Radio is a product using wireless radio technology. The advent of radio and radio functions has brought much practical utility for human life. Currently, there are no more people use radio as the replacement of other technological devices. However, radio still plays an important role for the historical information and entertainment of humankind. You certainly will never forget the songs are played on the radio, and you will not forget the feeling of excitement when detecting the frequency of a favorite radio channel!
Electromagnetism and Electromagnetic Wave Theory
In the course of research in the field of wireless signal transmission, a series of experiments have been conducted since the early 19th century to study the relationship between electricity and magnetism based on previous predictions. 1831, Michael Faraday made a series of experiments to prove the existence of electromagnetic induction. This relationship was he built a mathematical model of Faraday’s Law. Accordingly, the electromagnetic force can be spread out into the space around the wires. From 1861 to 1865, based on the study of Faraday and other scientists, James Clerk Maxwell developed a theory known as the theory of electromagnetic waves. The theory has been published in the scientific journal Royal, and title of a theory was “dynamism of the electric field.” He was the one who united the important concepts of modern physics: electric, magnetic and light by four famous Maxwell’s equations. Although he is not the inventor of the radio, this theory has laid a solid foundation for the birth of radio waves as well as the radio today.
The First Radio Signal of Human History
Guglielmo Marconi- an Italian inventor who demonstrated the feasibility of radio communication in space. He had successfully sent and received first radio signals in 1895. And in the early 20th century, Marconi began transmitting ideas across the Atlantic. In 1901 he transmitted the first wireless signals across the ocean from Poldhu, Cornwall (southwest region of the United Kingdom) to the hill Signal Hill (owned by Canada). 1909, Marconi and Karl Braun joined Ferdinand received the Nobel Prize in physics. In addition to Marconi’s case, two contemporaries as Nikola Tesla and Nathan Stufflefield also received a patent for radio transmitters in the US.
The Development Phase of The Radio System
The information was transmitted by radio waves was similar as long-short signals (Morse code). In the first moment, the signal generator was called “spark-gap machines.” It was developed to guide the ships at dock, or to keep in touch between the boats together. A method for wireless signal transmission by radio waves has proved its effectiveness in the rescue when natural disasters occur. Devices for wireless signal transmission systems have been installed on some ships. 1912, telegraph communication services using radio waves the first trans-Pacific had been established between San Francisco and Hawaii.
Communication services using radio waves have slow growth. Because the generation of the first wave generator was made with high costs. Currents in electrical systems and flow between electrodes release have not been stable. However, then the high-frequency generator of Alexanderson and Triode vacuum tubes of De Forest have been largely overcome these primary shortcomings. Lee De Forest invented the telegraph through space technology use Triode amplifier and three pole lamp (Audion). De Forest’s invention is the amplifier and modulation or AM radio. They allowed signals to be transmitted to different stations than conventional methods spark-gap-ray information previously only allows communication between two points. This was the premise of communication technology with a modern radio that De Forest was the biological father.
The First Radio Program Was Born
In 1915, the first voice was be transmitted across the continent by marine radio NAA. The sound has come from New York to San Francisco, crossing the Atlantic Ocean to the Eiffel Tower in Paris. November 2, 1920, radio station KDKA – Pittsburgh had broadcast the election results Harding-Cox and began a daily radio program. In 1965, an antenna system of the first FM broadcast around the world was built on the Empire State Building in New York.
In 1927, radio communication system connecting North America and Europe had been established, and three years later it was able to connect more South America. Until 1935, the first call is made around the world, using a combination of the radio system wired and wireless.
The Introduction of FM and The Appearance of The Radio
In 1933, Edwin Howard Armstrong invented the radio wave inverter (also known as FM radio). FM has the advantage of limiting the interference caused by other electronic devices, and the magnetic field of the Earth. By 1936, all telephone communications of US transatlantic was transmitted to England. Up to that time, communication networks both wired and wireless can connect the US with nearly 187 other points overseas.
1965, an antenna system of the first FM broadcast around the world are built on the Empire State Building in New York. This system has allowed the private FM radio stations can broadcast from one source to multiple different receivers. This is also the radio model is widely used around the world to this day.
Listening To The Music In The Radio
You can listen to music on a variety of media such as television, computers, laptops and even on the phone. In particular, many people often use the radio to listen to music. Radio is a very useful means for you to hear to music, foreign language learning through a foreign language news channel. Also, you can interact, make friends, give gifts to friends via the radio program. A good radio will let you study, entertainment and exchanges friends everywhere.