Abstract: A flashlamp pumped laser is controlled to emit a series of narrow pulse width laser pulses in quick succession. A control circuit associated with the flashlamp receives firing signals of limited pulse duration and serves to ignite and extinguish the flashlamp in accordance with the leading and trailing edges of a single firing signal pulse. The laser generates a coherent light pulse corresponding to the pumping flashlamp pulse. The flashlamp control circuit includes a main capacitor which stores electric charge sufficient to provide current to the flashlamp for several pulses in succession. The circuit also includes a trigger capacitor which supplies current through a transformer coupled to the flashlamp to initiate current conduction therein.

Abstract: A new and improved electronic control module (ECM) for controlling lighting functions of an incandescent light bulb and method of manufacturing the ECM. The ECM is installed, such as by press fitting into a dielectric insulating material at the socket end of the bulb, after the high temperature bulb fabrication steps have been completed. In this manner, the solid state and associated circuitry of the electronic control module are not subjected to the high temperature processing used in lamp bulb fabrication. The electronic control module is especially well suited and adapted for integration into the lamp bulb housing and is constructed using a minimum number of reliably constructed and connected electrical components in a hybrid-type circuit module assembly which is economical to manufacture.

Abstract: A fluorescent lamp power control having an input conditioning section, a lamp driver section, and a power command interface and control section to control power to fluorescent lamps. An external power command input is compared to an internally generated, computed power level and an electronic preregulator is controlled to regulate amp power. The preregulator output voltage and lamp driver current are multiplied to obtain a signal indicative of lamp power. A power command interface isolates the external power command input. Fluorescent lamp dimming is achieved by reducing the external power command input signal, reducing the power delivered to the fluorescent lamps.

Abstract: A low pressure discharge lamp apparatus has a low pressure discharge lamp with an arc tube. The arc tube has a first end and a second end, each with electrodes which define a discharge space therebetween. A mercury/rare gas is sealed in the arc tube. The low pressure discharge lamp apparatus further has a lighting circuit apparatus for lighting the lamp by supplying a current with a polarity reversed for each half cycle to electrodes in the first and second ends of the arc tube. The lighting circuit apparatus supplies, to the lamp, a current whose waveform has a flat peak for each half cycle and a maximum current value of the current is restricted to less than a level in which the excitation of mercury atoms is saturated.

Abstract: An apparatus for operating discharge lamp. The apparatus includes a source of electrical power, switching devices for switching the electrical power, a control circuit for controlling the switching devices, a transformer having a primary winding for receiving the electrical power switched by the switching devices and a secondary winding for supplying power to the lighting apparatus, a resonant circuit including an inductor and a capacitor for regulating the frequency of the electrical power and a circuit for powering the control circuit, the powering circuit including a secondary winding on the inductor and an additional winding on the transformer connected in a differential manner.

Abstract: The actuator is connected in series between the power supply and the flashing light. It includes a switch which is connected in series between the power supply and the flashing light so that when the switch is closed the light turns on and when the switch is open the light is turned off. A comparator controls the opening and closing of the switch at a frequency determined by an RC timer. Also, the duty cycle of the flashing light is controlled by the timer. A current overload protector lowers the duty cycle of the flashing light as the magnitude of the overload is increased and, in the event of a short circuit, decreases the duty cycle to approximately zero.

Abstract: In flashing light warning apparatus of a type having a voltage source (U), a main blocking transformer (HW), a flash tube (R), an ignition device (Z), a first and a third storage condenser (K1, K3), and an electrical switching device (S1), a switching path of the first electrical switching apparatus is arranged parallel to the first storage condenser, the third storage condenser and the ignition device are coupled to an auxiliary blocking transformer (ZW), and the first switching device can be switched by a control device (B). Such a flashing light warning apparatus can be produced in an uncomplicated, cost effective manner, to provide light energy which can be changed during operation to provide a day flash and at least one type of night flash. The night flash is at such a level that its output can be recognized from afar only by night vision apparatus.

