Abstract: A high frequency gas discharge lamp dimming ballast with good line power factor is disclosed. The unit is controlled by a current sensing loop which senses control switch current rather than lamp current and employs simple circuitry with sufficiently rapid control response necessary to maintain high line power factor and stable lamp operating characteristics over a very wide range of light output. An isolated output transformer provides protection against most common miswire conditions and accurately regulates lamp energy over a wide range of input and lamp arc voltage conditions. A pulse width modulated control input provides an isolated control input for easier wiring and reduces the susceptibility of the control to noise interference.

Abstract: A circuit arrangement for starting and operating a high-pressure gas discharge lamp having an outer starting electrode connected to an igniter. A full-wave rectifier (1) is connected to an alternating voltage supply (A, B) and has an output shunted by a series arrangement of a diode (4) and a capacitor (5). The capacitor is discharged in part through the lamp (3) after each half period of the alternating voltage. A resistor (6), which is high-ohmic with respect to a current limiter (2), is connected in the current circuit between the end of the capacitor (5) facing the diode (4) and the lamp (3). Thus, starting of the lamp is facilitated.

Abstract: A discharging element energizing circuit for a discharge-type fire alarm sensor unit including a discharging element, wherein a power supply circuit gives a power voltage to the discharging element in the form of periodical output pulses making same ready to discharge and a feedback circuit is provided to supply a feedback signal obtained from the discharging element to the power supply circuit so as to vary the interval of the output pulses. The sensor unit is continuously sensitive to ultraviolet rays only caused by a fire disaster, thus preventing a malfunctional alarm. Power consumption is reduced considerably, allowing the unit to be operated with commercially available dry cells.

Abstract: The specification discloses a starting transformer having a floating secondary. Coupling between the line and high voltage electrodes is effectuated through the distributed capacitance between the primary and secondary windings.

Abstract: It is the purpose of the present discharge lamp lighting system to provide reignition energy to a discharge lamp in each half cycle of the a.c. power source. The discharge lamp is connected to a conventional a.c. power source through ballast means and an oscillation booster circuit, which provides an intermittent oscillation output for the reignition operation of the discharge lamp. The operation period of the intermittent oscillation output is so controlled that the reignition operation period is included in each half cycle of the discharge lamp current. The lamp voltage and source voltage are established to agree as much as possible with each other for minimizing the terminal voltage of the ballast means, whereby a compact and economical device with a small inductance ballast means is achieved.

Abstract: The invention concerns an electrode arrangement for improving the ignition readiness of gas discharge lamps, particularly for flash tubes. The ignition electrodes consist of a plurality of wire loops which surround the surface of a gas discharge tube. The mutual space between neighboring wire loops is smaller in the center portion of the tube than towards both end portions.