Audible, deterrent type burglar alarm - includes cassette player reproducing aggressive animal noises, e.g. guard dog, upon intruder detection

摘要

The alarm includes a number of detectors (1) sensitive to a potential intrusion connected to a central unit (5). This in turn is connected to a playing-only cassette player (7) deriving power either from batteries (6) or the mains The cassette player may be turned on either manually (3), or automatically (4). When an intrusion is detected, the cassette player is operated, reproducing the noise of an aggressive animal. The detectors may include magnetic or seismic sensors at the perimeter of a property, and radar, ultrasound and infrared sensors responsive to the presence of an intruder within a monitored space. Infrared long distance barriers may also protect the outside of a property.