28 January 2010

Radio



The invention: The first radio transmissions of music and voice
laid the basis for the modern radio and television industries.
The people behind the invention:
Guglielmo Marconi (1874-1937), an Italian physicist and
inventor
Reginald Aubrey Fessenden (1866-1932), an American radio
pioneer
True Radio
The first major experimenter in the United States to work with
wireless radio was Reginald Aubrey Fessenden. This transplanted
Canadian was a skilled, self-made scientist, but unlike American inventor
Thomas Alva Edison, he lacked the business skills to gain the
full credit and wealth that such pathbreaking work might have merited.
Guglielmo Marconi, in contrast, is most often remembered as
the person who invented wireless (as opposed to telegraphic) radio.
There was a great difference between the contributions of Marconi
and Fessenden. Marconi limited himself to experiments with
radio telegraphy; that is, he sought to send through the air messages
that were currently being sent by wire—signals consisting of dots
and dashes. Fessenden sought to perfect radio telephony, or voice
communication by wireless transmission. Fessenden thus pioneered
the essential precursor of modern radio broadcasting.
At the beginning
of the twentieth century, Fessenden spent much time and energy
publicizing his experiments, thus promoting interest in the
new science of radio broadcasting.
Fessenden began his career as an inventor while working for the
U.S. Weather Bureau. He set out to invent a radio system by which
to broadcast weather forecasts to users on land and at sea. Fessenden
believed that his technique of using continuous waves in the
radio frequency range (rather than interrupted waves Marconi had
used to produce the dots and dashes of Morse code) would provide
the power necessary to carry Morse telegraph code yet be effective
enough to handle voice communication. He would turn out to be
correct. He conducted experiments as early as 1900 at Rock Point,
Maryland, about 80 kilometers south ofWashington, D.C., and registered
his first patent in the area of radio research in 1902.
Fame and Glory
In 1900, Fessenden asked the General Electric Company to produce
a high-speed generator of alternating current—or alternator—
to use as the basis of his radio transmitter. This proved to be the first
major request for wireless radio apparatus that could project voices
and music. It took the engineers three years to design and deliver
the alternator. Meanwhile, Fessenden worked on an improved radio
receiver. To fund his experiments, Fessenden aroused the interest
of financial backers, who put up one million dollars to create the
National Electric Signalling Company in 1902.
Fessenden, along with a small group of handpicked scientists,
worked at Brant Rock on the Massachusetts coast south of Boston.
Working outside the corporate system, Fessenden sought fame and
glory based on his own work, rather than on something owned by a
corporate patron.
Fessenden’s moment of glory came on December 24, 1906, with
the first announced broadcast of his radio telephone. Using an ordinary
telephone microphone and his special alternator to generate
the necessary radio energy, Fessenden alerted ships up and down
the Atlantic coast with his wireless telegraph and arranged for
newspaper reporters to listen in from New York City. Fessenden
made himself the center of the show. He played the violin, sang,
and read from the Bible. Anticipating what would become standard
practice fifty years later, Fessenden also transmitted the sounds of a
phonograph recording. He ended his first broadcast by wishing those
listening “a Merry Christmas.” A similar, equally well-publicized
demonstration came on December 31.
Although Fessenden was skilled at drawing attention to his invention
and must be credited, among others, as one of the engineering
founders of the principles of radio, he was far less skilled at
making money with his experiments, and thus his long-term impact
was limited. The National Electric Signalling Company had a fine
beginning and for a time was a supplier of equipment to the United
Fruit Company. The financial panic of 1907, however, wiped out an
opportunity to sell the Fessenden patents—at a vast profit—to a corporate
giant, the American Telephone and Telegraph Corporation.
Impact
Had there been more receiving equipment available and in place,
a massive audience could have heard Fessenden’s first broadcast.
He had the correct idea, even to the point of playing a crude phonograph
record. Yet Fessenden, Marconi, and their rivals were unable
to establish a regular series of broadcasts. Their “stations” were experimental
and promotional.
It took the stresses of World War I to encourage broader use of
wireless radio based on Fessenden’s experiments. Suddenly, communicating
from ship to ship or from a ship to shore became a frequent
matter of life or death. Generating publicity was no longer
necessary. Governments fought over crucial patent rights. The Radio
Corporation of America (RCA) pooled vital knowledge. Ultimately,
RCA came to acquire the Fessenden patents. Radio broadcasting
commenced, and the radio industry, with its multiple uses
for mass communication, was off and running.






Guglielmo Marconi

Guglielmo Marconi failed his entrance examinations to the
University of Bologna in 1894. He had a weak educational background,
particularly in science, but he was not about to let
that—or his father’s disapproval—stop him after he conceived
a deep interest in wireless telegraphy during his teenage years.
Marconi was born in 1874 to a wealthy Italian landowner
and an Irish whiskey distiller’s daughter and grew up both in
Italy and England. His parents provided tutors for
him, but he and his brother often accompanied their
mother, a socialite, on extensive travels. He acquired
considerable social skills, easy self-confidence, and
determination from the experience.
Thus, when he failed his exams, he simply tried another
route for his ambitions. He and his mother persuaded
a science professor to let Marconi use a university
laboratory unofficially. His father thought it a
waste of time. However, he changed his mind when
his son succeeded in building equipment that could
transmit electronic signals around their house without wires, an
achievement right at the vanguard of technology.
Now supported by his father’s money, Marconi and his
brother built an elaborate set of equipment—including an oscillator,
coherer, galvanometer, and antennas—that they hoped
would send a signal outside over a long distance. His brother
walked off a mile and a half, out of sight, with the galvanometer
and a rifle. When the galvanometer moved, indicating a signal
had arrived from the oscillator, he fired the rifle to let Marconi
know he had succeeded. The incident is widely cited as the first
radio transmission.
Marconi went on to send signals over greater and greater
distances. He patented a tuner to permit transmissions at specific
frequencies, and he started theWireless Telegraph and Signal
Company to bring his inventions to the public; its American
branch was the Radio Corporation of America (RCA). He not
only grew wealthy at a young age; he also was awarded half of
the 1909 Nobel Prize in Physics for his work. He died in Rome
in 1937, one of the most famous inventors in the world.

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