Abstract: The combination of a fluorescent lamp with a grid between its electrodes and control equipment for operating the lamp in an on condition and an off condition by the application of pulses to the grid.

Abstract: An incandescent light bulb or the like and process for manufacturing same wherein an electronic control module (ECM) is installed, such as by press fitting into a dielectric insulating material at the socket end of the bulb, after the high temperature bulb fabrication steps have been completed. In this manner, the solid state and associated circuitry of the electronic contorl module are not subjected to the high temperature processing used in lamp bulb fabrication. The electronic control module is especially well suited and adapted for integration into the lamp bulb housing and is constructed using a minimum number of reliably constructed and connected electrical components in a hybrid-type circuit module assembly which is economical to manufacture.

Abstract: A light string controlling apparatus includes a bridge rectifier, an RC filter, an signal generator, and a silicon controlled rectifier. The signal generator provides the gate of the silicon controlled rectifier a train of pulses or analog signals or a combination of pulses and analog signals, to control the conducting angle of the silicon controlled rectifier, affecting the flashing frequency and illumination of a light string.

Abstract: A self contained battery operated table lamp for use in restaurants, and the like. The lamp includes an electric light which is energized on an intermittent basis by a switching circuit to assure long battery life. A feed back loop is included in the switching circuit for establishing the duty cycle of the energizing power intermittingly applied to the lamp. A flicker signal generator is connected to the energizing circuit of the light to introduce a flicker into the output of the light. The flicker signal generator incorporates a plurality of independent oscillators, each operating at a slightly different frequency. The outputs of the various oscillators are summed in a summing network with each being given a slightly different weighting factor, and the resulting signal is injected into a feedback loop to modify the average voltage of the light. The lamp is caused to provide a pseudo-random candle simulating effect.

Abstract: A parking lamp operating system reduces the electrical load on the battery of a vehicle, such as a truck, during periods when the vehicle engine is off but the parking lamps of the vehicle remain on wherein a switched signal input from the battery is modulated to provide a pulse-width-modulated output to the gate of a power transistor having a power input from the battery and an output to the parking lamps. The pulsed signal causes the transistor to intermittently switch the power to the lamps thereby reducing the effective voltage thereto while providing sufficient light output to be observed. The modulator may be bypassed by a second signal line connected to the vehicle alternator to provide a continuous signal to the transistor gate, thereby providing full power to the lamps when the engine is running.

Abstract: A self-oscillating half-bridge inverter is powered from a power-line-operated DC voltage source by way of an EMI filter. The inverter is loaded by way of a series-tuned high-Q LC circuit connected across its output. A pair of fluorescent lamps is series-connected across the tank capacitor of the LC circuit. The inverter has two bipolar transistors, each driven by an associated saturable current transformer that provides for a transistor ON-time dependent upon the magnitude of an associated bias voltage. One of the transistors has a control arrangement connected in circuit with its associated saturable transformer and operative to control the magnitude of its associated bias voltage. As the magnitude of this bias voltage is controlled, the magnitude of the voltage across the tank-capacitor, as well as of the current available therefrom, is correspondingly controlled.

Abstract: A two-terminal, alternating current power control device connected in an electrical path between a load and a remote switch, comprising a current switching device, a controlling device and a direct current power supply device. The current switching device provides a low impedance electrical path in response to the application of triggering signals thereto, and provides a high impedance electrical path in the absence of the triggering signals. A control circuit is provided for applying triggering signals to the current switching device as the proper time in the AC cycle, and is responsive to a momentary interruption in the applied AC voltage so as to effect change in the power intensity or timed duration of power delivered to the load. A remote switch in the electircal path can be the source of a momentary power interruption.

