Broadcasting simply means sending out or receiving messages. The two most important media of broadcasting are the radio and television. Broadcasting is simply based on the way people hear or see. Radio makes use of the air vibrations called sound waves to agitate our sensitive ears. Television on the other hand, made possible its broadcasting through the use of electro-magnetic energy called light rays to which our eyes are so sensitive.
Radio comes from Latin word radius , which means ray , or a straight line from a central point to any point in the circumference of a circle. In French, radio is called tsf which literally stands for telephonie sans fil or in English, “telephone without wires.”
Television, on the other hand, comes from two words combined together. The Greek word tele means “from a great distance,” while visio is a Latin verb which means “to see.” That’s is why, that event on July,1969 was seen because television means “seeing from a great distance.”
The history of radio
Do you know that the first individual who had brought the idea of radio was laughed at? That man was James Clerk Maxwell, a pupil of another great inventor in the wonderful world of electronics and communications, Michael Faraday. Maxwell, theorized about the laws governing space energies, which we know now as radio waves; that these energies could travel as fast as light waves and that they could also be bent, focused, absorbed, and reflected. He was able to make an accurate estimation of that speed. He also remarked of the possibility of these waves to be produced and controlled by man.
Edward Hughes built his first radio receiver and actually heard radio waves in the center of London in 1879, but, unfortunately, neither he nor Maxwell were believed even by the Royal Society of London where Michael Faraday was a Fellow. It was not until 1888 that a German professor, Heinrich Hertz, carried out practical experiments that proved Maxwell’s theory correct.
Hertz’s experiment was very simple. He just wanted to find out if it was possible for a wire, used to represent as aerials to transmit electrical charges across a gap. He placed two jars in opposite corners of his laboratory and he found out that the spark jumped from one jar to the other. Those were the first radio waves which were called as Hertzian waves . Because of that experiment, Maxwell had been proven to be correct.
The history of television
There had been numerous physicists, professors, and inventors involved in working out experiments and other scientific discoveries in sending out radio waves containing not only sounds but also images.
Paul Nipkow, a German engineer, invented a way of transmitting pictures. His apparatus consisted of a disc, known later as the Nipkow disc, where spiral of holes were cut. As the disc revolves, each hole yields spiraling slice-like scenes for transmission. This operation was simply called as scanning. By exposing the scanned images into a screen made of selenium, the first television transmission was achieved.
Since selenium’s response to light was slower for the fast-moving discs, another inventor, Weiller, replaced the selenium with rubidium because of its faster response to light. Weiller also used mirror drum instead of revolving discs and a Cathode Ray Tube (CRT) which serves as the transmitter as well as the receiver. This invention of Weiller further gained prominence when an Austrian physicist, Professor Braun, used a mica screen coated with phosphorous. The shadow that appeared was dramatically noticeable.
The first radio transmission of a moving picture of a human face was spectacularly consummated by John Logie Baird in 1926. Prior to that, in 1923, he experimented to broadcast a picture of a ventriloquist dummy over a short period using the “old-fashioned” Nipkow scanning disc. Baird was the first man to broadcast television pictures for the British Broadcasting Corporation (BBC) in 1929 and 1930, and in 1931, he broadcasted pictures of Derby horse race. His broadcast was seen on an 8 inches x 10 inches screen, which, during that time was already considered a breakthrough unlike today.