History of Television

Evolution of Television

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A Short Introduction on the evolution of television

Through out history, television was created by two different types of systems. The first was called a mechanical system named because a metal disk was used. The second system was an electronic system; this system is used today. In the beginning developmental stages of television, TV was invented in secret. The development of it was conducted by most radio stations was done in secret because the radio at that time was an entertainment standard which most believed TV could never compare to. TV at first was not a big profiter, so it was not thought of as important invention. It slowly began to grow with the help of various inventors into something more. Few began to sense that it would be a greater source than the radio for information and entertainment. Today it has become an important part of our lives. It continues to grow. Television is now more interactive as it is being combined with the Internet and we are actively involved with it every day of our lives.

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Time Line of the History of Television

1923

1956

1883	1897	1905	1908	1923
Discovery of the electrical resistance of selenium varying with light; created the technical possibility that pictures could be translated into electronic signals.	The Cathode Ray Tube (CRT) was developed; with this, improvements were made in amplifying the electronic signals. There was still a roadblock in developing a device to transmit changing images due to the slow reaction of selenium to light. Television was still far in the future at this point.	The photoelectric cell was introduced as a replacement for selenium. Albert Einstein used quantum theory to explain the photoelectric effect. Nevertheless, the task of achieving the speed and coordination between transmitter and receiver to broadcast moving pictures was going to be difficult.	The use of the Cathode Ray Tube (CRT) in transmission could render the whole system electronic.	Vladimir Zworykin filed a patent for electronic television but the pictures he obtained were of such bad quality that his employers at Westinghouse chose not to pursue his project.
1925	1928	1930s	1930s	1931
The first attempts at commercial television occurred in the U.S. and in England.	There were about 15 American television stations. The pictures attempted for broadcast were mostly experimental. Disappeared in 1933 because of poor picture quality. The need for an adequate scanning system was necessary.	CRT has were improved enough to be used in transmission. Zworykin became head of RCA's lab. RCA realized shortly after that commercialization was best years away and they cut back on funding for television research.	Zworykin and Philo Farnsworth made advancements. Farnsworth came up with a system that could transmit only bright pictures but incorporated elements of a superior scanning system.	Despite decades of effort, there was a limit to how rapidly a mechanical scanner could work. The television in 1930 was fuzzy and the picture jumped. It was estimated that 7 million pictures per second would have to be transmitted for good quality.
1935	1939	1941	1946	1956
RCA announced a 1 million-dollar plan to develop television. Having the television ready to market was in an electronic company's best interest because radio sales were tapering off.	Leading electronic firms spent 13 million on the commercialization of television and still had no sales. Research costs increased because the competition was highly intense. RCA and Philo Farnsworth realized they both held patent positions and television depended on cross licensing. They reached an agreement.	The Federal Communications Commission settled on the 525 line screen, 30 frames per second, and 6 megahertz band width standard that is in use today for government regulation standards. 30 stations were licensed but World War II delayed the spread of television.	The synthesis of four different designs led to a mush better receiver.	Half of American households had a television set and thus marked a piece of technological history.

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Key Terms:

The Cathode Ray Tube: Served a variety of functions. The most important one was its use in displaying the waveform of electronic signals; this was important in the development of radio as well.

The major holdup in producing an acceptable picture is the need for an adequate scanning system.

A television camera must scan a picture in small blocks, usually from left to right in a series of lines.

Unlike movies where the eye is fooled by a series of still photos, a television picture is changed block by block.

If the blocks are small, the scanning mechanism must move very quickly.

Otherwise, the blocks would be changed too slowly for the eye to be fooled, and the picture would appear to jump.

The Purpose of Scanning: To send an electronic signal that tells the receiver how dark a particular block should be.

The use of very small blocks is necessary if the picture is to be well defined.

Experiments with electromechanical scanning devices began in the 1880's.

In these, mechanical power moved the scanner from block to block.

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Inventors:

John Logie Baird

In London, Jan 1926, he developed the very first demonstration of actual television. He applied Nipkow's scanning disc idea and used it with the latest in electronics to create this demonstration. His system "the Baird standard" was 30 lines per frame, at 12.5 frames per second. From the years 1927-1929, he developed color television and was able to transmit the image of a face across the Atlantic. He was never able to play pictures back, however. In 1929, he started broadcasting television for BBC, and in 1930, the first simultaneous sound and vision was played. Bairds disks are "the first recordings of television in the world".

Philo T. Farnsworth

Philo's interest in the technology of television and television photo history first developed in his youth. He was interested in developing electronic television. Philo never used anything but a cathode ray tube as a receiver. He used rotary generators to produce his early scanning voltages. In 1927, he was able to created "the only operating camera tubes in the world". He transmitted an "image" from one of his early camera tubes. At the age of twenty, he created the first moving image of a burning cigarette, and developed the first motion picture film. The film was a movie of a hockey game. In Aug 1930, he received a patent, made RCA sign a patent with him, and moved to keep pace with the development in technology to further work on his invention. In 1934, he demonstrated an electronic television and then sold his patents to RCA. RCA took his invention to the New York World fair and it was announced the "Birth of Television. Philo is also known for a number of other inventions. He invented the fax, a baby incubator, the gastroscope and electronic microscopes.

C. Francis Jenkins

He held a demonstration on "the projection of motion pictures by television to member of the Federal Radio Commission." What he had done was create a new television receiver. " He applied for a patent on a cell persistence transmitter on July 16, 1928. " He is noted as a major developer of the mechanical television system. On April 17, 1927, he broadcast the Secretary of Commerce Herbert Hoover who was speaking in Washington DC, and sound and picture were received in NY city and in Whippany New Jersey. This was very successful broadcast because it had connected three city networks.

Paul Gottlieb Nipkow

He received what is known as the master TV patent on Jan 6, 1884. He showed a means of systematic scanning images into elemental points with a perforated disc. He developed the very first mechanical television system.

Vladimir Zworykin

He was RCA's chief inventor. He worked with a cathode ray transmitter, and received a patent for electronic technology and received the most credit for the invention of electronic television.

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The term "television" and old names for it:

A science writer named Hugo Gernsback created the term "television". There were a few other ideas for what we now call television and here are some of them: "Radioscope"

"Motion Picture by Ether Waves"

"Radiovision"

"Telephone Eye"

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Sources:

www.songs.com/philo/prehisto.html

http://members.aol.com/mcleandon/majorad.html

http://members.aol.com/mcleandon/tv_1strx.html

Abramson, Albert The History of Television, 1880-1941. McFarland & Company, Inc. Jefferson, North Carolina and London 1987

Cross, Gary & Szostak, Rick. Technology and American Society: A History. Prentice Hall, Englewood Cliffs, NJ 1995.

Ritchie, Michael Please Stand By. The Overlook Press, Woodstock, NY 1994

Stross, Randall E. Technology and Society in Twentieth Century America. Wadsworth Publishing Company, Belmont California 1989.

Andrea Berte, Gail Osgood