COMMUNICATION TECHNOLOGY
MAR 17, 2022
Let’s Tune In To The History Of Radio
Let’s tune in to the history of radio, a very useful invention for human technology and civilization in modern day.
Radio is a technology used to transmit signals by means of modulation and electromagnetic radiation (electromagnetic waves). Electromagnetic waves are waves that do not require a medium for propagation and can also propagate through the vacuum of space, because these waves do not require a carrier medium (such as air molecules).
Electromagnetic energy propagates in waves through several characters such as wavelength, amplitude, frequency and speed. Information that will be sent via electromagnetic waves is modulated by the wave components, namely amplitude, frequency, phase or pulse width.
But if the electromagnetic wave exposure exceeds the safe limit, it can also affect human health. Heavy exposure to electromagnetic waves that are too frequent can cause a decrease in the quality of human life such as headaches, insomnia, to increased anxiety.
The theoretical basis for the propagation of electromagnetic waves was first described in 1873 by James Clerk Maxwell (1831 – 1879), a Scottish scientist.
The birth of radio started in 1895 when Guglielmo Marconi managed to create a tool to realize his ideas. He demonstrated an ingenious device that became known as the “radio” in England in 1896. Marconi rushed to set up the company and the first “Marconi” was sent in 1898. The following year he was able to send news wirelessly across the English Channel. He later patented for his invention.
Marconi was born in 1874 in Bologna, Italy from a wealthy family. He received private education from a teacher. In 1894, when he was twenty, Marconi read about the experiments carried out by Heinrich Rudolf Hertz (1857 – 1894) conducted a few years earlier. Hertz was a German physicist who discovered the wireless transmission of electrical energy from two points.
Marconi patented his invention of a wireless telegraph using two circuits. The tool he discovered was the beginning of the use of technology to create radios. At that time this signal could only be sent at close range. However, this is what started the development of radio technology.
The first time a radio station aired their program was on November 2, 1920 when the radio station KDKA began broadcasting for the first time and was listed as the world’s first commercial radio station. The radio broadcast aired in the afternoon.
There are several ways to transmit radio waves through the air, one of them uses Short Waves (SW). Its working mechanism is to throw sound waves with a certain angle to the celestial ceiling. The sound in the form of the wave is then reflected at the same angle to the surface of the Earth.
The other form of radio waves are AM and FM. AM stands for Amplitude Modulation, while FM stands for Frequency Modulation. As the name suggests, this is what will be changed when sending a voice signal. In AM mode, the amplitude or the high and low of the sound signal wave is changed while FM is generally used on VHF radio frequencies to broadcast high quality music and conversations.
Audio from normal TV broadcasts is also broadcast using FM. In addition, FM is also used to send signals into space. This is because FM radio produces better sound quality and its radio waves are more resistant to inclement weather than AM radio.
FM radio waves have the following characteristics: the modulation produces a change in frequency, constant amplitude, variable frequency, FM waves cannot be reflected by the ionosphere layer, so the signal range is not too wide, more resistant to interference because the signal range is not wide.
Historically, the first radio broadcast in Indonesia (Nederlands Indie – Dutch East Indies), was Bataviase Radio Vereniging (BRV) in Batavia, which was officially established on June 16, 1925.
The history of radio station in Indonesia began when Radio Republik Indonesia (RRI) was officially established on September 11, 1945. Since then, September 11th is always celebrated as National Radio Day as well as the birthday of RRI which was founded almost a month after the broadcast of Hoso Kyoku, a Japanese radio station, that was stopped on August 19, 1945.
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