it's important to remember that the infrared link between remote and receiver has its limitations. The black, semitransparent part of both remote and receiver house infrared sensors that need to be exposed and within a line of sight of each other to maintain a link. The remote is actually sending out invisible light signals, and they won't reach the receiver if something blocks their way or if they are sent in the wrong direction. They can, however, bounce off walls and ceilings; so as long as you remain indoors, pointing the remote in the receiver's general direction is sufficient. you can also cover up the receiver almost entirely in constructions intended for indoor use, as figure 13-4 shows.A 2*2 opening around or slightly above the receiver's top will do the job outdoors' maintaining thr link between remote and receiver is more difficult: The remote has to be aimed with good precision, and its range can drop to as little as 1 m if the receiver's sensor is exposed to strong sunlight