The research on long-distance sound transmission in Europe began in17th century. Robert hooke, a famous British physicist and chemist, first put forward the suggestion of long-distance voice transmission. 1796, Hughes put forward the method of transmitting voice information through microphone relay, and called this communication method-telephone, which has continued to this day.
1832, American doctor Jackson told the passengers about the principle of electromagnet on a mail ship sailing in the Atlantic Ocean. Among the passengers, American painter Morse, 4 1 year-old, was deeply attracted. At that time, the French signal system could only send miles of information visually. Morse dreamed of using electric current to transmit electromagnetic signals and instantly send information thousands of miles away. Since then, Morse's life has undergone fundamental changes.
Morse's inspiration comes from the fact that the current flowing in the conductor will spark in generate when the conductor is suddenly cut off: if the current is cut off as a signal, the current is turned on without spark as another signal, and the current is turned on for a long time as a signal, these three signals can represent all letters and numbers together, and words can be transmitted to a distance through the current. 1837, Morse finally designed the famous Morse code, which used different combinations of "dot", "dash" and "interval" to represent letters, numbers, punctuation and symbols. 1844 On May 24th, Morse personally operated the telegraph in the meeting room of the Federal Supreme Court of the Capitol in Washington. With a series of "dot" and "dash" signals, Baltimore, 64 kilometers away, received the world's first telegram composed of "beep" and "click".
[Edit this paragraph] The invention of the telephone
The inventor of the telephone-antonio meucci.
It has been so many years. On page 75 of the third grade of History and Society, Science, Technology and Culture in19th Century mentioned: "American Bell invented the telephone, which fundamentally changed the way of human communication." As for the inventor of the telephone, due to the writing time, the textbook still adopts the traditional view that the invention right of the telephone belongs to Bell. However, the real inventor of the telephone is controversial in history, which involves three related figures: Bell, Gray and meucci. The information provided to the students below is not to subvert our textbooks, but to let everyone have a more comprehensive and detailed understanding of this issue through in-depth exploration.
For most people, whenever the invention of the telephone is mentioned, it will definitely be associated with Alexander Graham Bell. Bell has done a lot of research, explored the composition of voice and analyzed the vibration of voice on precision instruments. On the experimental instrument, the vibration on the diaphragm is transmitted to the glass sheet blackened with carbon, and the vibration can be "seen". Next, Bell began to think about the possibility of converting sound vibration into electronic vibration. So that sound can spread through the line. Over the years, Bell tried to invent several telegraph systems. Gradually, Bell came up with an idea to invent a machine that can transmit several messages at the same time through a single line. He envisioned several armatures to coordinate different frequencies. At the transmitting end, these armatures will cut off the current at a certain frequency and send a series of pulses at a specific frequency. At the receiving end, only the armature matching the pulse frequency can be activated. Bell accidentally discovered in the experiment that transmitting electromagnetic waves along the line can transmit sound signals. After several experiments, the sound can be transmitted stably through the line, but it is still unclear. Because of Bell's heavy teaching tasks, his research has not made progress for a long time. 1876, on the eve of Bell's 30th birthday, the idea of transmitting sound through wires was unexpectedly patented. Bell rekindled his enthusiasm for research. 1876 March 10, Bell's telephone call announced the arrival of a new era in human history.
However, Bell was not the only one who devoted himself to inventing the telephone. A man named Elisha Gray once filed a lawsuit with Bell over the telephone patent right. Gray and Bell filed the patent on the same day, but Bibel was a little late (only about 2 hours late) and finally lost the case.
Actually, regarding the invention of the telephone, we should also think of another unknown Italian, antonio meucci, who immigrated to the United States from 65438 to 0845. Meucci was obsessed with electrophysiology, and he accidentally discovered that radio waves can spread sound. From 1850 to 1862, meucci made several different forms of sound instruments, which are called "long-distance microphones". Unfortunately, meucci is too poor to protect his invention. At that time, applying for a patent required an application fee of $250, and the long-term research work had exhausted all his savings. Meucci's English level is not high, which makes him unable to know how to protect his invention. Then, fate gave meucci a greater blow. 1870, meucci was seriously ill and had to sell the telephone equipment he invented at a low price of only $6. In order to protect his invention, meucci tried to obtain a document called "Request for Protection of Invention Franchise". To this end, he needs to pay an annual fee of $65,438+00, and it needs to be updated once a year. Three years later, meucci was reduced to living on social welfare, unable to pay the handling fee, and his application was invalid.
