Some people say that the telephone is a song that has been sung for 100 years. It is still full of sound, echoing all over the world. 100 years, although the basic function of telephone as a human voice transmission mode has not changed much, with the progress of technology, it has experienced the development process of "magnetism-* * * electricity-automation".
1753, 17 In February, a letter signed by C.M. was published in The Scotsman magazine. In this letter, the author put forward a bold idea to communicate with electricity. He suggested that a set of metal wires be extended from one place to another, and each metal wire corresponds to a letter. When sending a message at one end, the wire is connected to the static motor according to the message content, so that it passes through the current in turn. The current passes through the small ball on the metal wire and sucks up the small pieces of paper with different letters or numbers hanging on it, thus playing the role of transmitting information over a long distance.
One of the earliest telegraph equipment.
1On July 9th, 839, a 5-pointer telegraph co-produced by retired British military officer William Fo Sengir Cook and natural philosophy professor Wheatstone of London Institute of Advanced Studies began to be used on the railway line between Paddington Station in London and West Dryden, with a distance of 2 1km. After that, they continued to improve the telegraph until the early 20th century, when it was used on British railways.
Five-pin telegram
Five-pin telegraph works: two hands refer to the same letter being transmitted.
1844 On May 24th, Morse sent the first telegram in human history from Washington to Baltimore. In the packed Capitol, Morse manipulated the telegraph machine he had worked hard for more than ten years with trembling hands, and said, "What a miracle God has created!" In a word.
Morse sent the first telegraph equipment.
1August 28, 850, British John and Jacob? Jacob Brett and his brother laid the first submarine cable in the Dover Strait between Britain and France on the high seas between Cape Grice-Nez in France and Cape Souther-Rand in England, but it was interrupted after only a few telegrams, because a fisherman hooked a cable with a trawl and happily cut off the next section.
1858 On August 5th, the first submarine cable crossed the Atlantic Ocean. The Atlantic submarine cable was laid from Valentia on the west coast of Ireland on August 7th. 1857. 17 On August 7th, the submarine cable broke at a depth of 12000 feet. 1On the night of July 28th, 858, two cable laying ships met again in the middle of the Atlantic Ocean. After the cables are spliced, the cable laying ship lays the cables in the opposite direction. On August 5, 3240 km of cable was laid. At 2: 45 am, the first submarine cable crossed the Atlantic Ocean. On August 12, submarine cables and telegrams were broadcast between the United States and Britain. On September 3rd 1, the cable insulation was damaged due to the operator's mistake.
1858 cable laying ship
On May 1865 and 17, representatives from 20 European countries, including France, Germany, Russia, Italy and Austria, signed the International Telegraph Convention in Paris, and the International Telegraph Union (ITU) was also proclaimed. 1932, representatives of more than 70 countries held a meeting in Madrid, Spain, and decided to officially change its name from 1934 1 to "International Telecommunication Union". 1969 may 17, the 24th executive board of the international telecommunication union formally passed a resolution, and decided to designate may 17, the founding day of the international telecommunication union, as the "world telecommunication day", and requested all member states to start from1969, and every may 17. 1973, the international telecommunication union once again passed a resolution, demanding that member States continue to carry out various commemorative activities in various ways. In order to make the commemoration more systematic, there is a theme for World Telecommunication Day every year.
The first international telegraph conference was held in 1857.
1On July 28th, 866, the second submarine cable laid by the British "Oriental Great Ship" transmitted the first telegram, and since then, the submarine cable has become a conventional communication tool.
Oriental great ship
1871on may 23rd, the Danish Dabei telegraph company can send a telegram in China.
1On June 2nd, 875, the telephone was invented by American Bell Arikan Del Graham. Today, there is still a bronze medal at the gate of Court Road 109 in Boston, USA, which reads: 1875 Telephone was born here on June 2nd.
1876 On February 4th, Bell applied for a patent for the famous device-telephone that he and Watson have been studying. On the same day, another inventor, Gray (1835- 190 1), also submitted a patent application for similar equipment to the US Patent Office, but Bibel lost the right to invent the telephone just because he was a few hours late.
Bell obtained a patent certificate for telephone.
1March, 876 10, Bell accidentally spilled sulfuric acid on his leg while doing the experiment. He cried out in pain, "Mr Watson, come and help me!" " Unexpectedly, this sentence reached the ears of his assistant Watson, who works in another room, through the telephone in the experiment. This very common sentence, however, became the first voice transmitted by telephone and went down in history.
Bell's experimental sketch
1April 4, 877 Charles, USA? Williams set up the first private telephone line to connect his factory with his private residence in Somerville.
