Abstract: An electronic circuit is shown to initiate and sustain conduction in a gaseous discharge light. A breakover device and snubber network, isolation network, and self-adjusting symmetrical high voltage pulse generator are incorporated into a standard gaseous discharge light assembly typically composed of a power source, gaseous discharge lamp ballast apparatus, and gaseous discharge lamp. The electronic circuit is used (1) for initiating and sustaining conduction of electrical current through gaseous discharge lamps, (2) to provide active suppression of transient voltages both within and external to the gaseous discharge lighting apparatus, and (3) to provide significant attenuation of the propagation of undesirable conducted and radiated radio frequency interference from the gaseous discharge lamp and the overall associated ballast apparatus.

Abstract: A photosensor for detecting the light intensity of an external light source, usually the sun, which is illuminating an area is used as the sensor for a control network of an artificial lighting system for that same area to compensate for light intensity variations. The voltage output from the photosensor is applied to a logarithmic-to-linear device which is used as an input to a comparator for producing an inverse output that drives the artificial lighting system. The logarithmic-to-linear device inserts an element into the overall control system that provides compensation that corresponds to the perceived linear light change of intensity that actually occurs when there is an actual logarithmic light change.

Abstract: A thickfilm manufactured resistive element that functions as a normal resistor in an HID lamp starting circuit where high voltage starting pulses are produced, but which exhibits a negative and extremely non-linear voltage coefficient of resistance characteristic when potentially destructive high voltage spikes occur as a result of circuit interruption during operation of the lamp. The resistive element is comprised of a mixture of refractory conductive, semiconductive, and nonconductive materials of an amorphous noncrystalline nature having the physical structure of a supercooled liquid, commonly referred to as glass, which has been discovered to exhibit the property of having an extremely non-linear voltage coefficient of resistance.

Abstract: A spark arrestor for protecting a high intensity, gaseous discharge lamp, ballast and other circuit components against being damaged or destroyed by a large build up of voltage. The arrestor includes a multi-sided low dielectric disc with star-like conductive material on each side, the points of the star being opposite the mid-points of the sides. Terminals for connecting the spark arrestor across the secondary of the ballast, or other similar location, are connected to each of the star-like conductive materials. There is a non-conductive tubular shield around the disc to protect againt spreading of the spark, but the terminals extend from the ends of the shield for connection purposes.