By Norris Chambers

             In the late thirties a thing called “electric fence” began to get popular among those farmers who were able to buy one. They used a six volt automobile battery for power. The battery could be charged in a number of ways – a wind charger, a gasoline engine with a generator, by swapping it with one in a car or tractor or taking it to a service station with a battery charger. The little machines didn’t require much power and a battery charge would last for several days.

            The first chance we got Clifton and I removed the cover of one and looked to see how it worked. It was pretty simple. There was a rather large hair spring on the same shaft as a little flywheel with a metal tab on the shaft and an electromagnet that pulled it against the spring when electricity actuated the magnet.  The spring pulled the shaft and wheel back toward the magnet and just before it touched the magnet it hit a switch that turned the power on that operated the electromagnet. The magnet pulled the wheel around again, breaking the connection that the switch provided. Then the spring eventually stopped the rotation of the wheel and it came back, repeating the process. This process continued at an adjustable rate of 1 to 4 seconds between contacts. Each time the switch connected the magnet and moved the wheel it passed current through a winding on a spark coil and a high voltage was applied to the one wire that served as a fence.

            The grounded, or negative, side of the fence was connected to a metal rod driven into the ground. The output of the fencer was connected to a single wire that was mounted on insulators and served as the fence. The height above ground that the wire was strung depended on the type of animals that were to be confined by it. For hogs it had to be very low; perhaps ten or twelve inches. For cattle about three feet and for horses about four.

            Every time the switch closed an electric charge was applied to the fence wire and any animal touching it received a powerful shock. Any kind of bare wire could be used for the fence. Regular barbed fencing wire worked well. Before any animals were put in an area using the electric fence they were placed in a training pen with the electric wire being the only fence. A few attempts to crawl under the wire soon taught them not to touch a wire. Hogs learned quicker than any animal. Horses and goats, or sheep, were fast learners. Cows were the slowest learners but when they learned they remembered well. There was one problem. The fencers cost more than many farmers could afford.

 I had just opened my country radio shop and my electronic training convinced me that I could build a cheaper fencer that would work. Clifton and I bypassed the blacksmith shop and went to my crude radio shop to see what we could do. Instead of the complicated spring and flywheel to give the electric pulses we got the idea of a marble rolling up an incline and rolling back down to actuate the switch. For the magnet and coil we substituted an old Model T Ford ignition coil. It already had a magnet core and vibrating points. All we had to do was reposition the points and find a metal tube and large marble (the final model used a steel ball since it was heavier) and arranged them so the coil pulled the arm and kicked the ball up the tube, which was mounted on an incline, and repeated the action when it rolled back down. When the switch was closed for a very short time it sent a spark from the coil to the fence wire and several thousand volts was applied for animal discouragement. The idea worked great. All we had to do to set the rate of electric pulses was raise or lower the incline of the pipe.

            We had a machine that worked even better than the bought ones because the ignition coil was stronger than the ones in the manufactured machines. Model T coils were available from wrecking yards for practically nothing and steel balls were everywhere around oil wells. The repair kits for the pump overhauls came with new balls and the old ones were thrown away. They were free for picking up and cleaning. There was very little cost involved in building the fencers. We had a winner! We sold dozens of our machines to farmers for eight dollars. The store-bought machines were at least twenty dollars.

            And we had fun building them. If you’ve never built an electric fencer you don’t know how much fun you have missed! Maybe you ought to build one!