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Radio Essay Research Paper Radiowave technology is

Radio Essay, Research Paper

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 (White). His theory mainly had to do with light waves, but fifteen years later, a German physicist named Heinrich Hertz was able to electrically generate Maxwell s rays 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 America s move into the Information Age (White).

The invention of radio is commonly credited to Guglielmo Marconi, who, starting in 1895, developed the first wireless 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 (White). 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 (White).

Radio works in a very complicated way, but here s a more simple explanation than you ll get from most books: Electromagnetic waves of different wave lengths are produced by the transmitter, and modulations within each wavelength are adjusted to carry encoded 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 (Fenton). 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 a radio receiver in every home in 1916, although the real potential of radio wasn t realized until after World War I (White).

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). Fessenden s first broadcast was for entertainment, but radio wasn t to be used widely as such for some time. WWI proved radio s value to the army, and later its commercial uses were realized by entrepreneurs who encouraged the public to buy receivers or radios (White).

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 (Fenton). 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 20s. As its popularity increased, commercial radio began to take off. Radio KOW in San Jose Ca. was the first commercial broadcast station to begin regular programming as early as 1912. 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 (White).

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 (Fenton).

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 radio systems are more expensive, yet not impossibly expensive for a working middle-class citizen. This availability to the majority of the population has increased use of radio devices, raising awareness of local, national, and global news. Unfortunately, this increased use also created a new part of society, which is lazy and addicted to television in many cases (Fenton).

Radio is now a very widely used technology. Almost everyone uses it to communicate and to get news. Through both television and public radio news people are able to find out about things going on all over the world. Cellular phones, Citizen Band (CB) radios, two-way radios (Walkie-Talkies), satellite phones, and cordless phones all help people to communicate from places where phone lines are not necessary or cannot be laid (Fenton). Commercial companies use it for advertisement. Most frequently, people use the radio or television for entertainment and relaxation. People watch engaging programs broadcast over radio waves and received by television sets or satellite dishes. They laugh at comedians from around the world, are amazed by incredible action, scared out of their wits by horror and suspense, and cry with tragedies, all portrayed in a fashion much like that of the Elizabethan theater magnified ten thousand times over. Everyone wanted a radio to listen to when it came out (Fenton). Several years after television was invented, everyone wanted one of those too. Since then, radio entertainment has become as much a part of American culture as the hot dog. Now commercial ships and aircraft use radio for navigation as well. Almost everyone in the U.S. uses radio today and most find it very helpful and entertaining.

The U.S. Government uses radio as well. Through years of research and development the military discovered the use of the radar bands (a group of waves within the electromagnetic wavelengths designated as radio) of radio for detecting objects. They also use radio waves for telemetric navigation (triangulating position by transmitting to three points and calculating the distance) (Fenton). Since the 60s it has enabled outer space missions to be undertaken, allowing for ground units to assist in the delicate maneuvers of space travel and play the role of ground based environmental information service. Pilots of separate space vehicles also can use radio to simultaneously communicate and calculate their distance from each other by the delay time in transmissions. NASA uses them to receive information from space probes, and to talk to shuttle crews (Fenton).

Overall, radio is a marvelous invention and there are many inventive uses for it. The good uses and attributes of radio include: Communication with anywhere instantly, new technologies enabled, news source, profitable advertising medium, very entertaining. Radio is one of the most useful things ever discovered and used by man. It enables people to transfer information incredibly quickly, so deals, research, and personal business around the world can all be done without having to travel too far.

Radio has helped the US economy and helped all citizens become more informed about world issues and news. It has made life much easier for everyone and aided us all in obtain better knowledge about our surroundings. It has advanced our science and knowledge past our own planet, and assisted in furthering our technology (Fenton). On the other hand, we all could become detached from the world with the ease given us by the technology we have created. Advances such as television, while having the ability to help us by making us more aware, entertaining, and educating us, also have proved (with overuse) to become a bad habit and capable of causing atrophy of the imagination. Radio has shown us, as many inventions do, what great moderation and responsibility we must use with any new discovery.

As far as the future of radio is concerned, I do believe that radio as we know it today is going to have to really change and expand to keep up with today s changing technologies or radio may become extinct. I think that we are far from that point now, however, with the internet and digital television, there are now easier ways of getting music and news in many quick, advertisement free ways.

References

Fenton, Brian C. Radio. Compton s Interactive Encyclopedia CD

1994 Compton s New Media Radio Infopedia 2 CD

White, Thomas E. United States Early Radio History:

Articles and Extracts United States Early Radio History. www.ipass.net whitetho/index.html (29 Nov. 1998).




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