Abstract: A ballast circuit for a gaseous discharge lamp, particularly a neon light, includes a diode bridge rectifier for producing a d-c voltage from an a-c input and a transformer with a secondary winding connected to the lamp and a primary winding connected to the rectifier. A switching circuit is connected to the transformer primary winding for controlling a flow of current therethrough from the rectifier. The switching circuit includes at least one MOSFET having a drain terminal connected to the transformer primary winding and a grounded source terminal. A control circuit is connected to a gate terminal of the MOSFET for controlling the on and off times thereof, the control circuit including a pulse generator for producing a train of pulse-width-modulated rectangular pulses of substantially a single frequency fed to the MOSFET's gate terminal.

Abstract: The junction temperature rise of a power MOSFET serially connected to a lamp whose resistance nonlinearly increases during turn-on is moderated by the use of control circuitry which initially sets up a relatively low essentially constant current flow through the lamp and transistor and then automatically after the lamp resistance reaches a preselected level, the lamp is allowed to draw significantly more current. The size and therefore cost of the power MOSFET is reduced significantly because the magnitude of the current spike generated by turning on the lamp is significantly reduced the use of the novel control circuitry.

Abstract: An automatic battery powered video light (10) is supplied power by a d.c. battery (16). A light (20) is connected between a first terminal of the battery (16) and a MOSFET switch (46), which is connected to a second terminal of the battery (16). A control circuit (24) controls the opening and closing of the MOSFET (46) to supply power to the light (20) and disconnect power from the light (20). The control circuit (24) includes a light sensor (36) for sensing ambient light and reflected radiant light from a scene (14) and a pulse modulator (40) for controlling the MOSFET switch (46). The modulator (40) adjusts pulse frequency and therefore closing time of the switch (46) when the sensor (36) senses time low light levels, and vice versa. Also provided is a dual filament light (20') wherein each filament (52, 54) is independently controlled to enhance color balance.

Abstract: A circuit and a method for controlling the dimming of incandescent lights using a pair of antiparallel connected SCRs which are fired at the same frequency as the frequency of the AC line power to achieve phase control of the power supplied to the light. Only one SCR of the pair is utilized in the 0% to 50% brightness range while both SCRs are utilized in the 51% to 100% brightness range.

Abstract: An illuminated aerial marker for a high voltage transmission line using a spherical colored opaque capacitor with gas filled lamps electrically connected, exterior to the capacitor with one electrode of the lamps connected to the high voltage source and the other to the conductive area of the capacitor or capacitors. The lamps are spaced and sized to provide illumination with nighttime conspicuity of at least 4,000 feet when the lamps are activated.

Abstract: Electronic ballasts are essentially composed of a series connection of a harmonic filter that has its input side connected to the AC line, a rectifier and an inverter to which is connected at least one load circuit composed of a series circuit of an inductor and a parallel circuit composed of a fluorescent tube and a capacitor. When a high electric tolerance is required of such a ballast in view of a desired increase in the power factor, standard circuit designs required a relatively expensive storage capacitor that smooths the AC rectified line voltage. In order to be able to use a storage capacitor that has a lower electric tolerance in comparison to the required voltage tolerance of the ballast, a storage capacitor is incorporated into one of the two capacitor branches of the inverter which is composed of a switch bridge arrangement having two switch branches and two capacitor branches, this storage capacitor being connected in series with the actual load.

Abstract: A circuit arrangement for operating a high-pressure sodium lamp is provided with two lamp connection points. The circuit arrangement comprises a controlled main switching element, a control electrode of which is connected to a control circuit. The circuit arrangement is provided with a measuring impedance in series with a lamp connection point and with a measuring impedance parallel to the lamp connection points. The measuring impedances are connected to the control circuit. A combination of a resistor and a capacitor is further connected to the control circuit and this combination is connected in series with one lamp connection point.

Abstract: A fluorescent lamp is connected in parallel with a resonant L-C circuit powered by a series-applied high frequency voltage from a self-oscillating inverter power supply. The frequency of the series-applied voltage is about 33 kHz during the brief initial period before the lamp ignites, but falls to about 30 kHz after the lamp has ignited. As a result, the detuning taking place in the L-C resonant circuit due to changing parallel-loading is compensated-for by correspondingly changing the frequency of the series-applied voltage. This detuning effect is particularly pronounced in situations where there is a large magnitude-ratio between the lamp's ignition voltage and its operating voltage.

