Electronic Dog Collars and Underground Electric Fences

Peg me as a "bleeding heart", but I think attempting to modify the behavior of your pet by delivering shocks is a very lazy and somewhat sad way of going about it. Pets are not remote-controlled devices.

But more importantly, this really isn't the kind of project you want to tackle yourself - especially if you're an amateur. There are government rules about constructing devices which emit RF. You have to be careful that they don't interfere with other devices, etc.

But more importantly, the last thing your - or any - pet needs is some hacked-together bit of junk controlling juice to its collar. Do something bone-headed with your circuit design and maybe one day the poor thing gets subjected to "correction" all day while you're at work.

As much as it pains me to recommend it, if you insist on employing this technique to train your pet (and I hope you don't) then there are existing devices for sale that do exactly what you want - including from the Invisible Fence (R) company.