How to Adjust the Field Width on an Invisible Fence

Invisible underground fences help keep your pets in the yard without having to install unsightly and expensive aboveground fences. Your pet's collar acts as a radio receiver, and the buried fence acts as a transmitter. If your pet gets too close to the line, the collar receives a signal from the transmitter and delivers a mild corrective shock. With a simple turn of a knob, you can adjust the strength of the radio signal, altering the width of the correction zone.

An invisible fence helps keep pets safely in your yard.
  1. Attach the included test light to the receiver collar according to the manufacturer's instructions. Hold the collar by the strap with the test light attached.

  2. Turn the boundary control knob on the invisible fence control box to the middle setting.

  3. Walk toward the buried line, holding the receiver collar at the height of your pet's neck. Move closer to the line, listening for the audible warning and watching for the test light to flash. Note the distance from the line when the audible tone occurs and when the test light flashes.

  4. Turn the boundary control knob clockwise to increase the width of the boundary or counterclockwise to decrease the width. Test the width of the boundary with the receiver collar after each adjustment.

  5. Remove the test light from the collar when the desired boundary width is achieved.


  • Test the collar and fence for proper operation frequently to help prevent failures that could allow your pet to leave the yard.

About the Author

David Young has written for the website for the Save Darfur Coalition and is currently writing articles for various other websites. Young holds a Bachelor of Arts in philosophy from Western Carolina University.