Abstract: An electronic ballast circuit for a lower pressure lamp wherein a voltage divider network coupled by a capacitor and directly coupled to an AC source is shunted by a series connected transistor switch and capacitor filter, and the switch is coupled by a diode to a lamp while a ballast resistor couples the filter capacitor to the lamp. A starter network device includes a glo-bottle starter which couples a transistor switch to the lamp with a resistor coupled to the glo-bottle starter and the transistor switch.

Abstract: A circuit arrangement for operating a high-pressure gas discharge lamp (14) with high frequency current in which a direct voltage is supplied to a transistor bridge (5 to 8) having a transverse branch in which is arranged a choke coil (13). The clock (switching) frequency of the transistor bridge is varied within each period of the AC mains alternating voltage in dependence upon the current derived from the AC mains voltage.

Abstract: In a circuit for the operating of gas discharge lamps in which a starting circuit (2, 17) having a starter transformer (17) and a source of auxiliary voltage which can be disconnected after starting has been effected are provided for the starting of the lamp, there is provided a full-wave rectifier (6) with which a charging capacitor (10) and a voltage-dependent electronic switch element (8) are connected in parallel. A switch contact (9) which is in series with the charging capacitor (10) can be actuated by the switch element (8). The charging capacitor (10) which supplies the operating voltage for the gas discharge lamp (3) can be charged to a voltage which can be selected by means of the switch element (8). The full-wave rectifier (6) which serves a source of auxiliary voltage can be disconnected by means of a control element (4) from the gas discharge lamp (3) after the latter has been started.

Abstract: An electronic ballast for energizing fluorescent lamps comprising a converter including a rectifier and a filter for converting an alternating source voltage into a direct current voltage, a network including first and second switching transistors, a tank circuit having a primary winding of a transformer, a secondary winding of the transformer for providing feedback of a portion of the voltage developed across the tank circuits and a bias circuit coupled between the opposite ends of the secondary winding and the emitters of the transistor for alternatively applying bias to the transistors, the network serving to convert a direct current voltage into an amplified sinusoidal voltage having a high frequency, and fluorescent lamps connected in a series configuration coupled across the primary winding.

Abstract: A fluorescent lamp ballasting means comprises a conventional voltage doubler, which voltage doubler is adapted to operate from a regular power line AC input voltage and to supply a unidirectional output current to the fluorescent lamp. After the lamp has been started, the resulting lamp current is determined in part by the size of the capacitors used in the voltage doubler and in part by the impedance of an impedance means connected in series between the lamp and the voltage doubler.By choosing the magnitude of the voltage doubler capacitors such as to constitute the major lamp-current-determining factor, a relatively good overall systems efficacy is obtained.Lamp starting is aided by capacitively coupling the input AC voltage to the lamp in a fashion additive to the DC voltage provided by the voltage doubler--this DC voltage being coupled to the lamp by way of a rectifying means. As a result, the peak lamp starting voltage is equal to four times the peak voltage of the input AC voltage.

Abstract: A ballast circuit for direct current gaseous electrical discharge devices includes a rectifying bridge, and an inductive ballast for storing excess energy. The rectifying bridge uses a pair of thyristors which must be gated on for the bridge to supply rectified voltage to the inductor and device. Gating is delayed at the beginning of each half-cycle to allow the inductor to discharge most of its stored energy.

Abstract: Supply device for a flash tube comprising a capacitor, a d.c. voltage source connected to the capacitor, an energy switch located between the capacitor and the flash tube, a circuit able to emit a control pulse for the said switch and a preionization circuit for the flash tube, wherein the preionization circuit comprises a second energy switch connected to the capacitor across a variable resistor, as well as to the flash tube, and a second circuit able to emit a control pulse for the second switch, said second pulse being in advance of the first pulse.Application to the optical pumping of lasers.