1877 On April 27th, Edison applied for a patent, which is an improved telephone microphone. Two weeks before this, someone applied for a patent for the invention of telephone microphone. But Edison's great achievement made people ignore this man named emile berliner. The significance of telephone microphone is to make the telephone practical.
1877 may 17, Edwin Homais of Boston burglar alarm shop used the telephone switchboard system for the first time, and five branch lines were connected to five offices equipped with burglar alarm bells.
On July 9th, 1877, Bell Telephone Company was established.
1878 65438+1On October 28th, the first local telephone exchange was opened in Newhorn, Connecticut, USA, with only 20 users at that time.
On February 1878, the world's first telephone book was published in New Haven, Connecticut, USA.
The world's first telephone book
1On March 25th, 878, Bell, the inventor of the telephone, predicted, "It is conceivable to bury the telephone line underground or hang it in the air and connect it to private houses, villages, ships and factories. You can also set up a CLP telephone office to connect Yunnan and Guizhou through trunk cables. In this way, any two places in the city can talk directly as needed. This scheme, even if it is difficult to realize at present, I am sure it will be the development direction for the public to adopt telephone communication. I also believe that in the near future, telephone lines can also be connected to the headquarters of telephone companies in various countries, and even everyone in all parts of the country can directly talk to people in other places. "
1879, Edison made a carbon microphone by electromagnetic effect, which significantly improved the effect of sending information. The principle and device of Edison's carbon microphone have been used to this day.
1879, the phone number at the bottom appears. It was put forward by a physician inspired by the measles epidemic in Massachusetts, because once the operator gets sick, the telephone in the whole city will not be paralyzed.
188 1 year, British electrical technician Pi Xiaopu set up a pair of open-air telephones along the street in Shanghai Shiliupu, paying 36 francs for one call. This is China's first telephone.
188 1 year, Rome, Italy, Paris, France and Berlin, Germany successively opened the first telephone network.
1882, and the telephone line is twisted pair. This is the result of the paper on overhead line interference published by British professor Hughes in 1879.
On March 2 1887 and 2 1 day, German physicist Hertz found in his experiments that the energy of electric spark can travel far across space. This is the first time in human history that the existence of electromagnetic waves has been confirmed. However, Hertz categorically denied the possibility of using electromagnetic waves for communication. He thinks that if we want to communicate with electromagnetic waves, we need a giant mirror the size of the European continent.
On May 1889, William Grader invented the pay phone in Hartford, Connecticut. Soon, a telephone booth appeared in the street.
1892165438+1On October 3rd, the "stepped automatic telephone exchange" made of connectors invented by Strowger was installed and used in laporte, Indiana, USA. This is the first automatic exchange.
Strowger switch schematic diagram
1on may 7th, 895, popov, 36, read a paper on "the relationship between metal fragments and electric oscillation" at the physics branch of the Russian society of physical chemistry in Petersburg, and publicly showed the radio receiver he invented. When his assistant Rybkin turned on the spark generator at the other end of the hall, popov's radio receiver rang; Disconnect the radio generator and the bell will stop immediately. Decades later, in order to commemorate popov's epoch-making pioneering work on this day, the then Soviet government designated May 7th as "Radio Invention Day".
Radio receiver for popov experiment
1896 On March 24th, popov and Rybkin performed a performance of transmitting Morse code by radio at the annual meeting of Russian Physical Chemistry Association. They manipulated their radio transceiver and sent the word "Heinoich Hertz" to show their respect for the pioneer of electromagnetic waves. Although the communication distance at that time was only 250 meters, it was the earliest telegraph with clear contents transmitted by radio in the world.
1May, 89718th, Marconi succeeded in radio communication across the Bristol Strait, and the communication distance reached14km.
1899165438+1On October 22nd, the first radio communication company in America was founded by the New Jersey Association: Marconi Radio and Telegraph Company of America.
1899 On March 28th, Italian physicist G Marconi set up a radio station in Cape South Flanders, England, to communicate with Vermeer in France. The distance between the two places is 3 1 mile, which realizes the radio communication between Britain and continental Europe. Compared with popov, who was snubbed in Russia at the same time, Marconi was much luckier, and he got the full support of the British Post Office. 1June 2, 896 obtained the patent of wireless telegraph; 1in June, 900, he built a high-power transmitting station in Purdue, England, using 10 kW acoustic spark telegraph transmitter; 19011February, Marconi successfully received a telegram from Purdue Radio through an antenna towed by a kite in St. John's Port, Newfoundland, Canada. Marconi's success caused a great sensation all over the world and pushed radio communication to a comprehensive and practical stage.
