High Quality Content by WIKIPEDIA articles! A Voice Activated Radio Dispatched Alarm, or VARDA-alarm, is a type of burglar alarm that, when activated or 'tripped', broadcasts the type and location of alarm over the local police radio frequency using a pre-recorded audio message.Burglar (or intrusion), fire, and safety alarms are electronic alarms designed to alert the user to a specific danger. Sensors are connected to a control unit via low-voltage wiring or a narrowband RF signal which is used to interact with a response device. The most common security sensors are used to indicate the opening of a door or window or detect motion via passive infrared (PIR). New construction systems are predominately hardwired for economy.

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