Abstract: A starting circuit for discharge lamps includes a current limit device, a full wave rectifier circuit and a Cockcraft-Walton's circuit which are connected between a d.c. discharge lamp having a cathode and an anode and the input terminals of an a.c. power source. Moreover, the Cockcraft-Walton's circuit is constructed by sharing a rectifier with the full wave rectifier circuit and a preheating circuit is provided for the cathode and includes another rectifier of the full wave rectifier circuit and a switching device.

Abstract: A low pressure metal vapor discharge lamp has a double-tube type discharge vessel consisting of a fully closed outer glass bulb and an inner glass tube substantially coaxially disposed in the outer glass bulb, the inner glass tube being closed at its fixed end and opened at its free end. The space within the discharge vessel is filled with a small amount of a metal and a rare gas of a low pressure. A single cathode is disposed within the space inside the inner glass tube, while a plurality of anodes are disposed in the annular space between the inner glass tube and the outer glass bulb. According to the invention, a number of discharge channels corresponding to that of the anodes are formed between the single cathode and respective anodes, via the opening end brim of the inner glass tube. In operation, anode oscillations take place alternately in respective anodes to cause a self-excitation switching operation, so that a plurality of plasmas are formed.

Abstract: A discharge lamp firing apparatus is disclosed which includes providing only the necessary firing voltage to the lamp prior to the firing thereof. As such, the surrounding system is not subjected to transients caused by conventional mechanisms which suddenly switch an extremely high voltage across the lamp. As a result, the present apparatus protects the associated circuitry as well as prevents needless overvoltage conditions to the lamp.

Abstract: An electronic ballast employs an electronic inverter which drives a main power transformer across the output of which terminations are connected for a plurality of fluorescent lamps. A high impedance capacitor is connected in parallel across at least one and less than all of the fluorescent lamps. An auxiliary transformer is interposed between the output of the main power transformer and the cathode elements of the fluorescent lamps. Upon start-up, the high impedance capacitor initially creates a bypass around lamps with which it is connected in parallel to thereby apply the entire high voltage output of the power transformer to start the remaining lamps. Once these lamps are started the voltage drop thereacross is reduced to allow the high voltage output to bypass the high impedance capacitor and start the lamps connected in parallel therewith. The auxiliary transformer provides good magnetic coupling and low voltage to the cathode elements of the fluorescent lamps.

Abstract: A power supply for an ac discharge lamp utilizes a switching transistor for turning on and off the dc current from a dc power circuit. The dc current is then fed to a low pass filter for supplying the dc power to the lamp with alternating polarity. A voltage and a current sensing circuits effective to control the dc power to a substantially constant level is connected to a control circuit for controlling the on and off times of the switching transistor. In such a power supply, the voltage and current sensing circuits are made up of transformers whereby the high-voltage circuit section is effectively separated and insulated from the low-voltage circuit section so as to prevent any possible electrical shocks.

Abstract: A method and circuit for operating an incandescent lamp are disclosed in which the operating voltage applied to the lamp alternates in a regular and abrupt manner between forward and reverse polarities. The magnitude of the voltage is substantially the same for the two polarities and, therefore, the luminosity of the lamp is substantially constant. However, lamp life is increased as compared to standard DC operation since the alternating polarity of the operating voltage reduces the rate at which the lamp fails due to lamp filament breakage.

Abstract: At least one high intensity discharge lamp is utilized in the growing of plants within a growth chamber. The lamp is connected to a power supply that provides pulses of alternating polarity to the lamp through a ballast which first provides a relatively high inductance and which after lamp current has reached a certain level provides a matched T-configured impedance network. Initially, a microprocessor, there being one for each lamp ballast (or one for a group of lamps), closes a switch to connect the lamp to the power supply through a step-up transformer, the secondary winding of which during start-up contributes to the high impedance condition during the early stage of lamp operation and which is thereafter part of the T-network. When the lamp is ionized, both the lamp current and the lamp voltage are sensed.

