File:Small Tesla coil kit 1918.jpg

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Summary

DescriptionSmall Tesla coil kit 1918.jpg	English: A Tesla coil, a resonant transformer circuit invented by Nikola Tesla that generates very high voltage, radio frequency alternating current electricity at low current levels. This example is an educational kit for use in classroom demonstrations. It probably produces on the order of 100 kV at frequency of around several hundred kilohertz. It consists of a step-up transformer (right) which produces several thousand volts, a pair of Leyden jar capacitors (center) a spark gap (not visible) and the resonant "oscillation transformer", (left). The high voltage is produced between the ends of the coil and jumps across the gap between the wires above the coil.
Date	1918
Source	Retrieved April 9, 2015 from Sidney Gernsback, Harry Winfield Secor (1918) Experimental Electricity Course in 20 Lessons, 2nd Ed., The Experimenter Publishing Co., New York, p. 116, fig. 11 on Google Books
Author	Sidney Gernsback

Licensing

Public domain	This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.	United States
	This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.