Section III. BASIC PRINCIPLES
ionizes, and the capacitor bank discharges through
The operation of the searchlight is dependent on
the xenon lamp, supplying a high current surge
the performance of two major functions. The
to complete lamp ignition (arcing). After xenon
first function is the ignition and continual illumi-
nation of the xenon lamp, while the second is the
by maintaining a nearly constant dc voltage across
control of the searchlight modes of operation.
the xenon lamp through a ballast resistor,
b. Searchlight Modes of Operation. (fig. 1-10).
Lamp. Ignition of the xenon lamp is accomplished
The searchlight has two basic modes of operation:
by the lamp igniter, booster, and capacitor bank.
visible or infrared (IR), either of which can be
At power turn-on, the booster begins to charge a
operated in a compact (focused) beam, spread
capacitor in the igniter located in the searchlight
(defocused) beam, or a variable beam of light.
and the capacitor bank located in the control box.
The power switch on the control box is used to
When the igniter capacitor charge reaches 3,000
select visible or IR mode, and the beam switch
volts, the igniter applies 40,000 volts across the
controls the beam width.