Vehicle horn Several languages have either borrowed or transcribed the name into their lexicons. In Japanese, the word refers to car horns in general, and in verb form () refers to sounding the horn. This is also true in languages such as French (), Italian (), Dutch (), Russian (), Polish (), Spanish (), Romanian (), Czech (), Turkish (), Indonesian (), and Korean (). In countries applying the Vienna Convention on Road Traffic, usage of audible warnings is limited, and allowed only in two cases: Vehicle horn A horn is a sound-making device that can be equipped to motor vehicles, buses,
Infrasonic burglar alarm Infrasonic burglar alarm The infrasonic burglar alarm reacts to shock waves in the air that are produced by a break-in. When an intruder tries to break a window or force open a door or a window, the resultant air pressure variations (or shock waves) produce sound vibrations in the air, from 0.1 – 50 Hz. These low frequency sound vibrations are captured by a very sensitive receiver in the alarm and converted into electronic signals. These signals are then passed through a pre-programmed electronic filtering system for analysis and when found positive, activate the alarm siren immediately; thus dissuading the