I know very little about electronics per se, except for power wiring in houses in the US. The project I have in mind is an electric fence charger. I really do need one because the bears decimate certain parts of my property in their search for food, even if they can't smell any, they think some might be inside that trailer so they tear it apart. I can't afford a commercial fence charger strong enough to deter bears. But I did, think of using an automotive ignition coil with its own independent 12 volt battery. I would connect the charger to the battery as is usual, then I would connect the jolt wire to the spark plug output side of the coil. I would ground the system with strategically placed strips of galvanized sheet metal laying on the ground, all connected with number 12 AWG insulated copper wire, and then back to the negative post on the battery. I assume that as I described it, this would place a continuous draw on the battery, so I assume I would need some kind of timer that would turn the 12 volt input on and off about four times a second. I assume there's very little amperage, but I don't really know. Any advice for me out there?