Radio: Making Waves in America

Radio: Making Waves in America

Radio-wave technology is one of the most important technologies used by man. It has forever changed the United States and the world, and will continue to do so in the future. Radio has been a communications medium, a recreational device, and many other things to us. When British physicist James Clerk Maxwell published his theory of electromagnetic waves in 1873, he probably never could have envisioned the sorts of things that would come of such a principle. His theory mainly had to do with light waves, but fifteen years later, a German physicist named Heinrich Hertz was able to electrically generate MaxwellХs ТraysУ in his lab. The discovery of these amazing properties, the later invention of a working wireless radio, and the resulting technology have been instrumental to AmericaХs move into the Information Age. The invention of radio is commonly credited to Guglielmo Marconi, who, starting in 1895, developed the first ТwirelessУ radio transmitter and receiver. Working at home with no support from his father, but plenty from his mother, Marconi improved upon the experiments and equipment of Hertz and others working on radio transmission. He created a better radio wave detector or cohere and connected it to an early type of antenna. With the help of his brothers and some of the neighborhood boys he was able to send wireless telegraph messages over short distances. By 1899 he had established a wireless communications link between England and France that had the ability to operate under any weather conditions. He had sent trans-Atlantic messages by late 1901, and later won the Nobel prize for physics in 1909. Radio works in a very complicated way, but hereХs a more simple explanation than youХll get from most books: Electromagnetic waves of different wavelengths are produced by the transmitter, and modulations within each wavelength are adjusted to carry ТencodedУ information. The receiver, tuned to read the frequency the transmitter is sending on, then takes the encoded information (carried within the wave modulations), and translates it back into the sensory input originally transmitted. Many of the men who pioneered radio had designs for it. Marconi saw it as the best communication system and envisioned instant world-wide communication through the air. David Sarnoff ( later the head of RCA and NBC) had a vision of Тa radio receiver in every homeУ in 1916, although the real potential of radio wasnХt realized until after World War I. Before and during World War I, radio was used primarily to send long distance messages across continents and oceans. Reginald A. Fessenden made the first radio broadcast in the U.S. from an experimental station in Brant Rock, Massachusetts on Dec. 24, 1906. It was a Christmas eve program of music, and a speech from the inventor (Marconi). FessendenХs first broadcast was for entertainment, but radio wasnХt to be used widely as such for some time. WWI proved radioХs value to the army, and later its commercial uses were realized by entrepreneurs who encouraged the public to buy receivers or Тradios.У New technologies made more portable, cheaper, radio devices that were much more appealing to the consumer. Advances such as vacuum tubes and regenerative circuits enabled smaller radios, and later transistors and printed circuits further decreased their size. These advances really helped to spread the use of the radio in America. The radio was affordable enough for the public once mass-production began on public-model radios around the late 1910s and early Ф20s. As its popularity increased, commercial radio began to take off. Radio KOW in San Jose Ca. was the first commercial broadcast station to begin Тregular programming as early as 1912.У The station recognized as the first successful commercial broadcaster was KDKA in Pittsburgh Pennsylvania, going on the air in 1920 with the results of the presidential race between Harding and Cox. Their success led to the rapid growth of radio over the next two years, resulting in over 500 licensed stations by the end of 1922. Around the 1970s microcircuits replaced printed circuits. Plastics were put to use in the casing of the components, instead of a heavy wooden covering. Amplifiers of the radio currents enabled modern style speakers to be used to translate electrical impulses and currents into sound. The development of radio throughout the 20th century has led to many new and wonderful uses and products. These include: television, radar, the Global Positioning System of satellites, remote-control, cellular mobile telephones, cordless telephones, and commercial and private satellite communications. The cost of radio devices has also changed American society. Modern radio receivers for purely audio broadcasts are pretty cheap, some types obtainable from dollar stores (for $1 obviously). Televisions, wireless and cellular phones, and other advanced