Perimeter Bear Alarm Fence

This is a perimeter fence to sound an alarm if a large critter enters the camp. We generally use motion detectors, but they are not adequate for a polar 24hour sunlight scenario and well-insulated polar bears. The alarm on this fence sounds if either the circuit is broken or any fence poles are overturned.

I found the basic design on Jerry Kobalenko's website: http://www.kobalenko.com/ and Jerry also kindly answered my questions. Jerry's blog and books are an absolute goldmine of information