Abstract: An energy conserving lighting system is provided wherein a plurality of fluorescent lamps are powered by a poorly regulated voltage source power supply which provides a decreasing supply voltage with increasing arc current so as to generally match the volt-ampere characteristics of the lamps. A transistor ballast and control circuit connected in the arc current path controls the arc current, and hence the light output, in accordance with the total ambient light, i.e., the light produced by the lamps together with whatever further light is produced by other sources such as daylight. In another embodiment, a transistor ballast is utilized in combination with an inductive ballast. The transistor ballast provides current control over a wide dynamic range up to a design current maximum at which maximum the transistor is saturated and the inductive ballast takes over the current limiting function.

Abstract: An apparatus for a gaseous discharge lamp includes a power controlling device for converting an AC voltage into a phase control output, a high frequency generating device for converting the output of the high frequency generating device into an high frequency output and a discharge lamp which is lighted by the output of the high frequency generating device and whose filament is heated. The high frequency generating device includes a DC power source for supplying a DC voltage to the power controlling device whenever the power controlling device remains to generate the phase control output. The output of the DC power source heats the filament of the discharge lamp for a period during which no phase control output is produced.

Abstract: An electronic ballast circuit for powering a plurality of fluorescent lamps or the like from an unsmoothed DC voltage source includes a sine wave converter operatively connected to receive said DC voltage, for generating a high frequency alternating voltage of sufficient amplitude to power said lamps. The converter comprises a tank circuit and two push-pull transistors connected thereto and a current source capacitively coupled to said tank circuit for providing base drive alternately to each transistor. A lamp filament heater current cancellation circuit reduces power drain once the lamps have turned on.

Abstract: An improved solid-state fluorescent lamp ballast circuit in which rectified line voltage is chopped, utilizing high power field effect transistors, to provide a high frequency input to a fluorescent lamp, thus permitting smaller reactive components to be utilized. Also shown is circuitry whereby the duty cycle of the chopping switches may be modulated to permit dimming of the lamp, which may be remotely located.

Abstract: A flash tube is provided for producing successive high intensity bursts of light, and a pulse producing device is provided for supplying a train of high voltage pulses for energizing repeatedly the flash tube. An impedance matching arrangement is provided and includes a first unidirectional device which couples the output of the alternator to the pulse producing device for energizing it periodically during half cycles of the alternating current output of the alternator. The arrangement also includes a second unidirectional device which the output of the alternator to an auxiliary lighting device to energize it during alternate half cycles of the alternator. As a result, the alternator supplies lower instantaneous current to both loads at a favorable operating characteristic of the source.

Abstract: An operating circuit and method for efficiently operating and starting an electrodeless lamp having a magnetic core operated at radio frequencies. The circuit generates a current which flows through the winding of an electric field inducing means in the lamp in a reverse-bias direction, with respect to a drive current, to operate the core of the inducing means in all quadrants of the B-H curve, with the time average of all current through the lamp winding equaling approximately zero in order to avoid or minimize heat energy losses and sharp current peaks caused by saturation. This also allows use of lower current-capacity less-expensive components. The circuit repetitively applies constant-current DC drive pulses to the lamp winding for a small percentage of an interval during which energy is stored, which is used to generate the reverse-bias current.

Abstract: A light regulation system is provided wherein the light output of a fluorescent lamp(s) is regulated in accordance with the RMS value of the lamp arc current which is automatically adjusted to maintain a referenced ambient light level or arc current. The ballast and associated lamps of the system receive the full line voltage until the lamps are ignited and thereafter the current thereto is automatically limited by limiting the amplitude of the ballast current during the part of each AC voltage half wave that the lamps are ignited. Control between the minimum light level, wherein a minimum arc current flows during each half cycle, to the maximum light level is accomplished by permitting the minimum arc current which flows during the "lamps on" period of each half wave to increase to maximum arc current over a part or all of the period of each half wave that the lamps are on.

