Pet fence

History:
– Pet fence created in 1973 by Richard Peck
– John Purtell bought rights in 1976 and rebranded it as Invisible Fence
– Invisible Fence Co became Invisible Fence Inc in 1990

Technology:
– Invisible fence transmits radio signal shaping enclosed area
– Pet wears collar emitting warning sound near boundary
– Crossing boundary triggers mild electric shock or combination of signals
– Only animals with equipment are affected by system boundaries
– Used for pet and livestock containment

Variants:
– Underground fence prevents pets from leaving yard with buried wire
– Wireless fences emit radio signal from central unit
– GPS collar determines proximity to virtual fence without physical installation
– Collars have multiple settings for tone or static shock levels
– Allows flexibility in boundary changes and containment of different-sized animals

Downsides:
– Underground fences do not exclude other animals
– Pets can still be prey to larger animals or people
– No warning mechanism for humans entering perimeter
– Requires maintenance of collar batteries
– Some animals become afraid to enter yard due to fear of shock

Upsides:
– Underground fences suitable for terrains where traditional fencing is not possible
– Modern systems suitable for cats to prevent road accidents
– Used to secure driveways and open areas
– New training protocols make it viable for cat containment
– University study found no long-term welfare issues with electronic containment of cats