A somewhat different problem exists here in the world of television broadcasting. Our transmitters are connected to the antennas by generally over 1000 feet of coaxial line, or waveguide. The coaxial line is made of rigid copper, in twenty foot lengths bolted together, usually 6 to 8 inches in diameter, with an inner conductor that is about 2 to 3 inches in diameter. These coaxial lines are made of pure copper, and each section weighs in excess of 150 pounds. Waveguide is made of aluminum, and will have a rectangular cross-section, generally measuring 8 inches, by about 34 inches, and will weigh up to 200 pounds per 20-foot section.
Needless to say, both coaxial line, and waveguide are magnets for the thieves.........however, a typical television transmitter generates somewhere in the neighborhood of 50,000 to 75,000 Watts of RF energy, and RF acts much differently on the human body than electricity. When a thief attempts to saw through the transmission line, as soon as the saw penetrates the outer casing into the airspace between the outer and inner conductors, the RF energy begins to radiate out of the slot made by the saw........the results are comparable to placing the human body into a microwave oven that is producing 50,000 times the power of the average microwave, and it literally "cooks" the thief from the inside out.......it is not a pretty (or quick) way to die, and it will continue until the saw actually contacts the inner conductor which will trip the transmitter off due to a VSWR fault........however, just like NHSparkies example........the transmitter will reset the fault automatically, and make two additional attempts to return to "on-air" status, before the protection logic shuts it down completely.
Needless to say, by that time, what is left of the thief looks surprisingly like what a pig looks like during a "whole pig roast"......not a sight for someone with a weak stomach......
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