Abstract: A method and apparatus for ionizing a rare gas in a gas type cold cathode lighting source using a high voltage direct current pulse. Direct current pulses are applied to the lighting source, the current flow to the lighting source is sensed, upon ionization of the gas the voltage level of the pulse is reduced and the pulse width is increased so as to provide a proportionally increased constant current high voltage direct current pulsed output, and the polarity of the pulses to the light source is periodically reversed.

Abstract: An apparatus and method are provided for illuminating a light source in real time response to an event of changing magnitude. A pulsed electrical signal is generated which has a pulse repetition frequency corresponding to the magnitude of the event. The pulsed electrical signal is then utilized to control the power provided to the light source such that the intensity of light energy provided by the light source varies in real time with changes in the magnitude of the event.

Abstract: A field effect transistor of the N junction, P junction, or MOS FET type and having a load connected in series with its source and drain electrodes is normally biased off by a diode circuit which causes the FET to conduct when an input voltage is applied to an input terminal of the diode means.