Abstract: An apparatus and method for controllably generating smoke from a simulating smoke-generating fluid. A container holds a supply of simulating smoke-generating fluid. A generally vertically-disposed, hollow, elongated, tubular member having inside walls surmounts the container with a lowermost opening thereof in fluid communication with the container and an uppermost opening thereof capable of being placed in fluid communication with an area into which the smoke is to be introduced. Preferably, gas is moved into the tubular member at a portion thereof near the lowermost end and in a direction generally tangential to a radius of the inside walls such that the gas flows upwardly in a generally spiral-like manner.

Abstract: A high speed a.c. voltage regulator comprises a transformer having a plurality of switchable primary windings across which an unregulated voltage is impressed and which control the regulated voltage, and a secondary winding across which the regulated voltage is generated. During a regulation period, which comprises one cycle of the unregulated voltage frequency, peak unregulated input voltage is compared against an upward ramping reference voltage to control a source of clock pulses, where the instantaneous level of the reference voltage is related to the number of clock pulses generated during a regulation period. The number of clock pulses generated during a regulation period controls the switchable windings.