It is expected that nearly all U.S. households have at least one radio. The invention of radio was dependent upon two previous discoveries: the electromagnet and telegraph. The electromagnet was discovered in 1825. This discovery has opened the doors to global communication! Five years later, Joseph Henry successfully transmitted an electric current through wire that was stretched over a mile and which caused an electromagnet to trigger the ringing of a bell. Thus, the electric telegraph was born. One of the most recognizable names associated with the telegraph is Samuel Morse who is most notable for the number of points (its short) and dashes (his support) that was used to transmit messages by a code letter (so called Morse code). Telegraph became the only means of rapid communication and long distance until 1877 and the invention of the telephone.
The batteries are interesting, they don t? Used by the general public, they are small, but powerful tools packaged produce energy used for many cameras, clocks, radios and other devices. What makes this production of energy possible? In the case of the phone and it s the design and use quick, batteries produced the essential source of energy for the electro-magnet.
Batteries have two ends of which is assigned a "+" or positive, and the other a "-" or negative. When the device is a battery operated light is on, electrons are produced by cells to move quickly on the negative side to positive side of the battery. Something was necessary to interrupt the flow of fast electrons or find batteries fully spent a short time. To do this, a wire is often inserted between the positive and negative terminals and a "force" such as radio, creating a small magnetic field in the wire. Electromagnetic waves that are present today, have the ability to transmit sound (speech, music, etc.) as well as visual images detected by sight in the air.
There are many scientists who must be mentioned as essential to the phone because it is known to most of us. Mahlon Loomis developed wireless telegraphy. Guglielmo Marconi, proved the possibility of radio communication. In 1985, Marconi sent and received radio signal. Using Morse code, he sent the first wireless signal that was transmitted across the English Channel and on time, he was able to receive the letter S Morse began in England and reached Newfoundland Newfoundland, which became the beginning of the transatlantic wireless telegraphy (1902).
Wireless signals acquired wide-range use as a means of communication for relief operations in case of accident or disaster at sea in 1899, the U.S. military began using the wireless communication that came from a lighthouse off Fire Island. The U.S. Navy has been about two years behind the army using wireless telegraphy.
In 1903, President Roosevelt (Theodore) and King Edward VII sent through this new technology and improvement. The well-known Robert Perry, using radio, conveyed the message that he had found "the hub".
The first AM radio entered the world of telecommunications in the 1900s, the Art This feature makes the use of airwaves a bit low as possible for communication. This was the moment when the term "radio" as we now know, for radios, began to be used.
It is estimated that in December 23, 1900, Professor Reginald Aubrey Fessenden was the first person to successfully transmit the human voice by radio waves. In 1915, the word was first sent to the United States from New York and sent to San Francisco. A little later, the transmission occurred through the Atlantic Ocean in Arlington, Virginia, in Paris at the Eiffel Tower.
It's really fascinating to all scientific and physical theories that led to the invention of radio. Marconi, Alexander Popov, Oliver Lodge, Fessenden and many others, have all made an important contribution to an invention that has made the world so different, no more likely to consider them. The radio era was born.
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Roberto Sedycias works as IT consultant for www.PoloMercantil.com.br