Steven Pinkert’s Inspiration – the Chicago Museum of Science and Industry’s Million Volt Generator
As a young budding scientist growing up on the Southside of Chicago one of my regular weekend haunts was the Museum of Science and Industry. I was facinated with many of the museums exhibit – particularly those that related to electricity and technology. (I had experimented with electricity and electrical devices as early as the age of 5.)
One of my favorite exhibits at the museum was the million volt discharge by General Electric. They would charge a series of capacitors and then discharge them in series producing an electrical arc several feet long of 1,000,000 volts. As part of the demonstration a block of wood was placed in between the electrodes and the block of wood was shattered by the electrical discharge. The sound was deafening but it was one of my favorite exhibits until it was shut down maybe in the 60s or 70s.
I think it was a fairly high maintenance exhibit and I read somewhere that it was finally shut down because of PCBs in the capacitors.
Steven Makes His Own Million Volt Generator
Steven Pinkert was an avid reader of Popular Electronics magazine and in the July 1964 issue there was a project to build a 3 foot tall Tesla coil that would produce maybe 200,000 volts! At the time I was 13 years old.
So I went though the parts list and to my dismay they called for a lucite coil form for the secondary coil. This was about 3″ in diameter and maybe 3 feet tall. It was way beyond my budget. I worked part time at Nolan’s Radio Repair Shop on 83rd street back then and I don’t think I made more that 2 dollars and hour. So I decided that perhaps a square form out of plywood might suffice even though I was sure that the square form would cause some electrical losses.
So I called cousin Phil and together we hand wound a square and 3 foot long secondary coil with thin enamel coated copper wire and then made a simple square primary, also out of wood. We made capacitors out of aluminum foil and glass and then we needed a high voltage source. I scoured all the junk shops in the area and finally got my hands on an old neon sign transformer – just what the doctor ordered.
We completed the wiring, stood back and plugged it in. After just a little fiddling with the spark gap – It worked! We could hold a florescent light bulb in our hand 3 feet away and it would light up. We could draw maybe a 4-5″ spark from the electrode at the top to ground. We actually kept the Tesla Coil in Phil’s mother basement until she sold her home about 10 years ago. I am going to see if I can hunt down a photograph, but it looked like a crude version of what appears on the magazine cover above.