1874, meucci sent several "long-distance microphones" to Western Union. I hope I can sell this invention to them. However, he didn't get the answer. When asked to return the original, he was told that these machines were gone! Two years later, Bell's invention came out and he signed a huge contract with Western Union Telegraph Company. Meucci filed a lawsuit and the Supreme Court agreed to hear the case. However, meucci died on 1889, and the lawsuit was dropped.
Until June 15, 2002, the US Congress passed a bill, which identified antonio meucci as the inventor of the telephone. Now there is a monument in Florence, the birthplace of meucci, which reads "Here lies the inventor of the telephone-antonio meucci".
At present, the recognized inventor of the telephone is Bell, who applied for the telephone patent right in the US Patent Office on February 1876. In fact, just two hours after he applied, a man named E Gray also applied for a telephone patent.
Before the two of them, many people in Europe were already doing ideas and research in this field. As early as 1854, the telephone principle was conceived by the Frenchman Bausal, and the idea was repeated by the German rice six years later. The principle is that two thin metal sheets are connected by wires. When one side makes a sound, the metal plate vibrates and becomes electricity, and the electricity is transmitted to the other side. But this is just an idea. The problem is the structure of microphone and receiver, and how to convert the mechanical energy of sound into electrical energy and transmit it.
At first, Bell used electromagnetic switches to form on-off pulse signals, but this method obviously didn't work for such high-frequency sound waves. The final success came from an accidental discovery. 1June 2, 875, in an experiment, he connected a metal plate to an electromagnetic switch. Unexpectedly, in this state, the sound becomes a wonderful current. According to the analysis principle, the original metal sheet induces current in the connected electromagnetic switch coil due to sound vibration. Now it seems that this principle is known to all students who have studied junior high school physics, but it is undoubtedly a very important discovery for Bell at that time.
Gray's design principle is different from Bell's, which uses the resistance change of the liquid inside the microphone, while the receiver is exactly the same as Bell's. 1877, Edison obtained the invention patent of carbon particle microphone. At the same time, many people have made various improvements to the way the telephone works. The patent dispute is complicated, and it didn't come to an end until 1892. One of the reasons for this situation was that the largest Western Union telegraph company in the United States bought the patents of Gray and Edison at that time and confronted Bell's telephone company. Due to the long-term patent dispute, the two sides reached an agreement. Western Union Telegraph Company fully recognized Bell's patent right and never set foot in the telephone industry again. In exchange, it shared 20% of Bell's income in 17.
[Edit this paragraph] The development of telephone technology
In the decades after the invention of the telephone, a large number of patents were applied around the operation and technology of the telephone. Strowger's "automatic dialing system" reduces all kinds of problems caused by manual wiring, the application of dry battery reduces the size of telephone, and the application of loading coil reduces the signal loss of long-distance transmission. 1906, Li De invented the electronic test tube, and its amplification function led the direction of telephone service. Later, Bell Telephone Laboratory made an electronic triode based on this, and this research is of great significance. 1915 65438+1On October 25th, the first cross-regional telephone line was opened between new york and San Francisco. It uses 2500 tons of copper wire, 6.5438+0.3 million telephone poles and numerous load coils, and also uses three vacuum tube amplifiers along the way to strengthen the signal. On July 1948, scientists at Bell Laboratories invented the transistor. This is not only of great significance to the development of telephone, but also has great influence on all aspects of human life. In the following decades, a large number of new technologies appeared, such as the production of integrated circuits and the application of optical fibers, which played a very important role in the development of communication systems.
[Edit this paragraph] The mobile phone is in China.
After the Opium War, while western powers plundered land and wealth in China, they also brought modern postal services and telecommunications to China. 1900, the first local telephone in China came out in Nanjing. Shanghai and Nanjing telegraph offices opened local telephones. There was only 16 telephone. 1904 to 1905, Russian radio stations are set up in the area from Yantai to Niuzhuang in China. The ancient postal system and non-governmental communication institutions in China have been gradually replaced by advanced postal services and telecommunications.
