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Smart Home Hacks
By Gordon Meyer
October 2004
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Bark like a Dog
You can protect your home with a real dog, or you can use the Robo-Dog to simulate one. And like any good dog, this module performs more than one trick.
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The X10 Robo-Dog module (http://www.x10.com/security/x10_dk9000.htm; $60) is truly a strange beast. Its purpose in life is to convince visitors that a vicious, barking dog is waiting to confront anyone who enters the home. It does this by playing a recording through the built-in amplifier and 4-inch speaker, which dominates the unit, as you can see in .

The dog, affectionately named ReX-10, sounds like a big dog with a serious attitude problem, provided that you're not standing too close to the unit. If you are, it sounds like a recording and might even induce a giggle. For this reason, carefully consider where you place the unit. You'll want it far enough away to mask its artificial qualities, yet loud enough to still be heard. Plan to spend a few minutes experimenting with different locations and volume settings when you set it up.

Figure 1. The X10 Robo-Dog

To use the Robo-Dog, you need only set its house code . The module automatically assumes the unit code of 1. In other words, if the module's house dial is set to N, its X10 address is N1. When the module receives N1 On, it will start barking madly. It will stop barking after about 30 seconds, or it can be silenced immediately by N1 Off.

The Robo-Dog is designed to work in partnership with other modules to provide a complete security setup. When you buy it, it comes with a wireless remote control that can start and stop the barking on demand. It works with security remote controls, too, so if you have an X10 alarm console, you can use the remote controls you already have. To do that, however, you'll need to follow the steps in the Robo-Dog manual to train it to respond to your system.

Additionally, the Robo-Dog can be triggered by a DM10A outdoor wireless motion detector (http://www.x10.com/security/x10_dm10a.htm; $30). The DM10A is a hybrid motion detector: it communicates with both home automation and security equipment by sending two different signals when it's triggered.

Instead of having the Robo-Dog controlled directly by a motion detector, one of the best ways to use a Robo-Dog is to make it part of what happens when a visitor approaches your unoccupied home. Anyone with bad intentions probably will be persuaded to look elsewhere when they hear what sounds like a fierce dog inside, see a few lights come on, and hear a distant radio playing .


The Robo-Dog can run off batteries—a whopping nine C cells—but this is intended primarily for backup power so that it still can bark when the power goes out. However, don't be tempted to run it solely off batteries. If it's not plugged into the wall, it can respond only to wireless signals, which means you'll be unable to control it from your home automation computer.

There's something else that's unique about the Robo-Dog, and I bet most people who have one don't even realize it. The module isn't commonly used, and its documentation is incomplete, so I had one for a few years before a message from Michael Ferguson, on the XTension discussion list (http://lists.shed.com/mailman/listinfo/xtensionlist), tipped me off that the Robo-Dog is also a wireless transceiver. That is, any wireless commands it receives for its house code are echoed to the power line. This means that all nearby motion detectors and Palm Pads can use it as their bridge to the power line, and thus to your home automation system, without you having to install a transceiver just for them. That's a nice bonus that not only saves a little money by pressing the module into double duty, but also enables you to eliminate yet another unsightly device from your home .

It's a very good dog, indeed.

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