Thursday, January 28, 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.

1 comment:

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