Alarms can help deter crime.
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Burglar alarms have become standard equipment in stores and other businesses, and they're becoming increasingly common in private homes as well. If you've ever shopped for a home security system, then you know there are a wide variety of options available. These systems range from do-it-yourself kits you can pick up for $10 to sophisticated whole-house security networks that must be installed by professionals. But, as it turns out, most alarm systems are actually built around the same basic design concepts.
In this article, we'll take a look at these concepts and examine a few specific alarm designs. As you'll see, some of the most effective alarm systems are also the simplest.­

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