Abstract: A solid state power switch for gas discharge lamps is disclosed which is capable of providing a bipolar signal to a lamp and which substantially eliminates losses due to switching delays of internal devices. A timing control signal of a predetermined frequency and wave shape is provided to a pair of threshold comparators, which respectively receive a first and second threshold signal such as first and second reference voltages. The first comparator produces an output signal only when the timing control signal is below the first threshold signal and the second comparator provides an output signal only when the timing control signal is above the second threshold signal. The signals from the two comparators are used to control the on time of power switches of opposite polarity. Thus, the time that the control signal is between the two thresholds represents the switching delay interval.

Abstract: A cathodoluminescent lamp for use for general lighting service includes an anode constituted by an electrically conducting coating, which may be partly internally reflective, on the interior surface of the bulb wall, a phosphor coating over the whole of the bulb wall interior, a dome-shaped metal mesh grid located near the junction of the bulb with the envelope neck and supported on a hollow metal cylinder, and an electron emissive cathode mounted within the grid/cylinder assembly. The cathode may be a "wreath" filament or indirectly heated disc located near the grid, or a linear filament located near the open end of the cylinder remote from the grid. In the latter case a metal disc, connected to the negative lead to the cathode, is located near the open end of the cylinder, to repel electrons emerging therefrom. A circuit, which may be incorporated in the lampholder, converts the supply to unidirectional operating voltages applied to the anode, grid and cathode.

Abstract: A circuit for starting and ballasting a compact high intensity arc discharge lamp, and for preventing failure of the arc discharge. A filament connected in series with the arc lamp provides illumination during arc start-up and functions as a ballast during normal arc operation. An oscillatory starting circuit supplies starting voltage to the arc lamp until an operating arc is established. The circuit includes a "keep-alive" feature which prevents the arc from extinguishing during power fluctuations.

Abstract: A low pressure metal vapor discharge lamp has a double-tube type discharge vessel consisting of a fully closed outer glass bulb and an inner glass tube substantially coaxially disposed in the outer glass bulb, the inner glass tube being closed at its fixed end and opened at its free end. The space within the discharge vessel is filled with a small amount of a metal and a rare gas of a low pressure. A single cathode is disposed within the space inside the inner glass tube, while a plurality of anodes are disposed in the annular space between the inner glass tube and the outer glass bulb. According to the invention, a number of discharge channels corresponding to that of the anodes are formed between the single cathode and respective anodes, via the opening end brim of the inner glass tube. In operation, anode oscillations take place alternately in respective anodes to cause a self-excitation switching operation, so that a plurality of plasmas are formed.

Abstract: A converter circuit for use in changing a series wired primary ballast normally employed for operating a mercury vapor lamp to a more energy-efficient high intensity discharge lamp, such as a high pressure sodium lamp, with the circuitry involved incorporating the series type ballasts that usually have operating characteristics for operating a 400 watt and a 175 watt lamp, with the secondary of each ballast comprising isolated neutral secondary winding. These are primary loop series wired ballasts which are controlled by regulators of a constant current type and dimensioned for operating at a 2400 volts ac open circuit voltage class functioning at 60 Hz.

Abstract: A circuit for starting and ballasting a compact high-intensity arc discharge lamp. A filament connected in series with the arc lamp provides illumination during arc start-up and functions as a ballast during normal arc operation. An oscillatory starting circuit includes a transformer and a frequency-controlling ringing circuit, and applies starting voltage to the arc lamp until an operating arc is established. The circuit includes capacitor means for isolating the starting transformer from the operating path of the arc lamp, and further includes a voltage-doubling starting circuit and also a "keep-alive" feature which prevents the arc from extinguishing during power fluctuations.

Abstract: The invention relates to a mixed light lamp arrangement intended to be connected to an a.c. power supply. The lamp arrangement comprises a rectifier bridge having output terminals interconnected by the mixed light combination consisting of a series arrangement of an incandescent filament and a discharge tube. The series arrangement is shunted by a branch comprising a capacitor and an anti-parallel arrangement of a diode and a thyristor with the thyristor being rendered conductive just prior to the end of each half cycle of the a.c. power supply. This results in a mixed light lamp wherein the capacitance of the capacitor can have a relatively low value and the luminous efficacy can be relatively high.