During the Republic of China, China's post and telecommunications were still under the control of western powers. Coupled with years of war, communication facilities are often destroyed. During the War of Resistance against Japanese Aggression period, the Japanese imperialists reformed and expanded the telecommunication network system for the need of war and the purpose of trying to rule China for a long time. They took advantage of China's backward economy and technology and the corruption of the political system at that time to control the telecommunications industry in China from the aspects of technology, equipment, maintenance and management.
Before 1949, China's telecommunications system developed slowly. By 1949, the telephone penetration rate in China was only 0.05%, and there were only 260,000 telephone users.
After 1949, the central people's government quickly resumed and developed communications. The Beijing Telegraph Building, completed in 1958, became an important milestone in the development history of new China communication. Ten years of "Cultural Revolution", post and telecommunications suffered another blow, and business development stagnated. By 1978, the national telephone penetration rate was only 0.38%, which was lower than the world level of110. The total number of telephones owned by China15 population is less than 1% of the total number of telephones in the world, and there is less than one telephone for every 200 people, which is 75 years behind the United States! The automation rate of switches is low, most counties and rural areas still use "crank", and long-distance transmission mainly depends on open wire and analog microwave. Even in Beijing, 20% of long-distance calls can't be connected every day, and 15% of long-distance calls can't be connected until 1 hour. Visitors to the telegraph building must take lunch to the queue.
1978, the national telephone capacity was 3.59 million, with 2140,000 users, with a penetration rate of 0.38%.
After the reform and opening up, the backward communication network has become the bottleneck of economic development. Since the mid-1980s, the government of China has accelerated the construction of basic telecommunication facilities. By March 2003, there were 225.626 million fixed telephone users and 22 1.4938+0.0000 mobile telephone users.
At all times, many people are trying to transmit information faster and better. During the telecom development of 100 years, people have tried various communication methods: the original telegrams used expressions similar to "numbers" to convey information; So there appeared a telephone that used analog signals to transmit information; With the development of technology, the digital mode has been paid more attention to with its obvious advantages. The historical wheels of digital program-controlled switching, digital mobile phone and optical fiber digital transmission are still advancing.
[Edit this paragraph] One hundred years of telephone development history
Since the invention of the telephone, there have been great changes from the working principle to the shape design. Please follow us through the century-long road of telephone development. Some of these telephones are collected by antique telephone collectors all over the world.
1684, robert hooke, a famous British physicist and chemist, put forward the principle of visual communication for the first time in a speech of the Royal Society. He suggested that when communicating, the letters of the text to be transmitted and the coded symbols representing various meanings should be hung on a high wooden frame for the other party to see and receive. But this proposal has never been realized.
1753, 17 In February, the idea of current communication was first put forward in a magazine named Scotsman, and the article was signed by C.M.
1790, Lauder Chape, an outstanding French engineer, and his brothers successfully developed a practical communication system based on Hooke's visual communication principle, which can send information to all France.
1793, the Chape brothers in France set up a 230-kilometer-long support line between Paris and Lille to relay information. This is a communication system consisting of 16 signal towers. The signalman controls the different angles of the bracket through the rope and pulley at the bottom to express relevant information.
1794 15 In August, a visual communication method called "Yuanwang" was first used between Lille and Paris.
1796, an Englishman named Hughes proposed a method of transmitting sound by microphone relay, and named it telephone, which has been in use ever since.
1832, Russian diplomat Schilling made a telegram that used galvanometer pointer to deflect the received information.
1835, American Morse invented the telegraph which used electromagnetic principle to transmit telegrams.
1in June, 837, an Englishman, Cook, obtained the first patent for the invention of the telegraph, and his telegraph machine was used on the railway for the first time.
From 1837 to 1838, Morse invented Morse code to encode numbers and letters by "turning on" and "turning off" current.
1843, Morse built a telegraph line from Washington to Baltimore, with a total length of 64.4 kilometers.
1844 On May 24th, Morse sent the first telegram in human history to Baltimore at the Capitol: "What a miracle God has created!" .
