Haven't messed with them in a long time, but the few I've worked with used an autotransformer or coil where a battery or low voltage was connected across the primary and the fence and a ground were connected across the secondary. A relay supplied power to the coil until it was charged, (usually about a second) and when the relay interrupted the primary, the collapsing field put a big pulse of energy on the wire. Same principle as the ignition system of a vehicle ...and DC powered relay kickback.
Kent/KA5MIR On Saturday 23 December 2006 20:12, Jim Candela wrote: > Peter, > > I am wondering how electric fence chargers work. I once heard that > they pulse the HV on and off. I assume you grounded the coax shield near > your home or barn yet the coax was still hot anywhere it touched the > earth?? I don't see how that could be unless the coax braid was floating, > and the HV pulsing was coupled to the shield from the cable capacitance > per foot (~ 20pf/'). If the shield was grounded that capacitance would > also charge to the peak value of the pulsed DC, and might end up changing > the whole situation should a cow brush up against the wire. The 'danger' > factor of the fence might go up a notch or two this way. > > I'd like to hear more of your electric fence story. > > Regards, > Jim > JKO ______________________________________________________________ AMRadio mailing list List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected]
