The alarm has been around for at least that long. Its history is both bright and tarnished. It was quite simply based on people power. A watchman was selected to remain alert during the hours of darkness. His duties were exactly as alarm systems are today. Notify the peaceful inhabitants of a fire, burglary or invasion and protect them. He was the basic town alarm system, the prototype of today's house, personal or car alarms. The quality of the alarm was equal to the skills, talents and commitment of the people hired to be the alarms of the town. We still have the "people powered" alarm, they are called policemen and firemen plus we have the silent guardians provided by electronics.
Modern car alarm systems are one of the hallmarks of 21 st century security engineering. If the banks of the past three hundred years had used this technology then we would have most of the original money invested in them. Home alarm systems are also marvels of the modern age. Both automobiles and homes are protected by multiple sensor systems. These are electrical circuit systems, infrared optics, ultrafrequency sound, visual surveillance, closed circuit television and broadband telecommunications. There are even low powered radar systems, usually powered by continuous wave radar, which can pin point individuals location in complete darkness. Other retail alarm systems, which are also available, use pressure variation, both high and low frequency sonar and laser detection systems. Depending on the level of privacy desired, a person can lock down both a car and a home to a point where it is extremely difficult for theft or illegal entry to occur.
It is true that technology has tightened the gaps of yesterday. However, it still requires human intervention and service. Unlike Isaac Asimov's, "I, Robot", our present culture relies upon private security agencies to operate all the wonderful gadgetry. It still needs them to interpret what the host of radars, sonars, integrated circuits and various communiqués mean. This brings us full circle back to the original alarm system, the village watchman. Security and an adequate alarm system is an issue of individual trust. Such a value can only be taught through the traditional institutions of a society. You have to teach men and women at an early age that it is permissible to have private property. You also have to teach them that individuals have the right to freedom and to be happy. Next, you have to teach them that it will sometimes cost them dearly, maybe even their lives. If you want, safety and good alarms build more churches and civic-minded schools.
Available retail alarm systems, use pressure variation, both high and low frequency sonar and laser detection systems