Abstract: An ignition circuit for fluorescent lamp includes a transformer having coreless windings connected in parallel with a fluorescent lamp with the coreless windings having inductive reactance matched with a capacitive reactance or internal resistance of the fluorescent lamp for forming a harmonic oscillation of a multivibrator in order for stably igniting the fluorescent lamp for saving electric energy.

Abstract: An electric arrangement for igniting and supplying a gas discharge lamp (1). The arrangement is connected to an alternating voltage source and comprises a rectifier bridge (7) connected to a DC/DC converter provided with a rectifier element (11), a coil (10) and a high-frequency switched semiconductor switching element (12) coupled to a drive circuit. The DC/DC converter is connected to the input terminals (16, 17) of a high-frequency DC/AC converter incorporating the lamp and provided with semiconductor switching elements (21,24). A capacitor (15) is arranged between the input terminals of the DC/AC converter and a sensor (22) for measuring the converter current is arranged between one of the input terminals (17) and a semiconductor switching element (21) of the DC/AC converter. The lamp is connected in series with a frequency-dependent impedance 20.

Abstract: Disclosed is a novel lamp-lighting device, comprising a full-wave rectifier composed partially or entirely of thyristor(s), said full-wave rectifier having both an input terminal connected with an ac source and an output terminal connected with a lamp; a smoothing means connected in parallel with the lamp; means to detect a voltage across the lamp that exceeds a prescribed level; and means to control the conduction angle of the thyristor(s) dependently on the magnitude of the voltage, said controlling means being operable in association with said detecting means.

Abstract: Disclosed is a novel lamp-lighting device, comprising a full-wave rectifier having both an input terminal connected with an ac source and an output terminal connected with a lamp, a smoothing means connected in parallel with the lamp, means to detect a voltage across the lamp that exceeds a prescribed level, means to switch the operation of said rectifier to half-wave rectification mode, and means to connect said switching means with said detecting means.

Abstract: A discharge lamp energizing arrangement comprises a starter and a generator adapted to maintain a discharge current in the lamp. The generator includes a first circuit arranged to couple in series a D.C. voltage source, a first switch and a second switch. When the first switch is closed the second is open and vice versa. A second circuit, arranged to couple an inductance and the lamp in series, is connected in parallel with the second switch. The switches are operated by a first control means which employs the signals received from an oscillator. The starter includes a third switch connected in parallel with the lamp terminals. The third switch is operated by a second control means itself operated by the first control means. When the energizing arrangement is turned on the third switch is closed and it subsequently reopens on the first occasion that the first switch passes from the closed to the open state.

Abstract: A high-pressure discharge lamp comprising a discharge vessel provided with an external auxiliary electrode connected to a starter circuit in the lamp. The starter circuit comprises a voltage division circuit between the connection terminals of the lamp and parallel to the discharge path. A switching element of the starter circuit shunts the voltage division circuit in part and is electrically connected to a control electrode of a semiconductor switch, connected in series with the discharge path and in parallel with the voltage division circuit. As a result a starter circuit and a lamp current limiting circuit are thus combined in the lamp.

Abstract: A wall box dimming system assembly controls the intensity level of a plurality of groups of lights in accordance with a plurality of preset scenes. The electronics for carrying out the dimmer operations are preferably mounted in a housing adapted to fit in a standard four gang wall box. A face plate assembly is coupled to the housing and has a larger profile than the housing as viewed from an entry position located in front of the face plate assembly. At least some of the control switches which enable the operator to switch control over the dimming levels from scene to scene and/or turn the system off are located outside of the profile of the wall box housing. The face plate assembly includes a support plate and a window pivotally connected to the support plate and moveable between a closed position, wherein access to slide potentiometers which control the dimming levels of the lights is blocked, and an open position, wherein the operator can gain access to the slide potentiometers.

