlling the turning on and off of the discharge lamp. The switching circuit further includes a lightedstate detector circuit for detecting the turning on or off of the discharge lamp, a current breaker circuit controlled by the lighted-state detector circuit to cause the filament current to be turned on and off, and a preheater circuit for starting to supply a filament preheating current in accordance with the magnitude of the current controlled by the current breaker circuit.

Abstract: A voltage producing device comprises a circuit in which an AC power source, a coil and a first capacitor connected in series. A unidirectional triode semiconductor switching element is connected across both terminals of the capacitor, a voltage limiting semiconductor element is connected to a gate electrode of the switching element, and a charging-and-discharging circuit including a second capacitor is connected to a cathode of the switching element.

Abstract: In the system disclosed, a transformer connected to an alternating power source establishes a continuous alternating output voltage which is connected directly across a gas discharge lamp to apply the voltage continuously across the lamp. The transformer output voltage is set within a range which includes a condition that causes the lamp to exhibit a positive impedance value when the lamp is discharging. The transformer and the source together exhibit an impedance substantially less than the impedance value of the discharging lamp.

Abstract: A power supply circuit for a microwave oven which includes a magnetron, a transformer, a plural capacitor, and a current rectifier. The power supply circuit is particularly adapted to provide constant power output from the magnetron using either a 50Hz or 60Hz input power by selecting an appropriate one of said plural capacitances.

Abstract: A television receiver includes a switched-mode power supply driven by the horizontal oscillator and driver section of the television receiver. An on/off switch for the receiver is connected to the switched-mode power supply to vary its output according to the setting of the on/off switch. This output, when the switch is "on", is used to supply full operating potential to the cathode ray tube filaments and operating potential for some of the portions of the television receiver. When the on/off switch is in its "off" position, it operates to cause the power supply to supply reduced or standby potentials to those same portions of the receiver and to the cathode ray tube filaments. At the same time, other portions of the receiver are turned off and on in the normal fashion.

Abstract: An electric discharge lamp lighting circuit in which a discharge lamp is lighted by a circuit comprising a semiconductor switching circuit in which the cathode of a first thyristor is connected to the gate of a second thyristor and the first and second thyristors are commonly connected at the respective anodes, an integration circuit consisting of a capacitor and a resistor and connected between the gate of the first thyristor and the cathode of the second thyristor, a resistor connected between the integration circuit and the anode of the first thyristor, and a resistor connected between the gate and cathode of the second thyristor.