Marconi sent a copy of the first wireless telegram.
1907165438+1October 8 Edward? Belan performed a photo fax in public-sending pictures by electricity. It is generally believed to be Edward? Belan makes fax technology practical. Belan 1876 was born in France, and has shown extraordinary talent since childhood.
On February 23rd, 1920, the world's first wireless telephone news service was launched.
The first wireless telephone news service
On June 5th, 1920, Marconi held a "radio telephone" concert in England. The music of the concert spread all over Britain, as well as Paris, Italy and Greece, where radios can receive it. In the same year, the Soviet Union, Germany and the United States also conducted radio broadcasting for the first time.
1925 10 10 On February 2nd, the British inventor Baird finally made the world's first TV set with practical value on the basis of previous research.
On June 30th, 1948, Bell Laboratories showed the transistors used to replace vacuum tubes to the public.
transistor
1957 10 year 10.4, the former Soviet union launched the first artificial earth satellite, and the earth received the electric waves from the artificial satellite for the first time. It not only marks the beginning of the space age, but also means that an era of satellite communication is coming.
1 On August 2, 1960, the U.S. Department of Defense launched the balloon satellite "Echo1"with a diameter of 30 meters and an aluminum film on its surface into a circular orbit about 1600 kilometers above the ground for communication test. This is the world's first "passive communication satellite". Because there is no power supply on this satellite, it is called a "passive satellite". It can only reflect signals and be received by other places on the earth, thus realizing communication. However, due to its low efficiency, this method is of little practical value.
1962 In July, the National Aeronautics and Space Administration (NASA) launched the world's first active communication satellite Telstar I( 12, 13 February). The satellite is equipped with a radio transceiver and a power supply, which can receive, process and amplify the signal before launch, thus greatly improving the communication quality.
“Telstar 1”(Telstarⅰ)
In July 1962, 1 1, Telestar 1 successfully carried out the transatlantic television broadcasting and multi-channel telephone transmission test between Andover Station in Myanmar, USA, Gonxili Station in Britain and Plummer-Bodo Station in France.
Commemorative coins issued to commemorate the first broadcast to French television on July 1962+0 1.
1On July 26th, 963, NASA launched the "Syncom" communication satellite, which realized telephone, telegraph and fax communication between Africa, Europe and the United States. Because this satellite has an inclination of 30 degrees, and its orbit moves in a figure of eight relative to the ground, it is not really "synchronous", so it cannot be called a "geostationary satellite".
Space synchronous satellite
1On August 23rd, 963, President Kennedy quoted Morse's first public telegram message "What a miracle God has created" to end his conversation with the Nigerian Prime Minister. This is the first telephone call through the "Syncom" communication satellite, and the sound has spread over 72,000 kilometers.
1964 on August19, the United States launched the "Syncom III" satellite. This is the world's first geostationary orbit communication satellite. 1958 18 February 18, the United States launched its first communication satellite, but it only worked for 13 days due to technical reasons. Since then, satellite communication has entered the experimental stage. From 1963 to 1964, the United States launched three experimental geostationary orbit satellites, and only the third satellite, Synchronization 3, was completely successful.
1964 On August 20th, the International Telecommunications Satellite Consortium headed by American Telecommunications Satellite Co., Ltd. was established, and the following year it was renamed the International Telecommunications Satellite Organization, the famous INTELSAT. Headquartered in Washington, DC, the organization aims to propose and develop a global communication satellite system, which can be used equally by all countries in the world to improve their telecommunications services. The performance standards of satellite communication system and standard earth station have been established, and satellite communication service has officially become an international commercial service.
1On April 6th, 965, INTERSAT launched a semi-experimental and semi-practical stationary communication satellite, Earlybird, also known as Intelsat 1. As the first practical commercial communication satellite in the world, it provides communication between North America and Europe. "Early Bird" marks the beginning of synchronous satellite communication era from experimental stage to practical stage.
The first practical commercial communication satellite-"Early Bird"
1 February 9991day, GMDSS system was put into full use in all shipping countries in the world. Unlike SOS, which was widely used before, GMDSS is a new type of ship-shore communication system-"Global Maritime Distress and Safety System". It consists of satellite communication system and terrestrial radio communication system. The satellite system consists of two parts: Inmarsat subsystem and very low orbit search and rescue satellite subsystem. GDMSS is an advanced system based on advanced satellite communication technology, digital technology and computer technology. When a ship is in distress, it can not only send rescue information to a wider range more quickly and reliably, but also replace the previous manual alarm methods with automatic and semi-automatic methods.