1850 On August 28th, the first submarine cable was built by John and Jacob. The Brett brothers laid cables on the high seas between Cape Grace-Naiz in France and Cape Richland in England, but they were interrupted only by sending a few telegrams. It turned out that a fisherman hooked a rope with a trawl and cut off a piece to brag about this rare "seaweed" specimen, and was surprised to say that it was full of gold.
1March, 876 10, the British Bell invented the telephone. "Mr Watson, come and help me" became the first voice on the phone. At that time, Bell spilled acid from the microphone on his leg.
1878, Handheld Phone: This phone was made by Werner Siemens in Germany on 1878. Its receiver and microphone are the same, and they are used alternately when listening and speaking.
1879, box-type mobile phone: This mobile phone is equipped with a magnetic generator made of mahogany, a viaduct manufacturing company, and a cylindrical receiver.
1879, a telegraph line was set up between Tianjin and Dagu Beitangbao.
1880, Bell Telephone: This is the first telephone used in Europe. It replaces the telegraph and is more advanced than the magnetophone with handle.
188 1, 1882, wall-mounted telephone of magnetic generator: the telephone on the left is American Bell model, 188 1 made, and Bell telephone in Copenhagen is used internationally. Made by L.M.Ericsson. This mobile phone was very popular at the end of last century.
1882 February 2 1 day, Gaodan Gaobei Telegraph Company set up a telephone exchange on the Bund in Shanghai.
1885, "Eiffel Tower" magneto phone: This phone was made by L.M. Ericsson in 1885. At that time, this was the first telephone on the desktop. The microphone is installed on the rotating arm, and the crank is used to connect the switch.
1885, 1902, wall-mounted telephone of magneto: 1885 Ferdinand e stensen made in Copenhagen, which is the earliest telephone made in Denmark. This model is made by Emile Deleuse Telephone Company of Hawthorne.
1885, wooden desk phone: manufacturer and origin unknown.
1892, electric folding counter phone: this kind of phone is mostly used in homes, hotels and telephone booths.
1892, "Eiffel Tower" telephone with receiver: this is a real classic telephone, 1892, made by L.M. Ericsson. This mobile phone has spread all over the world and produced nearly one million sets.
1893, "Coffee pot mobile phone": This mobile phone has only a few samples in Denmark, which is the most attractive and collectible for collectors.
1895, Russian popov and Italian Marconi invented the wireless telegraph respectively.
On May 6th, 2008, Marconi successfully conducted radio communication in Bristol Strait.
1899, digital mechanical on-hook: There are two types of digital mechanical on-hook: on-hook and desk phone.
1900, upright desk phone: This round-bellied desk phone is plated with bronze nickel. There is a strong bakelite under the hanging rod. It also has a peripheral phone to show off.
1900, upright conical desktop mobile phone: This mobile phone has the nickname of "oil pan" because of its shape.
1900, 20-line split phone: This is the so-called 20-line split phone. It can only be used for the internal telephone of Swedish company L. M. Ericsson.
1900, the first local telephone in China came out in Nanjing. Shanghai and Nanjing telegraph offices opened local telephones. There was only 16 telephone.
190 1 year, desk phone with magnetic generator: this model was made by Ferdinand e stensens Telefonfabrik in Copenhagen in 190 1 year. Pay attention to its receiver and hang it on the hook alone. It may be because the quality of telephone access was not high at that time, and sometimes two ears were needed to listen.
190 1 year, Marconi realized radio communication across the Atlantic.
1902, Kellogg corner desk phone: This corner desk phone is mostly used in homes, offices and telephone booths. It is made by American hardwood telephone company. I bought it from farmers in a small town in California.
1902, public battery wall telephone: This kind of telephone does not need to turn the handle, pick up the receiver and talk directly to the operator. It was bought from an antique shop in San Francisco.
1903, the wireless phone test was successful.
1904, "Spider" civil band telephone: L.M. Ericsson's first civil band telephone.
1904, magnetic generator * * * line telephone: this kind of telephone is produced by L.M.Ericssom company, and the telephone number is 1904. This phone can be shared by four users.
1904 to 1905, Russian radio stations are set up in the area from Yantai to Niuzhuang in China.
