This is my first post but I've been interested in the Arduino as someone who likes the idea of innovating and often thinks about it. I've only gotten through about half of the Arduino book that I have and only know the bare basics of electronics, but I do have experience coding. Anyways, I've unfortunately stumbled upon a real technological blunder of the invisible fence brand products when my cat came home without his collar and apparently there is nothing I can do about it. Invisible Fence offered to come out with a portable transmitter and try to find it for $100 but its only got a 12 foot range and there is no guarantee that they will find it (it's possible that the cat lost it outside of the yard). A brand new microlite computer collar costs $350. I'm really kicking myself for not getting a tile tracker and attaching it to the collar, but I'm wondering if it's possible to fashion something up with an Arduino? From what I know the collar is a receiver and can only buzz and produce a shock. Based on this article, invisible fence transmitters use a radio carrier frequency of either 7.5khz or 10.8khz with a 30hz modulation frequency. I think this will help a lot of people if I can only get some help figuring it out!
Arduino on its own cant receive RF signals. But it looks from the article that the collar is a receiver so I'm not sure how the locator is going to work anyway.. maybe they have a very sensitive receiver tuned to the local oscillator frequency of the collar? It would be hard to know without access to a working collar.
You could probably make the existing invisible fence transmitter portable, and go hunting yourself, but that would require figuring out how it is powered and substituting the appropriate batteries.
Also, there are restrictions on the allowable antenna configurations. You may have to add a resistor to the antenna loop to keep from burning the transmitter output transistor.
rw950431:
Arduino on its own cant receive RF signals. But it looks from the article that the collar is a receiver so I'm not sure how the locator is going to work anyway.. maybe they have a very sensitive receiver tuned to the local oscillator frequency of the collar? It would be hard to know without access to a working collar.
Before giving the dog/cat a shock, the collar emits an audible tone as a warning.
jremington's method should work if you get close enough to the lost collar to hear the tone, provided it's practical to disconnect the original transmitter from the system and 'go portable'. (The system apparently uses buried cables to set the boundaries which trigger the collar.)
@indigetal, to design and build your own transmitter, besides the obvious difficulties in reproducing the original signal, you'd need a second collar for testing. Do you have one?
The problem with those collars is they only work while they are within range of the buried antenna (which is something like 10 feet or less if I remember correctly). This works great when the animal is wandering around the yard and learns where the "fence", but if it is chasing something (dog, cat, rabbit etc.) and is up to speed, it goes through that zone very quickly and is now OUTSIDE the fence and free to wander off. As for finding it, you could build a transmitter that has the same characteristics of the "fence", and while increasing the power of the transmitter should give you somewhat better range, it may also trigger the collars on other nearby animals if they have the same collar (that should confuse everybody!!)
If you can design and develop a detector circuit (either using an Arduino, or not), then you are going to have to get a new collar to test it with, to make sure you are not wasting your time out hunting with useless equipment.
But if you obtain a new collar then you don't need the detector in the first place.
Thanks for all the replies, my cat is trained on the invisible fence, although he does get out on occasion. Its been working for the most part for over a year now. This is the first time that he's come home without the collar though. I have two cats, so there is an extra collar to work with and you know that I've already bought a tile tracker for that one as soon as I realized how inconvenient it is to lose a collar. The transmitter isn't under the house, I set it up in the kitchen. It's interesting that jremington mentions that I could make the transmitter portable, invisible fence does sell a portable transmitter with a 12 foot range, but I'm hesitant because it costs $180 and is still a pretty short range in my opinion. I'm getting that there seems to be a bit of a consensus that reproducing the signal using an arduino or some other device would be difficult though, so maybe buying the portable transmitter is my best option...
Hey guys been trying to gather as much info as possible on using the Arduino to make an invisible fence. I am struggling with the capabilities of the Arduino Uno. High current can't be used. Currently setting up 2 Arduinos and running one for the transmitter and one for the receiver. Using simple 18 gauge wire to create the perimeter. So I'm trying to figure out the magnetic field aspect of the project. If the wire is buried under ground will the Arduino be powerful enough?
