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Wield the power of lightning with this modern design that would make Nikola himself proud.
One hundred years ago, from a mountain top in Colorado, Nikola Tesla transmitted electrical power with his famous Tesla coil for a distance of 25 miles without wires. That high voltage experiment in the wireless transmission of power is as fascinating today as it was back then. The majority of the Tesla coils being built today are of conventional design, depending on the use of line-operated step-up transformers to generate the necessary high voltage for the Tesla coil's primary circuit. And rightfully so. After all, they are based on a time-proven design, but it can be very dangerous or even fatal if the Tesla coil's primary is accidentally touched!
Our solid-state DC Tesla coil eliminates the line-operated, high-voltage transformer, making it less dangerous to operate and experiment with. However, there's still the possibility of shock if the primary tuning capacitor is accidentally touched while the circuit is in operation or even when the power is turned off.
There is one other aspect of our Tesla coil that is different from the conventional design, and that's the DC part. In a standard coil design, the maximum spark length obtained from the secondary coil is primarily determined, in an efficient system, by the AC-- input power to the Tesla system. In a DC coll, the input energy is applied in steps and stored in the primary's tuning capacitor until the capacitor's voltage reaches a level sufficient to jump the spark gap. The DC coil doesn't spew out a continuous spray of sparks like the conventional coil but sends out snappy sparks in a slow motion, machinegun like manner. Our DC Tesla coil only consumes a few watts of power but can output a 6- to 8-- inch spark to ground.
About the Circuit. The schematic diagram of the Solid-State Tesla Coil is shown in Fig. 1. The circuit is built around a 555 oscillator/timer (IC1); a pair of IRF9130 P-channel HexFETs (Q1 and Q2); a gaggle of diodes, both 1N4007 and 1N5401 types (D1-D94); three transformers-T1, a 25-VCT, 2-amp unit, and T2 and T3, a pair of auto ignition coils; a couple of hand-wound coils (L1 and L2); and several...