Abstract: A ballasting circuit for fluorescent lamps includes a series-connected current limiting ballast element and an electronic assist circuit. The ballast element has a high voltage side connectable to a commercial 110 VAC/60 hertz power source and a low voltage side connected in series with the lamp. The electronic assist circuit has a full wave bridge rectifier input means connected to the low voltage side of the ballast element and a transformer output means connected in series between the ballast element and the lamp. The electronic assist circuit generates a relatively high frequency, high voltage excitation signal prior to lamp conduction to assist in starting the lamp. After lamp conduction begins, the low voltage side of the ballast element drops to the normal operating voltage of the lamp and the excitation signal amplitude correspondingly drops, but is not eliminated, so as to maintain lamp operation with low frequency power supplied from the commercial power source.

Abstract: A circuit arrangement for A.C. operation of gas discharge lamps comprises a full-wave rectifier (1) connected to an alternating voltage source. The direct voltage is supplied to a combinatorial circuit part (3 to 8) in the form of a direct voltage converter, to which is connected a bridge circuit (9) which comprises four thyristors. The transverse branch of the bridge circuit includes the lamp (5). The full-wave rectifier (1) is followed by a smoothing capacitor (2) and an electronic switching element (14) is connected parallel to the bridge circuit (9). The switching element is switched to the conducting state in the vicinity of the zero passages of the input alternating voltage. As a result shortcircuits in the bridge circuit are avoided.

Abstract: A matching circuit arrangement for operating a high-pressure discharge lamp. The circuit arrangement is provided with first and second input terminals for connection to a supply source, each of which is connected to a respective first and second output terminal. The output terminals are intended for connection of the high-pressure discharge lamp. A first controlled semiconductor switching element A having a thyristor characteristic is included in a connection between the second input terminal and the respective second output terminal. A control electrode of the switching element A is connected to a main electrode BE2 of a second controlled semiconductor switching element B having a thyristor characteristics. The main electrode AE2 of the first switching element is connected together with the main electrode BE1 of the second switching element to the second input terminal. The main electrode AE1 of the first switching element is connected to the second output terminal.

Abstract: An adaptation circuit (3) for operating a high-pressure discharge lamp (1) via a controlled semiconductor switch (4) in series with the lamp. The control circuit for the switch (4) to comprise a voltage division circuit (5,6). The voltage division circuit is connected in parallel with the switch when the lamp is connected to the circuit output terminals (E,F) and one branch of the voltage division circuit comprises a parallel-combination of a capacitor (57) and a resistor (56). Thus, the variation of the voltage across the lamp influences the control of the semiconductor switch so that it is possible to stabilize, for the major part, the power dissipated by the lamp against, variation in the supply voltage and against lamp voltage variations during the life of the lamp.

Abstract: A plurality of groups of linearly adjustable control potentiometers control respective lights of a given light scene in a given area. A particular group of potentiometers to control the scene is selected by a respective push-button switch on the control panel. Each of the potentiometer control sliders has an LED which is illuminated when its group of potentiometers is selected. Each of the control potentiometers controls a respective dimmer control circuit. Respective fader circuits are connected to each dimmer control circuit. All fader circuits are adjusted by a single potentiometer having a logarithmic response function. The single adjustment potentiometer is mounted on the control panel. All of the dimmer control circuits are remotely located from the control panel. The control panel is covered by a solid cover or a translucent cover through which only illuminated LEDs on the potentiometer sliders are visible.