1905, tree-shaped desk phone in Chicago: This desk phone is called "paunchy", so it is named because the middle part of its handle is raised.
1905, porch intercom: This is the 32-door porch intercom of Connecticut Telecom.
1905, 1 1 digital dial desk phone: 1 1 digital dial mode is adopted.
108, French inventor Edward Belin showed his research results-photo fax in the building of the French Photography Association.
1907, "german mode" radio band phone: made by E.Zwuetysch &: Co in Germany 1907, the appearance of this phone can solve the problem of long call waiting time to some extent.
1907, magneto phone: This phone 1907 is made by L.M.Ericsson. It is worth noting that the receiver should be hung on a separate hook when answering the phone. This was the unified standard of telephone manufacturers at that time.
1908, CH-08 loudspeaker: KTAS introduced.
19 10, VoIP: This is a vertical desktop VoIP produced by S.H. Couch Company, which is used for communication between offices.
19 12, office organizer: This phone can have 17 extensions at the same time through the host, each extension can be dialed out, and the extensions can also be connected to each other.
19 12, CH-08 wall phone: this phone was made in 19 12. The Danes made it in Copenhagen and can send and receive telegrams automatically.
19 12, magnetogenerator telephone: telegraph and fax telephones made by L.M. Ericsson are often used in remote areas or small islands.
19 14, Magnavox anti-noise desktop mobile phone: The unique design of this mobile phone is that when talking into the microphone, the sound passes through the small hole on the top of the mobile phone, which makes the vibrating plate in the mobile phone vibrate. Noise will be eliminated when it enters the microphone. Its dual rotating headphones help prevent useless noise.
19 14, Magnavox anti-noise desk phone B 1: It also has the function of eliminating noise.
19 14, magneto phone: 19 14, made in hovens, can be used for telegrams and faxes.
19 15, Veau desktop phone: the information is unknown.
19 15. Homemade wall phone: This phone was found in an abandoned farm in East Oregon. There are nearly 20 abandoned farms in the local area, with traces of telephones hanging on the walls.
19 19, Pahlm and Behlander invented the "crossbar connector". Ten years later, 1929, the world's first large-scale vertical and horizontal telephone exchange was built in Sonzwar, Sweden.
In July, Chunghwa Post 1920 opened postal telegraph service.
1920, wall phone with magnetic generator: This phone was made in 1904 and updated in 1920, and it is equipped with a rotating red button, which can switch between receiving and listening.
1927, D-08 semi-automatic telephone: the first dial-up telephone, which will replace the manual call system of the exchange. The dialer was installed in 1927 and actually used in 1978.
1927, AC power generation ringing telephone: produced by Kristian Kirks Telefonfabrikker Company in Hohenson, Denmark, and still in use in 1970s.
1929, automatic wall-hanging telephone: the information is unknown.
1929, the world's first large-scale vertical and horizontal telephone exchange was built in Sonzwar, Sweden.
1930, D-30 semi-automatic gold-plated telephone: this telephone was made by Danish enterprises in 1930, and its feature is gold-plated surface. At that time, most telephones were dark, and this telephone had a dialing device.
1930, FL-30 automatic telephone: made in Denmark in 1930s, dialing letters. Similar mobile phones have been used for about 48 years.
1935, automatic telephone: This kind of telephone is used to communicate with telecom exchanges in remote areas, and its design was influenced by the American telephone industry in the 1930s.
1937, British Reeves proposed a method of transmitting voice information through all combinations of pulses (pulse code modulation).
1943, CB-43 telephone; This mobile phone is made by Kristian Kirks Telefonfabrikker in Denmark, and there are two kinds of ringtones designed inside to distinguish the incoming calls from those outside the city.
1945 10 month, English A? c？ Clark put forward the idea of geostationary satellite communication.
1946, eckert and mochiri built the world's first electronic computer.
1947, Bell Laboratories put forward the concept of cellular communication, which divided the service area of mobile phones into several cells, and each cell was equipped with a base station to form a cellular mobile communication system.
1950 65438+February, the international trunk line project of China Northeast Long-distance Open Line was completed, and the Beijing-Moscow cable carrier circuit was opened.
