An invisible fence is an electronically generated 3-dimensional boundary that may take any geometrical shape to enclose an area, as well as surround individual animals, but is unseen by the eye. Invisible fences control animals that are wearing radio frequency (RF) receiving devices capable of capturing electronic signals. The majority of signals used in invisible fences are between 3,000 hertz and 300 gigahertz. Invisible fences use sensory cues to invoke a change in an animal’s behavior or movement. Large animals can be controlled using audio cues, such as whistles, beeps, the human voice or any combination of them. Electric shock is also a cue used to control animal movement. Most commercial invisible fencing devices contain RF receivers that contain safety features aimed at preventing inhumane cuing, thus promoting an optimal animal experience. High frequency RF signals are emitted from a ground-based transmitter; however many invisible fencing systems will require many transmitters when the containment terrain is rugged and uneven.
Read more about Invisible Fence: History, GPS-Fencing, Disadvantages, Innovations in Cattle Herding
Famous quotes containing the words invisible and/or fence:
“Did men but consider that the sun, moon, and stars, and every other object of the senses, are only so many sensations in their minds, which have no other existence but barely being perceived, doubtless they would never fall down and worship their own ideas; but rather address their homage to that eternal invisible Mind which produces and sustains all things.”
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Throwing a leg up over our fence of mountains,
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