The Theory of Nothing

How does an invisible fence work?

How does an invisible fence work?

You don't hear about this very often these days. There used to be lots of ads for a magic system that could keep your dog inside your property boundary without having to install a real fence. They called it an invisible fence. All you had to do was have a wire installed underground and put a special collar on your dog and you were good to go.

The proper term for this product is an Electronic Pet Containment system, and it was advertised as being much less expensive than a physical containment fence. It worked by sensing when your dog was about to cross the boundary--the underground wire--and then cause the collar to emit a high frequency sound that only the dog could hear. The alarm sound becames stronger as the dog approaches the invisible fence. Other animals and humans can't hear the warning sound. If the dog crosses the boundary, it receives a mild electrical shock. Eventually, the dog learns not to cross the boundary.

There are two ways to implement this concept. One is with a buried wire that emits a radio signal that the dog's collar picks up. Another way to do this is to have a central radio signal generator that's programmed to detect when the dog goes beyond a certain radius.

The other main method is to use GPS to determine where the dog is relative to the owner's property boundary. This avoids installation of a wire or a central signal generator, but it suffers from the usual GPS errors.

There are some basic problems with this concept of restraining a dog without building an actual fence. One is that other animals can attack your dog. They don't have a collar to restrain them from crossing your 'invisible' barrier. The same goes for humans. Someone could kidnap your dog despite the presence of the invisible system.

Some of the other problems involve failure of the equipment, specifically the collars. If they stop working, the dog will be gone. One way that a collar can fail is if the battery runs down. The batteries in these things can be expensive.

Another issue is with the sturdiness of the wire that picks up the dog collar signal. The wire can break.

There are products out there that can help you do it yourself. That will save a lot of money that the services charge for installation.

Some people don't like this idea because of the fact that the collar shocks the dog. If you read the reviews on the Internet, you find quite a bit of complaints about the systems. That doesn't surprise me. Most products, especially technical ones, have dissatisfied customers.

Thanks for reading.