Answer the following questions:

1. Why were there many disputes about who was solely responsible for the invention of radio?

2. What can you say about Maxwell’s theoretical physical research?

3. What was Hughes contribution to the electromagnetic waves?

4. What did Hertz proved in his experiments?

5. What kind of radio system did he present?

6. How did Tesla contribute to electrical science?

7. What kind of apparatuses did he produce in the New York laboratory?

8. Where was transmission and radiation later used?

9. What kind of wireless signals did Tesla receive by 1897?

10. What system did he establish for other scientists?

12. Invention of radio. Part II.

Beginning in the early 1890s, Olexander Stepanovich Popov conducted experiments along the lines of Hertz's research. In 1894 he built his first radio receiver, which contained a coherer. Further refined as a lightning detector, he presented it to the Russian Physical and Chemical Society on May 7, 1895 — the day has been celebrated in the Russian Federation as "Radio Day". The paper on his findings was published the same year. Popov had recorded, at the end of 1895 that he was hoping for distant signalling with radio waves.

In November 1894, the Bengali Indian physicist, Jagdish Chandra Bose, demonstrated publicly the use of radio waves in Calcutta, but he was not interested in patenting his work. In 1894, Bose ignited gunpowder and rang a bell at a distance using electromagnetic waves, showing independently that communication signals can be sent without using wires. Bose was not interested in the commercial applications of the experiment's transmitter. He did not try to file patent protection for sending signals. Though he did not file any patents for transmission, he is recognized for contributing to the development of radio.

Guglielmo Marconi, Italian-Irish electrical engineer and Nobel laureate known for the development of a practical wireless telegraphy system. In 1894 he read about the experiments that Hertz did in the 1880s, and about Nikola Tesla's work in the just-published book Inventions, Researches and Writings of Nikola Tesla. It was at this time that Marconi began to understand that radio waves could be used for wireless communications. Marconi's early apparatus was a development of Hertz’s laboratory apparatus into a system designed for communications purposes. At first he used a transmitter to ring a bell in a receiver in his attic laboratory. He then moved his experiments out-of-doors on the family estate near Bologna, Italy, to communicate further. Marconi transmitted radio signals for about a mile at the end of 1895. Marconi's reputation is largely based on these accomplishments in radio communications and commercializing a practical system. The transmitter was an antenna circuit, with an aerial plate and a ground plate, and a spark gap. Induced signals in the circuit were caused to discharge through a spark gap, producing oscillations which were radiated. The receiver contained an antenna circuit, an aerial plate and a ground plate, and a coherer.

In 1943 Marconi's numerous other radio patents were resolved by the U.S. Supreme Court, who overturned most of these. The court decision was based on the proven prior work conducted by others, such as by Tesla, Oliver Lodge, and John Stone Stone. Marconi supporters have stated that Marconi was not aware of the works of Nikola Tesla in the United States. By 1895, Marconi introduced to the public a device in London, asserting it was his invention. Despite Marconi's statements to the contrary, though, the apparatus resembles Tesla's descriptions in the widely translated articles. Tesla advanced the longitudinal electromagnetic waves (such as those that occur in waves in plasmas) through the medium would be used, as he theorized that they would be practically lossless. His devices can be driven to produce either transverse or longitudinal waves.

There is also the relevance of Tesla demonstrations of the remote-controlled boat (with its internal rotating coherer) as well as Tesla's public lecture demonstrations. Besides his intention to transmit wireless signals of intelligence, he proposed to transmit electric power via electrical conduction through the earth and the upper atmosphere, as well as in between them both. Tesla’s proposed wireless transmitter utilized a resonant transformer to apply a very high voltage of high frequency between the earth and a large elevated conductor, as discussed earlier. The identity of the original inventor of radio, at the time called wireless telegraphy, is contentious. The key invention for the beginning of "wireless transmission of data using the entire frequency spectrum" has been attributed to various inventors and researchers.