The antenna portion of the unit has four directional receivers that correspond to the four relative bearing display light bars on the control unit. A ship operating radar in a frequency from 3 to 10 centimeters emits a stream of microwave pulses. When these pulses strike one or more of the detectors in the C.A.R.D. antenna, they are processed to light up the corresponding display. The intensity of the signal will determine the number of lights that will be illuminated. Current and voltage requirements, .045 amps at 12 volts.
transmissions travel line-of sight, so the distance at which a target is
detected is dependent primarily on two factors:
activate the system and set the level of sensitivity, simply turn the dial