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LESSoN EIGHT
TEXT
Telecommunication via Satellite
At the beginning of the twentieth century, there were four powerful means of transmitting and receiving information over long distances: print, photography, telegraph, and telephone. By the middle of the century, both radio and television had become established means of transmitting sounds and/or pictures. In 1964, the olympic Games in Tokyo became the first program to be transmitted via satellite.
In order to transmit an event such as the olympics via satellite, television signals are first changed into radio waves, which are then sent from a station on earth to an orbiting satellite. The satellite receives the radio waves and sends them back to earth, where another station picks them up and changes them back into television signals. Because any form of sound or visual information can be changed into radio waves, satellites are capable of transmitting not only television broadcasts, but telephone calls and printed materials such as books and magazines.
The combination of satellites,(s) which transmit information, computers,(s) which store information, and television,(s) which displays information, will change every home into(o) an education and entertainment center. In theory, every person will have access to an unlimited amount of information.
Another important use of telecommunication satellites was demonstrated in 1974 when the Teacher in Sky satellite transmitted educational programs to classes in remote areas of the United States. In 1975, many people in India saw television for the first time as(when) they watched programs about agriculture and health.
The satellite also demonstrated how it could provide help to people living in isolated areas where transportation is difficult. For example, a health worker in an isolated area was able to transmit pictures of a patients wound to a doctor far away. He was then able to follow the doctors instructions on how to care for the patient.
The most common use of telecommunication satellites, however, has been for transmitting telephone calls.
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