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Because they do not know or do not care what scientistsвЂ™ laws say is possible, inventors will try things that scientists will not. Inventors, on the other hand, use the laws of nature to find a way to do something. Scientists obtain their objective by discovering the laws of nature. However, after 1920 this industryвЂ™s history is largely one of organizations. So this industryвЂ™s early history is a story of individual inventors and entrepreneurs, many of whom were both inventors and entrepreneurs. None of the major electrical and telephone companies played a role in the formative years of the radio industry. The Structure of the Radio Industry before 1920: Inventor-EntrepreneursДЄs had been true of earlier high-tech industries such as the telegraph and electric lighting in their formative years, what was accomplished in the early years of the radio industry was primarily brought about by inventor/entrepreneurs. However, it is clear that Marconi had far more influence on the shaping of the radio industry than these men did. Although Marconi is widely given the credit for being the first man to develop a successful wireless system, some believe that others, including Nicola Tesla preceded him. His test of what he called the photophone was said to be the first practical test of such a device ever made. Bell, for example, experimented in 1890 with transmitting sound with rays of light, whose frequency exceeds that of radio waves. Several Americans transmitted speech without the benefit of wires prior to 1900. On land in Europe Marconi was stymied by laws giving government-operated postal services a monopoly on message delivery, and initially only over water was he able to transmit radio waves very far. Later he sent them across the Atlantic Ocean.

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A few years later, in 1894, using a different and much superior wireless telegraphy system, an Italian, Guglielmo Marconi, used discontinuous waves to send Morse Code messages through the air for short distances over land. Eight years after HertzвЂ™s discovery, an American, Thomas Alva Edison, took out a patent for wireless telegraphy through the use of discontinuous radio waves. Electromagnetic waves of from 10,000 cycles a second to 1,200,000,000 cycles a second are today called radio waves. Transmission by radiation owes its existence to the discovery in1877 of electromagnetic waves by a German, Heinrich Rudolf Hertz. Because Stubblefield transmitted sound through the air via induction, rather than by radiation, he was not the inventor of radio. Stubblefield, a Kentucky farmer, in 1892. Induction was the method used in the first documented вЂњwireless telephoneвЂќ demonstration by Nathan B. The possibility of transmitting messages through the air, water, or ground via low frequency magnetic waves was discovered soon after Morse invented the telegraph. Morse, developed a telegraph system utilizing a key to open and close an electric circuit to transmit an intermittent signal (Morse Code) through a wire. Assisted by Henry, an American artist, Samuel F. In 1831, an American, Joseph Henry, used an electromagnet to send messages by wire between buildings on PrincetonвЂ™s campus. In 1752, AmericaвЂ™s multi-talented Benjamin Franklin used a kite connected to a Leyden jar during a thunderstorm to prove that a lightning flash has the same nature as static electricity. In 1600, William Gilbert, an Englishman, distinguished between magnetism, such as that displayed by a lodestone, and what we now call the static electricity produced by rubbing amber.

when the Greek philosopher Thales observed that after it is rubbed, amber (electron in Greek) attracts small objects. Scott, State University of West Georgia The Technological Development of Radio: From Thales to MarconiДЄll electrically-based industries trace their ancestry back to at least 600 B.C. The History of the Radio Industry in the United States to 1940Д¬arole E.