Admin, from that Otto Schmidt link you posted comes this bit. I repeat: Kids, don't try this at home! :-O
"You know how kids get a little money for gifts? I saved up my Christmas presents and bought a second-hand pole pig for $25.00. That's a 2000-watt line transformer that goes out on the power pole and steps down the 2000 volts to 110 or 220. I discovered that if I climbed onto the pole and moved the wires so that the line for my father's store ran into our house, I had 220 volts in my room. When I connected the thing in parallel for 110 volts, I found that this transformer was sturdy enough so that, for a few minutes, it would take 220 volts on its 110-volt output and step it up not to 2200, but to 4400 volts at about 5 kilovolt-amperes.
"With 5 kilovolt-amperes, a rotary spark gap, and a suitable coil, you've got the makings of some really high-voltage stuff. And so, I made my own Tesla coil, using automobile starter cable for the primary winding. I wound the secondary coil with number 40 silk covered wire and connected them in series. The question now was how to tune the transformer to the right frequency. How do you tune that much current at that voltage?
"I simply borrowed my mother's dishpan, put mason jars in it with lead electrodes in them and added salt water. I tuned the thing by adjusting the amount of saltwater until it resonated. To lower the frequency, add a little saltwater; to raise it, take some away. Once in resonance, that thing really went.
"I needed a rotary spark gap, so I placed some electrodes around a thick old Edison phonograph record and ran it with a motor I had rewound. The thing roared around and broke the gaps and produced about 200,000 volts at 150 to 200 kilocycles. It was great fun.
"What was marvelous was to assemble an insulated stool, made by placing a breadboard atop four big, strong, old milk bottles, then another layer of milk bottles, and another breadboard. I carefully crawled onto the stool and placed my hand on the ball, and oh, boy, was that ever fun! Your hair stood on end, sparks a couple of inches long came out of your nose and ears and off the tips of your fingers.
"I demonstrated this to my pals, who turned out the lights to better see the sparks. My mother heard the roar of the spark gap and came in to investigate. When she opened the door and found me standing there surrounded by fire, she fainted dead away. I was in the doghouse for awhile, but at least I had my 200,000-volt Tesla coil."
Great page, thanks.
