How does Radio Fence / Invisible Underground Fence Really Work?

A very popular pet “fence” more commonly used for dogs is the radio/shock collar system often called radio fence, electric fence and invisible underground fence. The system uses a wire, typically buried a few inches underground, to broadcast a strong FM radio signal with a range of a few feet in all directions from the wire. The signal weakens further from the wire but is still detectible several feet from the wire. The FM transmitting wire is run in a loop that follows the perimeter in which an animal is to be contained. When the shock collar is within several feet of the wire in the ‘weak signal” area, an alarm will beep intending to alert the animal that proceeding will mean a shock. The signal to shock is triggered once the collar enters the “strong” FM signal within a few feet of the wire.

In principle, an animal is to be trained to understand that the beep noise is a warning and they are not to proceed forward. In practice the problem becomes that an excited animal ignores the beep and runs through the ‘strong signal” shock area. Once out of the “strong field” area the shock stops. Now the animal is outside the invisible underground fence. In fact, it will encounter the same warning beep as it would inside the radio fence / invisible underground fence as it approaches the “weak” radio fence signal from the outside. Essentially the animal’s training will tell them NOT to go back into the radio fence because it will get shocked.

Many pet owners have had very good success with this system. That said, it is not a physical barrier. It does not keep other animals out and it will not keep an overly exited pet in. Purr…fect Fence offers physical barrier fences and fence add-on systems for cats and fence add-on systems for jumping and climbing dogs. If you are looking to secure and existing fence for cats please click here If you want cat containment but do not have a fence click here If you have a dog that is climbing over or jumping your existing fence please click here.

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Keith & Elaine Rahn
Sullivan, Wisconsin

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