• It consists of a rectangular iron core, standing 15 cm tall. The primary coil has a fixed number of turns and is connected to an AC power supply. The iron core has its top side hinged allowing the secondary coil to be easily changed. One can vary the number of turns and connect the coil to a small lamp, to an oscilloscope or, to a multimeter. For example, two resistors of different values can be connected around one side of the iron core and the difference in voltage across them measured.

    Primary coil has 490 turns, and the secondary has 35.

    The Small Transformer

  • Two copper pipes mounted on a cart and connected to a neon sign transformer (15,000 volts/60ma). The spark starts at the bottom of the ladder, where the small spacing encourages elctrical breakdown. The discharge heats the air, which begins to rise. Because the discharge is a region of least electrical resistance, the spark continues along that path, which continues to rise. At the top of the ladder the discharge path becomes so long that its resistance is greater than the resistance of the shorter path at the bottom of the ladder.

    Jacob's Ladder

    Click here to see Jacob’s Ladder in action.

  • The Tesla coil is an air-core transformer with primary and secondary coils tuned to resonate. The primary and secondary coils function as a step-up transformer which converts a relatively low-voltage high-current signal to a high-voltage low-current signal at high frequencies. It demonstrates the fundamental principles of high frequency electrical phenomena. It illustrates the principles of the ionization of gases and the behavior of insulators and conductors when in contact with high frequency electrical fields. There are more than a dozen demonstrations that can be performed with this Tesla coil.

    The Tesla coil was developed by Nikola Tesla to transmit electrical power without wires. An antenna would be used to pull the transmitted electrical energy into the electrical system. It can be considered a simple radio transmitter, operating within a broad range of high frequencies, which transmits power rather than information.

    Tesla Coil

    Tesla Coil

    Tesla Coil

    Click here to see the Tesla Coil in action!

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