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Have you ever been to Griffith Observatory in L.A., California?  We have a Tesla Coil that we obtained in 1935 from a carnival.  This has always been one of the most popular exhibits in the Observatory.  We demonstrate the T-Coil by having patrons hold a fluorescent tube (which lights up, of course) as we fire up the "lightning machine".  We also demonstrate an "electric kiss" by having couples make a small gap between their lips as one of the partners touch a nail near the T-Coil (A tiny spark jumps from lip to lip).  There are a few other things we do, and I'm always trying to come up with something new. Do you have any suggestions? Thank you!

P.S. I always make people listen to my history of Tesla before I show them any tricks.  Unfortunately, most people don't care about the history; they just want to see the "lightning".  This is the reality, and that's why I'm asking for any "tricks".  When I do tricks, the people get more interested and even listen for a few seconds.

I haven't been to the Griffith Observatory but understand from an associate in Burbank that your Tesla coil is an impressive one. As for novel demonstrations, while there are a number that have been mentioned in the literature most of them involve direct connection to the oscillator. They include such things as the luminosity of a fine wire on a dielectric plate, glow discharge between two rings, brush discharge between two parallel wires, brush discharge through a dielectric plate, rotating pinwheel, and the lighting of a vacuum tube between two plates. Most of these can be traced back to the lectures of 1891-93, in particular the "Experiments With Alternate Currents of High Potential and High Frequency" [Inventions, Researches and Writings of Nikola Tesla] delivered by Tesla in 1892 before the Institution of Electric Engineers in London.

With an oscillator such as yours, it might be best to focus on those demonstrations that can be performed without direct physical contact. While the lighting of a fluorescent tube is a tried and true standard, it is possible to greatly improve the performance of this demonstration by adding a tuned circuit that is adjusted to vibrate in harmony with transmitter. This typically consists of a single layer wire coil or solenoid with the upper end connected to a metal plate and the lower end connected to an earth ground. The tube is inserted into the ground lead. Fine tuning can be accomplished by adjusting the size of the elevated plate which can be made of aluminum foil suspended from a light weight wooden "T" shaped frame. As an alternative to the fluorescent, it is possible to light a small incandescent lamp by connecting it to a shorter secondary coil wrapped around the solenoid. If you really want to get tricky, connect a small DC permanent magnet motor to the secondary through a silicon diode bridge rectifier.

While the circuits described above are quite simple, the difficulty arises in getting them in tune with the transmitter. You might want to enlist the assistance of a local amateur radio operator with this. Also, I would like to recommend an inexpensive booklet titled Tesla Oscillator and Fluorescent Tube Driver that covers this very subject. Another good source of information is the Tesla Coil Builders Association, 3 Amy Lane, Queensbury, NY 12804-9432.

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