A xenon arc searchlight incorporates a high frequency/high efficiency electronic
circuit that allows lamp ballasting and charging of the system battery to occur
over a wide range of external DC power supplies. The xenon arc searchlight has
a converter circuit coupled to both the battery, the ballasting circuit and the
arc lamp for converting DC voltage from the battery to pulse width modulated switched
current to the arc lamp in which the DC voltage is switched by parallel switching
transistors. The ballisting circuit is controllable by a switch to vary current
supplied to the converter circuit and hence intensity of the lamp which discrete
steps in intensity of the lamp are not visually perceptibly different between one
step to a next step in the sequence of steps of the current to the lamp. The lamp,
ballast, battery and charger are provided in a single rugged package.