Abstract: An improved high power (40,000 watt) high intensity arc discharge power supply which provides reliable, automatic ignition control and enables precise variation of lamp power in dual AC and DC modes of operation over an extended dynamic range from 400 watts to 40,000 watts. A capacitive boost circuit is provided to supply the high voltage necessary to ignite the lamp. Upon start-up, the voltage on a boost circuit capacitor is monitored by an ignition circuit which automatically enables the ignitor when the voltage is at the required level and switches the ignitor off when the lamp starts. After ignition the boost charging circuit is disabled and the power supply operates in a normal mode. The power supply operates on a three phase alternating voltage input through a three phase bridge, switches it through a drive transistor and then supplies it to an inductor. The signal is then supplied through an H-bridge commutator to the boost circuit, the ignitor and the arc lamp itself.

Abstract: An AC polarity-reversing bridge ballast for an arc discharge lamp using an incandescent filament for resistive ballasting and standby illumination powers the filament during hot restart without modifying the low duty cycle operation of the starting oscillator and without introducing additional power switches. The switching elements of the polarity-reversing bridge serve the dual functions of reversing the polarity of the voltage supplied to the arc lamp during normal running conditions and energizing the filament during a restart condition.

Abstract: A laser device in which an output of a switching circuit for DC/AC conversion is applied through a filter to discharge electrodes to generate an AC discharge therebetween to use it as a laser exciting source.

Abstract: A touch operated electronic switch for alternating current including a full wave rectifying bridge and two unidirectional current electronic switches one being mounted in parallel with said bridge input and the other being mounted in parallel with said bridge output, each unidirectional current electronic switch being such a silicon controlled rectifier which can be triggered by a touch plate. Said bridge input poles are the two external connections of said A.C. switch. Said unidirectional current electronic switch inserted between said bridge output poles is combined with a low inertia accumulator of electrical energy such as a capacitor mounted in parallel or an inductance mounted in series therewith. A device comprising a neon indicator and its dropping resistor is mounted in parallel with said bridge input so as to faintly light in transparency the touch operated electronic switch for A.C. when it is turned off.

Abstract: A variable high-frequency ballast circuit for igniting and operating energy saver discharge lamps includes a high frequency inverter that energizes the lamps with a given high frequency voltage at which reliable lamp ignition is assured. The lamp current is monitored so as to automatically increase the lamp operating frequency to an optimum value as soon as the lamps ignite.

Abstract: A flourescent lamp lighting circuit comprising a rectifying circuit and an oscillatory circuit. The rectifying circuit comprises a rectifier bridge, capacitors and coils to rectify the local alternating power supply to direct power supply and provide rectified electrical power to the oscillatory circuit. The oscillatory circuit comprises two transistors and an L-C circuit which, taken together, form an astable circuit which generates and maintains oscillations. The frequency of the oscillations is determined by the nature of L-C circuits. The ON's and OFF's of the transistors are controlled by induction coils within which currents are induced by the variation of magnetic flux in the inductor coil of the L-C circuit. The high frequency oscillations in the oscillatory circuit induce high frequency electrical signals on a secondary coil which then lights the fluorescent lamp.

Abstract: A high frequency ballast circuit powered by a dc input voltage source for starting and operating a gas discharge lamp load, comprising: a means for providing drive signals, each the drive signal having a first and second state, a series switch having a conduction channel having a first and second terminal, the series switch having a control terminal responsive to the drive signals, the conduction channel is on (conductive) in responsive to the interval characterized by the first state of the drive signal and off (non-conductive) in response to a drive signal having a second state, and an inductor. A clamp diode is included. The inductor is coupled to the clamp diode cathode and to the series switch. A ballast reactance is included with a a power oscillator circuit, the power oscillator circuit has a transformer having, a primary winding having a first, a second and a center-tap terminal, a drive winding having a first and a second and a center-tap terminal, and an output winding.

Abstract: A switching circuit for turning on and off an electronic instrument, an electric lamp, or other electrically powered electric or electronic circuits, by means of a single switch, and which is constructed so that when the switch is closed momentarily and opened, the switching circuit remains "on" until the switch is again momentarily operated. However, when the switch is closed for a longer time interval, the switching circuit remains "on" for so long as the switch is closed and turns "off" when the switch is opened.

