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Could you briefly summarize Tesla's invention of radio and the Supreme Court case of Tesla vs. Marconi? Marconi is mistakenly identified in every history book as the inventor of Radio. Thanks.

Of the myriad natural phenomena which manifest themselves in the universe, radio waves fall into a special category: things which cannot be directly observed. This helps to explain why they remained practically unknown until the 19th century when a number of important steps were taken by early investigators who developed techniques for their detection and measurement. This led to the 1886-88 experiments of Heinrich Hertz which firmly established their existence.

Nikola Tesla's contribution to all this involved reworking the primitive radio frequency generators and tuned receiving circuits which his predecessors had developed. The first step was to introduce the coupled tuned circuit into the transmitter design. Some might recognize this as the configuration of the now familiar Tesla coil, with its primary and secondary circuits both tuned to vibrate in harmony with each other. Additional work resulted in the development of receivers which also incorporated two synchronized circuits. Between 1898 and 1903 Tesla was granted 10 U.S. patents covering his work in these areas.

In 1904 Marconi was able to get his own patent using some of Tesla's ideas. The issue of patent infringement by Marconi was addressed in a lawsuit brought by Tesla 1915. Nothing significant resulted from this until 1916 when the Marconi Wireless Telegraph Company of America itself sued the United States for alleged damages resulting from the use of wireless during WWI. 

In 1935 a ruling of the United States Court of Claims essentially invalidated the fundamental Marconi patent because it was anticipated by Tesla.  The U.S. Supreme Court affirmed this ruling on June 21, 1943.  It's worthwhile noting that the following definition of radio was developed as a result of this case:

A radio communication system requires two tuned circuits each at the transmitter and receiver, all four tuned to the same frequency.

Click here to learn more about this interesting chapter in the history of wireless communications, and see also Priority in the Invention of Radio — Tesla vs. Marconi and John Stone Stone on Nikola Tesla's Priority in Radio and Continuous-Wave Radiofrequency Apparatus.

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