TelevisionTelevisionTelevision is the coolest entertainment in America today. According to one estimate, the average American spends 9 years watching T.V. in his/her life.
After the radio, scientists discovered ways to send pictures by radio waves, too. John Logie Baird created a mechanical system in 1926. A wheel with holes whirled around. Light went through each hole to create a scene in a split-second.
A light detector turned the patches of light into
electrical signs, and a radio transmitter sent these as radio waves.
The receiver was a second wheel working in the other way. Baird’s
system was used for a short while, but it had mechanical problems.
The electronic TV system that we use today was made by Viadimir Zworykin,
in the USA in the 1920s.
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