Abstract: First and second rectifiers (37), (41) have inputs connected to an A.C. power source (12) through a unitary switch (33) and outputs connected to first and second smoothing filters (38), (42) respectively. An inductance (39) is connected between the switch (33) and the first rectifier (37) whereas a capacitance (43) is connected between the switch (33) and the second rectifier (41). The values of the inductance (39) and capacitance (43) are selected in such a manner that surge currents through the capacitance (43) and inductance (39) occuring when the switch (33) is closed are limited and the power factor of the power supply (31) is maximized.

Abstract: A high-voltage power supply for an electron-beam gun with a heatable cathode and an anode and of the type having an electronic switch connected in the current circuit for the cathode and controllable for blocking the current to the cathode, includes an impulse protecting filter connected in the current circuit for the cathode. The filter comprises a capacitor connected in parallel to the cathode, a choke connected in series with the cathode current circuit, a blocking diode and a discharge resistor connected in series therewith, with the diode and resistor connected in parallel with the choke.

Abstract: A spark source circuit has a discharge circuit including reactive means connected in circuit between a capacitor and an analytical spark gap and switching means for effectively removing the capacitor from the discharge circuit after an initial flow of current through the spark gap so that the current flow through the spark gap is essentially unidirectional. At the start of the capacitor discharge, the discharge circuit is essentially of the classical RLC oscillatory discharge type; and the switching action converts the discharge circuit to essentially a classical RL discharge type circuit for the remainder of the spark discharge. The circuit is simple and efficient, permits use of ceramic capacitors, and may be housed in a sealed enclosure.

Abstract: A traffic light control circuit of the type utilizing solid state thyristor switches with their control terminals driven by a diode bridge trigger network that includes switches for selectively interrupting one or both legs of the trigger network for energizing the traffic lights with either full wave power for normal daytime operation or half-wave power for night time operation at reduced brightness, thereby providing power savings for night time operation.

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: A solid state ballast circuit for a discharge lamp includes a transistor oscillator with a current amplifier connected to a transformer one secondary winding of which is connected to the lamp and another secondary winding of which is coupled to the amplifier input. An inductive choke coil is connected in the power circuit of the amplifier so that when the lamp burns out or is removed the operating frequency increase resulting from the decrease in load circuit capacitance results in an increase in impedance of the choke, drastically reducing current flow through the amplifier power circuit to prevent transistor damage or RF interference radiation. The current amplifier disclosed is a two-stage emitter follower circuit.

Abstract: A D.C. power supply energized directly from an A.C. source including a voltage doubler circuit supplied with current from the A.C. source via a gate controlled bidirectional switch with the gate circuit for the bidirectional switch connected for control by a disabling switch means. The disabling switch means is controlled by a voltage level sensing circuit that senses the output voltage of the voltage doubler circuit to cause operation of the disabling switch means to disable the gate circuit for the bidirectional switch when a predetermined voltage level is sensed by the sensing circuit.

Abstract: A fluorescent lamp having a plurality of columns positioned in a generally uniform manner within the lamp envelope, each column having an electron emissive cathode mounted therein connected to a cathode leadwire. An anode member connected to an anode leadwire extends to the upper portions of each column. A conductive starter member is mounted within each column so as to provide a first gap between one of its ends and the cathode and a second gap between the other of its ends and the associated anode extension. A D.C. voltage is applied to the anode and cathode leadwires, the D.C. voltage being obtainable from an external A.C. source via a suitable voltage rectifier/multiplier circuit which is positioned within the re-entrant stem member of the lamp.