Abstract: An electronic energization circuit is provided to illuminate a gas discharge lamp that includes a transformer with a substantially rectangular hysteresis loop. A secondary winding on the transformer is connected to energize the lamp and at least one primary winding is provided on the transformer. Input voltage terminals may be DC terminals to supply an input voltage to the circuit. At least one semiconductor, such as a transistor, is connected to the input terminals and to the at least one primary winding, and a control means is provided for the semiconductor for unequal on and off conduction periods of the semiconductor. These unequal periods provide the conditions which eliminate the striations (bubbles) or dark spots in the gas plasma of the lamp, usually associated with high frequency energization.

Abstract: A two-terminal line-powered control circuit is disclosed in which a triac is used to switch AC power to a load. When the triac is not conducting, a portion of the voltage appearing across it is rectified and filtered and used to supply power to a radio control circuit. When the triac is conducting, the voltage appearing across inverse-parallel connected diodes, which are in series with the triac, is stepped-up using a transformer, then rectified and filtered and used to supply power to the radio control circuit. The radio control circuit is in turn used to control the operation of the triac in response to a remotely transmitted radio signal.

Abstract: A switched AC ballast is operated synchronously with the AC line during normal running of a gas discharge lamp to limit EMI and is locked in a single phase during start-up (i.e. ignition, glow mode and warm-up) to protect the bridge switches from high voltage starting signals. Devices having a high impedance control input, such as FETs, are employed in the switching bridge thus allowing control of the upper devices in the bridge without a floating power supply. A control circuit insures proper operation of the bridge switches during all operating modes of the discharge lamp.

Abstract: A power control circuit which receives an AC line signal input and includes operational amplifiers which receive the AC line signal after it has been rectified. Each operational amplifier respectively operates as a zero crossing circuit which produces a square synchronous pulsed signal, a ramp generator which receives the square synchronous pulsed signal and produces a sawtooth wave signal, a comparator which receives the sawtooth wave signal and produces a synchronous pulsed width modulated output signal which can be varied. A power bridge circuit receives the AC line signal input and is triggered by the pulsed width modulated signal to rectify the AC line input to pass a pulsed width modulated signal to the load. The signal passed to the load is varied by the setting of the comparator.

Abstract: A switch circuit is disclosed which warms-up a load prior to complete turn on. The circuit includes a single pole double throw switch and an amplifier. The input to the amplifier connects to the off throw of the switch and the amplifier is rendered nonconducting when the switch is off. However, when the switch is between its off and on position, as it is being thrown on, the amplifier conducts a half wave rectified warm-up current to the load. Then, when the switch is on, the amplifier is bypassed by a short circuit connecting between the on throw terminal of the switch and the load, and the load is driven to 100% capacity via this short circuit.

Abstract: A single power transistor oscillator circuit includes a single transistor oscillator coupled by an inductive means including an inductive coil and transformer to a DC potential development means with a wave-shaping means coupled to a secondary winding of the transformer to provide a substantially symmetrical AC potential centered about a zero level DC voltage and applied to a load circuit.

Abstract: A touch-responsive socket for receiving an electric light bulb and controlling the power delivered to the bulb in response to the touching of an electrically-conductive member includes a housing with a touch-responsive electrical circuit disposed in it between a light socket shell and a mounting base. The mounting base is assembled from electrically dissimilar base portions. An electrically-nonconductive base portion provides support for power conductors and means for connecting the circuit to the conductors. An electrically-conductive base portion, which fits to the nonconductive base portion, provides electrical conductivity between a touch-control signal input to the touch-control circuit and an electrically-conductive member that is touched to control the illumination of an electric light bulb in the socket shell.

Abstract: The switches of an AC to AC converter are switched synchronously with the AC supply voltage. EMI conducted to the AC power line is greatly reduced since the rectifier diodes are off at the time of switching, thus avoiding undesirable effects on nearby electrical apparatus. The converter is useful in a ballast for a discharge lamp.