an alignment mechanism for establishing line - of - sight alignment between a transmitter and a receiver has , a laser pointer that emanates a laser beam along a line - of - sight to illuminate the receiver with a bright spot . an unmodulated reflector at the receiver reflects the emanated laser beam for return path transmission toward the laser pointer to confirm alignment of the line - of - sight with the receiver . the transmitter is aligned substantially along the line - of - sight and is fixed in position . a shutter in the form of a chopping wheel modulates the emanated laser beam . the receiver is linked to a communications apparatus having an external antenna .