Abstract: The present application discloses a circuit for improving the efficiency of energy consumption, extending lamp life, and facilitating the starting and steady state flickerless operation of a discharge lamp normally utilizing a source of alternating current, such circuit including: (a) a full wave rectifier connected between both an input set of terminals and an output set of terminals, the input set comprising the AC line input leads and the output set comprising the positive and negative supply leads of the lamp; (b) a voltage-raising capacitance disposed between one terminal of the AC input and one or both terminals of the rectifier output; and (c) a filtering means connected between the positive and negative output of said full wave rectifier, wherein the output of the voltage-raising capacitance is applied across the filtering means, thereby providing a no-load voltage at the output leads which is approximately equal to (2.sqroot.2) .sup.E input (rms).

Abstract: A flow, or rotary type, microfilm recording apparatus for filming documents having a document transport means to move documents past an aperture area. An alternating current powered fluorescent lamp is employed for illuminating the documents in the aperture area. In order to adjust, set and maintain a substantially constant level of illumination in the aperture area and to reduce flicker, a lamp regulator circuit is provided which includes a shunted rectifier load circuit and a variable current device responsive to the illumination from the fluorescent lamp for varying the voltage drop across the shunt in accordance with the illumination.

Abstract: A dc to ac inverter for operating a gaseous discharge lamp through pre-ignition, arc stabilization, warm-up and final run states is disclosed. The arrangement comprises a transformer and a pair of transistors connected for alternate conduction in a self-oscillating configuration in which turn off occurs at a predetermined flux level in each conduction period. The flux limit is used to preclude excess current drain during warm-up when the lamp resistance is at a minimum. A capacitor is provided, resonant at a harmonic of the inverter output waveform for producing the enhanced output voltage required for pre-ignition. The capacitor also helps to maintain a higher harmonic content during warm-up, enhancing the effective ballasting reactance during that period in relation to that during final run operation. A shift of the oscillating frequency of the inverter from pre-ignition to final run operation further enhances inverter operation.

Abstract: Electrical power is converted into rectangular waves, which are loosely coupled to a fluorescent lamp. A parallel tank circuit resonant near the fundamental or a harmonic of the square wave frequency is connected between the electrodes of the lamp. The electrodes of the lamp each have a pair of terminals across which an electrical potential is applied to heat the electrodes while starting the lamp. Power is applied across the first and second electrodes while starting the lamp and after starting the lamp. Power is also applied and/or the pair of terminals of the second electrode while starting the lamp and after starting the lamp. The ratio of voltage across the first and second electrodes to the voltage across the pair of terminals is such as to properly preheat the electrodes and prevent arcing between each pair of terminals, and arcing between the first and second electrodes while starting.

Abstract: A lighting inverter for operating an electrical discharge lamp from a direct current power source. The inverter includes a resonant feedback inverter which converts the output of the d.c. power source to an alternating current output and regulates the a.c. inverter output voltage level by varying the frequency thereof. A ballast filter is coupled to the regulated output of the resonant feedback inverter and is formed by a series circuit of a ballast inductor and a ballast capacitor. Connected across the capacitor is the discharge lamp. Appropriate circuit parameters such as ballast inductance, ballast capacitance, inverter operating frequency, and the inverter resonant frequency are selected to maintain almost unity power factor at the input to the ballast filter.

Abstract: An integrated circuit chip containing one or more light-emitting diodes is mounted within a light-diffusing encasement having a standard incandescent light bulb lamp base. The integrated circuit chip also contains a rectifier and voltage regulator circuit. The resulting solid state lamp may then be used to replace any standard incandescent light bulb, as it can be inserted in any existing standard A.C. or D.C. lamp sockets. The encasement may be a standard hollow light bulb, or, for maximum light diffusion, a solid transparent or translucent plastic in which the chip is embedded.

Abstract: A starting circuit suitable for sodium vapor street lamps is disclosed. The circuit includes a voltage doubler which periodically fires pulses through the lamp ballast. The pulsing is controlled by a neon lamp connected to a gate anode of a triac. When the triac fires the capacitors which form the voltage doubler are shorted across to produce the starting pulse.

