In 1891, Tesla invented the device that became known as Tesla’s oscillator of high-frequency currents, Tesla’s resonant transformer or Tesla Coil. It is used for generating high-voltage and high-frequency currents. The currents produced by Tesla Coil have frequencies in the range of several tens of thousands Hertz, and are scientifically called Tesla Currents.

Tesla used this apparatus to generate lightning and in his research of electrical lighting, phosphorescence, the generation of Roentgen X-rays, electro-therapy and long-distance wireless transfer of electrical signals and energy. Modern transformers, based on Tesla coil can also reproduce music.

Unlike Tesla’s Oscillating Transformer with output voltage of 500 kV, this Tesla Coil has output voltage of 120 kV, and in the case of this exhibit visitor can touch electrical discharge. Due to „skin effect“ it is safe to touch electrical discharge and let high-voltage and high-frequency electricity to flow over the surface of the skin.