Automobile Alarms
A motor vehicle's horn, bell, siren
or other sounding device that is easily audible at 300 feet.
Some alarms have an automatic shut-off and reset
capability that provides for the alarm to sound for not more
than four minutes, shut off and then immediately rearm
itself. Other alarms have a backup battery which is an
auxiliary power source that trips an alarm device if the
main power source is disconnected or if the wires to the
alarm device are cut or disconnected.
Alarm Systems
The purpose of an alarm system is to make enough noise
that a thief will leave without the vehicle. These alarm
systems take many forms:
- Door sensor - a mechanical switch that activates the
alarm device if the door is opened without deactivating
the alarm system.
- Glass sensor - an electronic device that activates the
alarm if it detects the sound of breaking glass or metal
in contact with glass.
- Motion sensor - a mechanical switch that activates the
alarm device if the vehicle is jacked up or towed.
- Trunk sensor - a mechanical switch that activates the
alarm device if the trunk is opened while the alarm
system is armed.
- Ultrasonic sensor - an electronic device that
activates the alarm device if an ultrasonic field is
disturbed inside the motor vehicle.
- Vibration sensor - a mechanical or electrical device
that activates the alarm device if any part of the motor
vehicle is bumped, causing vibration.
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