Self-arming alarm

Posted on Oct 10, 2012

The circuit has a built-in, self-arming feature. The driver turns off the ignition, presses the arm button on theComputalarm, and leaves the car. Within 20 seconds, the alarm arms itself—all automatically! The circuit will then detect the opening of any monitored door, the trunk lid, or the hood on the car. Once activated, the circuit remains dormant for 10 seconds. When the 10-second time delay has run out, the circuit will close the car`s horn relay and sound the horn in periodic blasts (approximately 1 to 2 seconds apart) for a period of one minute. Then the Computalarm automatically shuts itself off (to -save your battery) and rearms

Self-arming alarm
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If a door, the trunk lid, or the hood remains ajar, the alarm circuit retriggers and another period of horn blasts occurs. The Computalarm has a "key" switch by which the driver can disarm the alarm circuit within a 10-second period after he enters the door. The key switch consists of a closed circuit jack, Jl, and a mating miniature plug.

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