195 1 year, F-5 1 automatic dial-up telephone; This telephone was made by Kristian Kirks Telefonfabrikker after World War II.
1952, F-52 automatic dialing telephone: 1952, which is different from the previous black bakelite material. It is made of ivory and later plastic materials.
1In July, 954, the US Navy made use of the reflection of radio waves on the surface of the moon to conduct a telephone transmission test between the two places on the earth. At 1956, communication service was established between Washington and Hawaii.
1956, a telephone cable was laid under the Atlantic Ocean between Britain and Canada, making long-distance telephone communication between continents a reality.
1956, "Ericofon" automatic dialing telephone; This mobile phone is designed and manufactured by L.M. Ericsson of Sweden and named Ericofon. It is made of new material, which is much lighter than the receiver of traditional telephone.
1957, 10 year 10. On October 4th, the former Soviet Union successfully launched the first artificial satellite "1 satellite".
1958 In August, the first domestic 12 carrier telephone equipment was successfully developed in Shanghai Post and Telecommunications Equipment Factory.
1960 65438+ 10, the first set of 65438+ 10,000-door automatic telephone exchange in China was put into use in Shanghai Wusong telephone office.
1960, American physicist Mayman irradiated artificial gem with powerful ordinary light, and produced a laser with a light intensity of 0/00000 times that of the sun.
1962, the United States successfully developed a pulse code modulation device for telephone multiplex communication.
1965, the first program-controlled telephone exchange controlled by computer came out in America, marking the beginning of a new telephone era.
1966, Gao Kun, a British Chinese, put forward the idea of long-distance laser communication with glass fiber.
1968, F-68 automatic dialing telephone: this kind of telephone was the most common telephone in the 1970s. It was originally designed in 1960s and widely produced in Denmark.
1969, Beijing Long-distance Telecommunication Bureau successfully installed the first fully automatic long-distance telephone equipment in China.
1969, the Advanced Research Projects Agency (ARPA) of the US Department of Defense put forward a plan to develop ARPA network, which was completed and put into operation in 1969, marking the development of computer communication has entered a new era.
1970, the world's first program-controlled PBX was opened in Paris, marking the comprehensive application of digital telephone and the arrival of a new era of digital communication.
1970, F-68 push-button telephone: the first push-button telephone used in Denmark. This mobile phone uses numeric keys instead of the original dialing method.
In 1972, CCITT first proposed the concept of-—ISDN.
1974, the Sino-Japanese submarine cable started construction, which was the first international submarine cable that China participated in.
1975, the crossbar automatic telephone exchange equipment developed and designed by our country passed the national appraisal and began mass production.
1976,76e/dk80 push-button dialing telephone: originally produced by Jutland Telephone Company, the telephone number is 1972.
1976 in March, China's first large-capacity transmission system-1800 coaxial cable carrier system was completed and put into operation in Beijing, Shanghai and Hangzhou, with a total length of 1700 km.
1978, the national telephone capacity was 3.59 million, with 2140,000 users, with a penetration rate of 0.43%.
1979, F-79 key dial toll phone: this phone is between ordinary phone and public phone. Mainly used in service places, hotels and other similar places, you can make phone calls to prevent theft.
1980, DA-80 push-button dial phone: the design of this phone marks that the electronics theory has really entered the telephone industry.
1982, GSM was established in Europe, with the task of formulating roaming standards for pan-European mobile communication.
1982, portable telegraph telephone: this kind of telephone was made by Ericsson wireless system company, and it could only be used in Denmark, Finland, Norway and Sweden at that time. Its appearance has opened up a new world for the future GSM mobile phone system.
1982, the first batch of coin-operated public telephones in China appeared in busy streets such as East and West Chang 'an Avenue, with a total of ***22 coin-operated public telephone booths.
198212February, the first 10,000-door program-controlled local telephone exchange system imported from China was put into operation in Fuzhou Telecommunications Bureau, and the first program-controlled telephone exchange office imported from China was built.
1983, the AMPS cellular system was opened in Chicago, USA.
1983, Danish 2 push-button telephone: Danish 2 is made by 1983, which is the embodiment of the most advanced technology in the 1980s. It has many functions, such as telephone number memory function, redial function, monitoring function and 24 kinds of ringtones.