Abstract: An electronic ballast circuit includes a directly driven high frequency inverter circuit with a series resonant output circuit coupled to a load circuit having a high intensity discharge (HID) lamp and to a drive circuit dependent upon current flow in the load circuit. A starting circuit for the high frequency inverter is coupled to a DC source and to a charge storage and isolating circuit and provides initial energization to the high frequency inverter circuit. Also, a lamp starting circuit initiates increased conductivity of the high frequency inverter circuit which causes development of energy sufficient to "fire" an HID lamp whereupon a disablement circuit essentially removes the lamp starting circuit from the operational circuitry.

Abstract: A power circuit for a discharge lamp, in particular a flash lamp serving as light source in an optical analysis apparatus which comprises an electric power source outputting a d.c. voltage and capable of reabsorbing electrical energy, which also comprises an energy transferring circuit inserted between the electric power source and a first capacitor connected to the lamp, the capacitor being charged via the energy transferring circuit and adapted to store the energy required for each discharge across the lamp, the energy transferring circuit comprising a first current path comprising the primary winding of an autotransformer and adapted to transfer current from the electric power source to the first capacitor until the voltage across it reaches a predetermined value, and a second current path comprising a second capacitor for storing part of the surplus or non-used energy stored in the autotransformer during the charging of the first capacitor.

Abstract: Direct current ballasting and starting circuitry for efficiently operating a gaseous discharge lamp on direct current. Series-pass switching means in one of a pair of input lines alternatively switches between on and off states to periodically supply pulses of energy from a source of direct current voltage. During steady-state operation, current sensing means limits the maximum current conductable by said switching means such that the output of the circuitry is current regulated. Starting means, in series connection between the filter means and an output terminal, senses the nonionized state of the lamp and provides a voltage pulse of sufficient magnitude and duration to initiate ionization in the lamp. Various forms of control means or drive means for controlling the conductive state of the switching means are disclosed.An A.C. to D.C.

Abstract: A direct drive electronic ballast circuit suitable for a fluorescent lamp load includes a high frequency oscillator inverter circuit having a tuned output circuit coupled to a load and to a drive circuit series connected to the load and dependent upon current flow therein. The high frequency oscillator inverter circuit is also coupled to a pulsed DC potential source which is shunted by a charge storage and isolating circuit energized by a feedback rectifier circuit which supplies energy whenever the potential from the pulsed DC potential source decreases below a given reference level. A relaxation type oscillator is coupled to the high frequency oscillator inverter circuit and provides a starting capability therefore.

Abstract: An electronic ballast circuit includes a direct drive high frequency inverter circuit with a tuned output circuit and a drive circuit dependent upon current flow in a load circuit. The high frequency inverter circuit is coupled to a DC potential source which is derived from a pulsed DC potential source by way of a charge storage and charge isolating circuit. An oscillator provides a starting capability for the high frequency inverter circuit and is essentially removed from the active circuitry upon energization of the high frequency inverter circuit.

Abstract: Circuit for providing low ripple DC power supply from a single-phase AC source without the use of a filter capacitor. The circuit comprises a high leakage reactance transformer with a primary winding and two secondary windings arranged with the secondary windings on opposite sides of the primary winding, a leading current circuit connected to one secondary winding and a lagging current circuit connected to the other secondary winding, and a three-phase full wave rectifier bridge connected to the leading and lagging current circuits to provide a low ripple DC power output. The DC power supply circuit is used with a pulse generating circuit to provide pulsed operation of a gaseous discharge lamp such as a high pressure sodium vapor lamp, and produces desirable relationship of lamp watts to lamp volts for improved lamp life and uniformity of illumination.

Abstract: A starting device for a gas discharge lamp, to whose electrodes AC voltage is applied, comprises:a. first means electrically connected with at least one lamp electrode to apply to the lamp a transient voltage pulse which initially changes in amplitude in a polarity direction relatively in opposition to the polarity of the main voltage simultaneously supplied to the electrodes,b. said first means including circuitry to cause said pulse to thereafter change in amplitude in a polarity direction in aid of the polarity of the main voltage simultaneously supplied to the electrodes.