The television A television is an electronic device intended for reception and playback of television signals. Usually consists of a screen and controls or controls. The word comes from Greek and Latin TV viewer (agent videoed 'see').Its operation is based on the phenomenon of photo electricity, which is responsible for converting light into electric current in a camera that can transmit high frequency waves to the receiving antennas and is reproduced on the screen of our television .The TV is one of the most everyday appliances.
TELEVISION HISTORY The first really satisfactory devices for imaging were iconoscope, which was invented by Russian-born American physicist Vladimir Kosma Zworykin in 1923, and the image dissector tube invented by U.S. radio engineer Philo Taylor Farnsworth shortly thereafter. On January 26, 1926 was the first time showed the small screen moving images. That day, in a scientific laboratory in London was the first demonstration of what later became known as television. The credit for such magnificent feat was John Logie Baird, a Scottish engineer who devoted his life to perfecting what is television.
Baird had a hit with his hands and he had only to convince the rest of the world how interesting your device. Soon he founded two experimental television stations in partnership with the post office, and thanks to the cable company was the first cable television transmission. The press supported Baird, said he was a visionary and the official radio, the famous BBC, should be replaced by television. The institution, fearful and suspicious changes to the attraction exerted the invention to the public, he rejected all attempts by the inventor to get a broadcast license. Against that, Baird responded with pirate broadcasts violated English law. A kind of TV trout finally, under pressure exerted by the press and the inventor, was accepted by the BBC.
Since 1929, he began to create pilot programs in spite of having thousands of technical difficulties failed to quell public interest in this device emitting almost magical images created at a distance. The majority opinion of the British assumed that it was not long before the TV occupied a privileged place in their homes. Although the long history proved the veracity of what at the time were just wishful thinking, at that time television had one long way to go. Is that the images were emitting the size of a personal card and because of the low resolution of his thirty-scan lines were limited to showing close-ups. Despite their limitations, these early images was possible to recognize individuals and to their changes of expression.
Baird was heading. Already had the contents and with an audience eager to receive them, only the technique was developed for the construction of the televisions. In 1929, three years after the first public issue, and although Baird believed that more needed to be done, the television began to be manufactured in large scale. A year later, about 20,000 units were sold in England and the rest of Europe. Television, as he had imagined John Logie Baird did not last much longer. Soon, the desire to draw ever more revenue from their invention dropped the TV mechanic and replaced by electricity, while the small screen and became a media outlet for proper name of its creator was exiled to less consulted the pages of encyclopedias.
OPERATIONFirst, a camera receives light from the stage, introduced into his system and a series of lenses they lead to several photodiodes located on a CCD chip. That transforms the light from the scene in a video signal. At the same time, a microphone picks up sound and also transformed into an electrical audio signal. Both combined signals are sent to a satellite, and this in turn sends them to a receiver that picks up the signal through an antenna, a satellite or cable. The TV receives signals. There, the leading audio signal to an amplifier and a speaker.
OLD TVThe television appearance quickly shifted radio room to the bedroom, bathroom or kitchen. The team is pictured on the left, presenting for Decca in the 19 th National Exhibition of Radio and Television in London in 1952, combining radio with television in one cabinet, the screen size allowed large groups to attend program in order successful, as the popular Show Lucille Ball, which is an image on the right.
COLOR TELEVISIONThe color TV was launched in the United States and other countries in the 1950's. In Mexico, the first color broadcasts were made in 1967 and in the next decade in Spain. Over 90% of households in developed countries now have color TV.
TELEVISION IN SPACESpace TV Television cameras aboard the spacecraft transmitted to Earth U.S. space information hitherto inaccessible. Mariner spacecraft, launched by the United States between 1965 and 1972, sent thousands of images of Mars. The Ranger and Surveyor series broadcast thousands of photographs of the lunar surface for analysis and scientific development before the manned lunar landing (July 1969), while millions of people around the world could watch the broadcast in color directly from the lunar surface .