Hi, I have a Parmak Mark III, and after an extended period of disuse; I found the unit had failed. Upon disassembly, it appeared that ants had nested inside causing a short that fried a fuse and burned off the ground connection to the fuse block. There may be additional damage, as the soldered connections do not allow component isolation for testing. I don't know if the unit is worth repairing or should simply be replaced. The only reason that I am considering repair is my knowledge that most modern equipment is not as good as the old stuff. Right now, I just have 120VAC wired to my electric fence; and, have considered using a step-up transformer from a salvaged microwave oven as a power source. With some background in electronics, it seems to me that the transformer's high voltage, low current output would accomplish the same function as a charger, without the pulsation of some. Any enlightenment that you may provide, to include a repair estimate, would be appreciated.