We’ve got a four and a half year old yellow lab. He’s a typical, goofy, happy lab and we’ve had him since a pup. He knows the usual stay, sit, lie-down commands but has a rather short memory, particularly when there’s the smell of food in the air. He’s not quite as bad as Marley in the book and movie “Marley and me” but close.
Anyway, not unlike in the movie, when he got into the garbage in the kitchen for the hundredth time, climbed on the counter to get the food, ate several bottles of pills that accidently got left on “only” a chest high shelf, (well, you get the picture) the dear wife was near to a, “It’s me or the dog” moment. Anyway she called up the local “Invisible Fence” people and they installed an indoor invisible fence that, aside from the price, has done wonders for peace and harmony at our house.
The unit is installed in the basement with wires running under the subfloor to act as the antenna which keeps him out of those areas on the first floor when he has the receiver/shock collar on. The cheesy looking unit is about 3″ X 3″, looks like it cost about 99 cents, and the antenna wire is very light gauge paired wire. As near as I can figure out, the signal cancels itself out when running through the paired conductors, but is active when the pair is pulled apart and say, goes around the perimeter of a room.
I’d like to move it to a new house.
1) Do I pretty much have it figured out how the paired cancels the signal vs. split pair carries the signal?
2) Is it important for the gauge of the antenna wire to be that flimsy?
3) If the answer to # 2 is no, then what would be a good wire to use and where to get it?
Thanks for your answers.
Edited 4/12/2009 4:25 pm ET by fingers
Replies
We did it on the cheap, bought a kit and added a bunch of wire - stranded 18 gauge with a black, UV-resistant jacket - bought a 1000' spool.
Ours is a big "C", because our neighbor has a fence that the dogs talk through, so it's double-wired; about 3' apart minimum. I think the total length is about 1300'.
Surface mounted to the ground - just used the 16" OC "dragon's teeth" wire for holding insulation up, and bent them into big staples - they've been fine, and we mow over the wire all the time.
Coming into the house, it's laid close together ~1-2", so the dog can walk over it.
Forrest
The signal is cancelled when you twist the pairs. You can get the wire at HD or Lowes, IIRC, and it's not very expensive. Easier to buy new than to strip out the old, IMHO.
Mike Hennessy
Pittsburgh, PA
most pet supply stores have the wire. It is as easy as you think.
Sounds about right. The distance the signal travels upward is going to be roughly equal to the distance between the wires. Thus the wires probably need to be 2-3 feet apart to produce enough of a "fence" for a large dog, and can be farther apart (within reason) to protect an area. There should be no real restrictions on the type or thickness of the wire.
"The distance the signal travels upward is going to be roughly equal to the distance between the wires."
I'm not sure I follow that. The signal is only generated by places where there is only a single wire. And it is transmitted out equally along the wire, the effective distance limited by the power setting of the transmitter. In a normal installation, the wire forms a single-strand loop around the protected perimeter. You twist the wires together to form a "no signal" area, like for when you want to take the wires back into the house to attach to the signal generator. No matter the size of the beastie, it's one wire making a loop around the perimeter.
See here: http://www.discount-pet-superstore.com/outdoor/layouts.htm
Mike HennessyPittsburgh, PA
The wires are creating the primary of a transformer. The farther apart the wires are the farther out the lines of flux will reach. But of course the lines of flux are subject to Gauss's law and get weaker the farther you get from the wire. Once the wires are maybe 20 feet apart the flux in the middle is too weak to be detected by the collar.
The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith
Yeah! That seems to be the way it works, except that in my basement the paired wire isn't twisted. Maybe that's the ideal way to do it, but with such light gauge they used in my installation, for all practical purposes, it doesn't make a difference.
That doesn't seem to jive with the way they laid out the wires in my basement. It seems that where the wires are single (in other words not paired) the signal is given out, and the signal strength from that single wire doesn't seem to vary if the matching single wire is ten feet away or forty feet away. Oh, and that signal seems to work on the receiver collar about three feet in any direction from the wire.
Edited 4/13/2009 9:28 pm ET by fingers
Once the wires get a certain distance apart like I said the signal in the middle will be sufficiently weak to not be detected. How far apart that is (ie, what diameter circle the dog can be in the middle of without getting jolted) depends on the strength of the signal and the sensitivity of the collar.Picture flux lines circling the wires. When the wires are close together the flux lines are so close to each other that they cancel out, and so the signal doesn't travel very far.
The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith