1. Amber Amber and Magnet Among the seven Christians in Greece is a philosopher named Thales. Before and about 600 BC, Thales saw that the Greeks had been thinking about the causes of the phenomenon of the time when the Greeks used frictional amber to attract feathers and used magnetite ore to attract iron. It is said that his explanation is: "Everything has its own spirit. Magnetic iron attracts magnetism." The "magnetic" mentioned here is magnetite. The Greeks called amber "elektron" (same as "electric" in English). They imported amber from the Baltic coast and used it to make bracelets and jewelry. Gemstone merchants at the time also knew that rubbing amber could attract feathers, but they thought it was a god or magic. In the East, the Chinese people already had natural knowledge of magnets as early as around 2500 BC. According to "Lu's Spring and Autumn Annals," the Chinese had already had compasses around 1000 BC. They used magnetic needles to identify directions in ancient times. 2. Magnetic, electrostatic The so-called frictional electrification is known only in the BC before it was a phenomenon. For a long time, there has been no progress in understanding this phenomenon. The compass was applied in the navigation of the 13th century. At that time, the compass was a magnet ore that was processed into a needle shape and placed in the straw so that it could float on the water. At the beginning of the 14th century, a sea compass was built with a rope to suspend the needle. This compass played an important role in 1492 when Columbus discovered the New World of the Americas and in 1519 Magellan found a route around the earth. (1) Magnetic, Electrostatic, and Gilbert The Englishman Gilbert was Queen Elizabeth's doctor. He was also a doctor and also studied magnetics. He summed up the experimental results of magnetism over the years and published a book entitled "Magnetism" in 1600. The book points out that the Earth itself is a large magnet and explains the magnetic dip of the compass. Gilbert also studied the phenomenon of friction amber attracting feathers, pointing out that this phenomenon exists not only on amber, but also in sulfur, fur, ceramics, lacquer, paper, silk, metal, rubber, and other frictional electrification materials. The two substances in this series are rubbed against each other, and the substances in the front row of the series will be positively charged and the substances that are behind will be negatively charged. At that time, the main research method was thinking, and he advocated that real research should be based on experiments. He put forward this idea and put it into practice. In this regard, Gilbert is the pioneer of modern scientific research methods. . (2) Thunder and static electricity In China before the year BC, thunder was considered to be God's deed. There are five gods who are responsible for lightning, and their elders are known as Leizu. Under Leizu, they are Leigong and Dianmu. Thunder is thunder and lightning in the sky, lightning is the mother of light with two mirrors to shoot the light down. By the time of Aristotle, it was already more scientific. It is believed that the occurrence of thunder is due to the rise of water vapor on the earth and the formation of thunderclouds. The thunderclouds condense and turn into thunderstorms, accompanied by strong light. It was British Wall who thought that Lei was an electrostatic charge. It was 1708. In 1748, Franklin designed lightning rods based on the same understanding. Can you collect the static electricity in any way? Many scientists have considered this problem. In 1746, Leiden University professor José Brooke invented a static storage bottle, which was later known as the "Leyton Bottle." Lucerne Brooke had previously imagined putting electricity into a bottle as if it contained water in a bottle. He first filled the bottle with water and then used a wire to pull the friction glass rod into the water. In the instant that his hand touched the bottle and the stick, he was heavily "electrically shocked". It is said that he once said: "Even if it is a king's order, I don't want to do this horrible experiment again." Franklin thinks of storing electricity in the Leiden bottle. In June 1752 he made an experiment to put a kite into a thunder cloud. As a result, it was found that sometimes thunderclouds are positively charged and sometimes negatively charged. This kite experiment is very famous. Many scientists are very interested and follow suit. In July 1753, Russian scientist Lehman was unfortunately killed by an electric shock during the experiment. By experimenting with various metals, Volta, a professor at the University of Pavia in Italy, proved that zinc, lead, tin, iron, copper, silver, gold, and graphite are metal voltage series. When the two metals in this series contact each other, The metal in the front row of the series is positive and the metal in the back is negative. He used copper and zinc as two electrodes in dilute sulfuric acid, thus inventing a voltaic cell. The unit of voltage "Volt" is named after him. At the beginning of the 19th century, it was the period of the Napoleonic era after the French Revolution. Napoleon returned from Italy and summoned Voltas to Paris in 1801 to allow him to do electrical experiments. Volta also won the Napoleon gold medal and the Legno-Donor medal. (3) Utilization of voltaic batteries and development of electromagnetics After the invention of the Voltacell, countries used the battery for various experiments and research. Germany conducted electrolyzed water research. The British chemist David connected 2000 voltaic cells and conducted an arc discharge experiment. David's experiment is to install charcoal on the positive and negative electrodes, and emit light by adjusting the distance between the electrodes to generate discharge, which is the beginning of electricity for lighting. In 1820, Oster, a professor at the University of Copenhagen in Denmark, published one of his findings in a paper: a magnetic needle was placed next to the wire connected to a voltaic cell, and the needle immediately deflected. This paper was read by Siringer of Russia. He combined coils with magnetic needles and invented the telegraph (1831). This was the beginning of the telegraph. Later, Ampere in France discovered Ampere's law about the direction of the magnetic field generated around the current (1820). Faraday discovered the epoch-making electromagnetic induction phenomenon (1831), and electromagnetism developed rapidly. On the other hand, research on circuits is also developing. Ohm discovered Ohm's law about resistance (1826), Kirchhoff discovered the law of circuit networks (1849), and established electrical engineering. 3. The history of wired communications Some people say that science and technology are developed because of the needs of the military. This argument has certain historical facts. The United Kingdom was afraid of Napoleon’s offensive and used a trussed telegraph to report its French forces to its own forces. Countries such as Sweden, Germany, and Russia also set up a communications network composed of such communicators for the purpose of military use. Allegedly they have invested a large budget. The concept of transforming such a communication machine into an electric communication method is probably the beginning of wired communication. (1) The principle of wired communication In addition to the electromagnetic telegraph invented by Sirin, which was invented in the above, there is the electrochemical telegraph invented by Jane Merlin of Germany, the telegraph of Gaussian and Weber (Germany), and Cook and Wheaton (UK). 5-pin telegraph etc. The form of the telegraph is also various, including sound type, print type, pointer type, bell type and so on. Among them, Cook and Wheatstone's 5-pin telegraph is best known. In 1837, the telegraph was put into practical use through five wires up to 20 kilometers between London and West Drayton. (2) Morse telegraph In 1837, the Morse telegraph machine was successfully developed in the United States. The inventor was Morse who was famous for Morse code. Morse code is a signal coded in dots or lines. Morse wanted to be an artist. He studied in London for this purpose. In 1815, he listened to Boston University professor Jackson's remarks on the telegraph on the boat back to the United States, and sprouted the concept of Morse code and telegraph. In order to lay the telegraph line, Morse established the Electromagnetism and Telegraph Company, and in 1846 opened a telegraph service between New York-Boston, Philadelphia-Pittsburgh, and Toronto-Buffalo-New York. Morse’s career has been extremely successful, and he has established telegraph companies throughout the United States, and the telegraph business has gradually expanded. In 1846, the Morse telegraphy machine was equipped with a sound receiver and was more convenient to use. (3) Telephones and Switches On February 14, 1876, the two inventors of the United States, Bell and Gray respectively submitted a patent application for a telephone. Bell's application arrived two hours earlier than Gray's application, and Bell received a patent. In 1878, Bell established a telephone company to manufacture telephones and made every effort to develop the telephone business. Since the development of the telephone service, the exchanges have assumed important tasks. Before and after 1877, the switch was called a summons switch. The operator received the call request and it was the subcontractor who gave it to another operator. Later, after repeated improvement, a block diagram type switchboard was developed, and an automatic exchange method was further developed (1879). In 1891, the successful development of the Schrontau-type automatic switch. At this point, the desire for automatic exchange is fulfilled. Afterwards, the research continued and it took several more stages to reach the current electronic switch. (4) Submarine Communication Cable The land-based communications network has gradually become more complete, and people have begun to consider the laying of communication cables on the sea floor to achieve communication between countries across the sea. Around 1840, Wheatstone had already considered the issue of submarine cables. Submarine cables have many problems that need to be solved. The mechanical strength of cables, insulation and laying methods are all different from land cables. In 1845, the English Channel Undersea Telegraph Company was established and began laying submarine cables from Britain to Canada and across the Daval Strait to France. In the laying of submarine cables, major problems such as cable breakage were encountered, but the laying of the bottom cable was a requirement of the times, and all countries contributed to this. In 1851, the earliest installation of the Calais-Dover submarine cable was completed and communication was successfully achieved. As a turning point, many cables were laid around Europe and the eastern part of the Americas. Nowadays, the sea in the world is full of cables for communications. 4. The history of wireless communications Information in any part of the world can be displayed on a television. This convenience is brought to us by radio waves. The earliest radio experiments were conducted in Germany in 1888 by Hertz. Through experiments, Hertz made clear that the waves, like light, have linear propagation, reflection, and refraction. Hertz of frequency is from his name. (1) Marconi's radio device The Italian Marconi, who had read the Hertz experiment article in the magazine, developed the earliest radio device in 1895 and used this device to conduct Morse code communication experiments at a distance of approximately 3 kilometers. He thought of establishing a wireless telegraphy and signaling company to commercialize wireless communications. Despite Marconi’s success in wireless communications, he was opposed to the establishment of a wireless newspaper bureau in Newfoundland because of conflicts with the interests of the submarine cable company. Marconi’s opponents were not few. (2) Generation of high frequency waves To achieve wireless communication, we must first generate stable high-frequency electromagnetic waves. Daddr uses a circuit composed of coils and capacitors to generate high-frequency signals, but the frequency is less than 50KHZ, and the current is only 2~3A, which is relatively small. In 1903, Brunswick of the Netherlands produced a high-frequency wave of 1 MHz using an alcohol vapor arc discharge, and Peterson improved it to make a device with an output power of 1 KW. Later, Germany designed mechanical high-frequency generators. Stella and Fessenden in the United States, Goldschmidt in Germany, and others developed methods for generating high-frequency waves using high-frequency ACs. Many scientists and Engineers have worked on the research of high-frequency wave generators. (3) Wireless Telephone If it is not the Morse signal but the person's language, then there needs to be a carrier carrying the signal. The carrier must be a high frequency wave. In 1906, Alexandrossen of General Electric (GE) of the United States made a high-frequency signal generating device of 80KHZ, and successfully conducted the experiment of wireless telephone for the first time. To transmit a voice with a wireless telephone and to listen to it requires a high-frequency signal generating device for transmission and a detector for reception. Fessenden designed a multi-differential receiver and successfully tested it in 1913. Daddell designed a receiver using the Bowensen arc transmitter as the transmitter and the electrolytic detector as the receiver. At that time, because they all used spark oscillators, they were very noisy. The experimental stage was successful, but it was still far from practical application. In order to stabilize the generated radio waves and receive little noise, one must wait for the appearance of the electron tube. (4) Diodes and Transistors In 1983, Edison discovered that the electrons sputtered from the filaments of a light bulb had blackened part of the bulb, a phenomenon known as the Edison effect. In 1904, Fleming was inspired by the Edison effect, creating a diode and using it for detection. In 1907, the United States. Forrest added an electrode called the gate between the anode and cathode of the diode and invented the triode. This triode can be used to amplify the signal voltage, can also be matched with the appropriate feedback circuit to produce a stable high-frequency signal, it can be said to be an epoch-making circuit component. After further improvement of the triode, it can generate high-frequency signals such as short-wavelength and ultra-shortwave. In addition, the triode has the ability to control the flow of electrons, followed by the appearance of cathode ray tubes and oscilloscopes. 5. Battery history In 1790, Galvani proposed "animal electricity" based on anatomical frog experiments. From this point onwards, Volta found that the two metals have a regular pattern of electricity generation. It can be said that this is the origin of the battery. In 1799, Vodafone sandwiched a layer of paper soaked in salt water between copper and zinc, and then stacked them one by one to make a "voltaic stack." "Electric stack" means to pile up many individual cells together. (1) Primary battery A battery that can no longer be used after the battery is discharged is called a primary battery. Volta made improvements to the voltaic stack and made a voltaic battery. In 1836, the Britishman Daniel put anodes and oxidants in ceramic barrels to make Daniel batteries. Compared to a voltaic battery, the Daniel battery can supply current for a long time. In 1868, the Leclanx of France announced the LeCronchey battery, and in 1885 (Meiji 18), Mizui of Japan first invented the tail well battery. The tail well dry battery is a special battery that absorbs the electrolyte in the sponge and is convenient to carry. In 1917, France's Ferri invented the air battery. In 1940, the American Rubin invented the mercury battery. (2) Secondary battery The battery that can be recharged after discharge is called a secondary battery. In 1859, France's Plantech invented a lead-acid battery that can be used repeatedly. Its structure is that lead acid is contained in dilute sulfuric acid, which is the earliest secondary battery. Now, this type of battery is used in cars. In 1897 (Meiji 30), the Shimadzu source in Japan developed a lead-acid battery with a capacity of 10A*H, and used the prefix GS of his own name GENZO SIMAZU as a trade name, and named the GS battery in the market. In 1899, the Swedish accommodation was made to contain batteries, and in 1905 Edison made Edison batteries. The electrolyte of these batteries uses potassium hydroxide, which is later called an alkaline battery. In 1948, Newman of the United States invented a nickel-cadmium battery. This is a rechargeable battery that is epoch-making battery. (3) Fuel Cell In 1939, the British man Grove discovered that there was electric energy in the reaction of oxygen and hydrogen, and the possibility of the fuel cell was proved by experiments. In other words, when water is electrolyzed, electricity is consumed to generate oxygen and hydrogen. Conversely, oxygen is fed from the outside to the anode, and hydrogen is fed to the cathode to generate electricity and water. Grove was only experimenting and not practical. In 1958, Cambridge University (UK) made a 5KW fuel cell. In 1965, the United States GE company successfully developed a fuel cell, this battery was installed on the manned spacecraft Gemini 5 in 1965, for spacecraft to provide electricity for astronauts drinking water. The power supply on the Apollo 11 spacecraft that landed on the moon in 1969 also used a fuel cell as the power source inside the spacecraft. (4) Solar Cells In 1873, German Siemens invented a photocell made of selenium and platinum wire. This selenium photocell is now used on camera exposure meters. In 1945, the American summer product invented a silicon solar cell, which is a component that can generate electrical energy when sunlight or light shines on its PN junction. It is widely used in artificial satellites, solar cars, clocks, and desktop calculators. . Research and development efforts to improve the conversion efficiency of such components are still in progress. 6. The history of lighting The industrial revolution initiated in Britain in the 1860s enabled the factory to enter continuous processing. In the era of mass production, night lighting became an important issue. As already mentioned, the British David Dave had done a famous experiment in 2000 with arc welding with 2000 volt batteries. (1) Incandescent light bulbs In 1860, the British Swan made a carbon filament into a glass bulb after carbonization and invented a carbon filament bulb. However, because the vacuum technology was not high at the time, the lighting time could not be too long. Over time, the filament would oxidize and burn in the bulb. The principle of the incandescent light bulb Swan thinks of is the origin of the modern white light. With the advancement of filament research and vacuum technology, incandescent lamps have finally become practical. From this point not to say, Swan's invention is a great invention. In 1865, Sprengel developed a mercury vacuum pump for the study of vacuum phenomena. After Swan knew about it, he increased the vacuum inside the glass bulb in 1878, and he made some efforts in the filament. He first treated the cotton with sulfuric acid and then carbonized it. Finally, he announced the Swann bulb. Swan's incandescent bulbs were exhibited at the Paris International Exhibition. In 1879, Edison of the United States succeeded in extending the life of incandescent bulbs to more than 40 hours. In 1880, Edison found that bamboo was an excellent material for incandescent filaments. He collected bamboo from Japan, China, and India and experimented repeatedly. Edison sent Moore to Japan to search for high-quality bamboo in Kyoto's gossip. A few years later, he created a filament from eight bamboos. In order to manufacture this bulb of bamboo filament, he founded Edison Electric Company in London and New York in 1882. In Japan, Tokyo Electric Company was established in 1886 (Meiji 19). Since the Meiji period in 22, general families have begun to use white light bulbs. In 1910, the U.S. Kure Hall used tungsten filaments to invent tungsten filament bulbs. In 1913, America's Lanmere filled the glass bulb to prevent the filament from evaporating and invented the gas-filled tungsten bulb. In 1925, Japan's not broken orange invented the inner wall frosted bulbs. In 1932, Japan's Miura Suichi invented a double-helix tungsten bulb. It is because of the constant exploration above that today we can enjoy the daily life of incandescent lighting, and it is really a long road to think of it. (2) Discharge lamps In 1902, Hewitz in the United States loaded mercury vapor into a glass bulb and invented an arc discharge mercury lamp. Since this mercury lamp emits a large amount of ultraviolet rays when the pressure of mercury vapor is low, it is often used as a germicidal lamp. When the mercury gas pressure is high, strong visible light can be emitted. The light emitted by high-pressure mercury lamps, which are widely used in square lighting and road lighting, is a kind of mixed light. The mixed light includes mercury arc discharge light and ultraviolet light emitted by the fluorescent material coated on the inner wall of the glass bulb. In 1932, Philips of the Netherlands developed a monochromatic sodium lamp with a wavelength of 590 nm, which is widely used for tunnel lighting of highways. In 1938, Inman of the United States invented the now widely used fluorescent lamps. This lamp emits light of different colors by irradiating ultraviolet rays emitted from a mercury arc discharge to irradiate different phosphors coated on the inner wall of the lamp tube. In general, white fluorescent lamps are used most often. 7. The history of electrical equipment It can be said that the electromagnetic action discovered by Auster in 1820 was the origin of the motor. The electromagnetic induction discovered by Faraday in 1831 was the origin of the generator's transformer. (1) Generator In 1832, the Frenchman Bixisi invented a hand-cranked DC generator. Its principle is to generate a induced electromotive force in a coil by turning a permanent magnet to change the magnetic flux, and to output this electromotive force as a DC voltage. In 1866, Siemens in Germany invented a self-excited DC generator. In 1869, Belgium's Gram made a ring armature and invented the ring armature generator. This type of generator uses water to rotate the rotor of the generator, and after repeated improvement, the output power of 3.2 KW was obtained in 1847. In 1882, Gordon of the United States produced a two-phase giant generator with an output power of 447 kW, a height of 3 meters and a weight of 22 tons. Tesla of the United States decided to develop AC motors at Edison. However, since Edison insisted that he only use DC, he sold the patents for two-phase alternators and motors to Westinghouse. In 1896, Tesla's two-phase alternator began operation at the Nyala Power Plant. 3,750 kW, 5000V AC was delivered to Buffalo, 40 kilometers away. In 1889, Westinghouse built a power plant in Oregon and in 1892 successfully delivered 15,000 volts to Pittsfield. (2) Motor In 1834, Russia's Jacobi produced a DC motor consisting of electromagnets. In 1838, this kind of motor started a boat and the motor power used 320 batteries. In addition, Winport in the United States and Debideson in the United Kingdom also created a DC motor (1836) as a power device for printing presses. Since these motors are all battery-powered, they are not widely used. In 1887, the previously mentioned Tesla two-phase motor was started as a development plan for a practical induction motor. In 1897, Westinghouse made an induction motor and set up a professional company dedicated to the popularity of electric motors. (3) Transformers When the power generation terminal transfers AC power to the outside, it must first increase the AC voltage to the power end, and then must reduce the AC voltage sent. Therefore, transformers are essential. In 1831, Faraday discovered that magnetic induction can generate electricity, which is the basis for the birth of a transformer. In 1882, Gibbs of the United Kingdom obtained a patent on the "power distribution method for lighting and power". Its content was to use transformers for power distribution. The transformers used at the time were magnetic circuit open transformers. Westinghouse introduced Gibbs' transformers. After research, it developed a practical transformer in 1885. In addition, in the year before 1884, the British Hopkinson made a closed magnetic circuit type transformer. (4) Power equipment and three-phase AC technology Two-phase alternating current is a technique that uses four wires to transmit power. Germany's Dobrowowski figured out the tricks on the windings, drawing taps from three places every 120 degrees on the windings to obtain three-phase alternating current. In 1889, using the rotating magnetic field of this three-phase alternating current, the earliest three-phase AC motor with a power of 100W was made. In the same year, Dobrowowski developed a three-phase, four-wire AC connection and achieved success in the 1891 Frankfurt experiment (150VA three-phase transformer). 8. The history of electronic circuit components In the modern era, electronics, including computers, is prospering. The background and electronic circuit components are closely related to the continuous development of electronic tube-transistors and integrated circuits. (1) Tube The electron tubes were invented along the order of the diode-transistor-tetrode-pentode. Diode: As previously mentioned, Edison discovered the “Edison effect†of the electron emission from the bulb filament. In 1904, the British Fleming was inspired by the "Edison effect" and invented the diode. Triode: In 1907, Forrest of the United States invented the triode. At that time, vacuum technology was not yet mature and the manufacturing level of triodes was not high. However, in the process of repeated improvement, people understood that the triode has amplifying effect and finally opened the curtain of electronics. The oscillator also evolved from a Marconi spark device as discussed above to a triode oscillator. The triode has three electrodes, an anode, a cathode, and a control gate disposed therebetween. This control gate is used to control the electron current emitted from the cathode. The tetrode: In 1915, Britain's Lande added an electrode between the control electrode and the anode of the triode, called the curtain grid, to solve the problem that part of the electron current flowing to the anode in the triode will flow to the cathode. Control the issue of the gate. The pentode: In 1927, Joebest in Germany added another electrode between the anode and the curtain grid, inventing the pentode. The newly added electrode is called a suppression gate. The reason for adding this electrode is that in the tetrode, when the electron current hits the anode, the anode generates secondary electron emission, and the suppression gate is set to suppress the secondary electron emission. In addition, in 1934, Tom Green of the United States invented an acorn tube suitable for ultra-shortwaves by miniaturizing and improving the electron tube. The ST tube using metal instead of glass was invented in 1937. The miniaturized MT tube was invented in 1939. (2) Transistors Semiconductor devices are broadly divided into two major parts: transistors and integrated circuits (ICs). After the Second World War, due to the advancement of semiconductor technology, electronics has achieved remarkable development. The transistor was invented by Shockley, Badin, Blatter of Bell Labs in the United States in 1948. The structure of this transistor is to make two wires in contact with the surface of the low-doped germanium semiconductor, which is called contact transistor. In 1949, junction transistors were developed and a major step forward was made in practical use. In 1956, a diffusion method for manufacturing P-type and N-type semiconductors was developed. It is a method of infiltrating impurity atoms into the surface of semiconductors at high temperatures. In 1960, an epitaxial growth method was developed and an epitaxial planar transistor was manufactured. Epitaxial growth is a method of manufacturing semiconductors by placing silicon crystals in hydrogen and halide gases. With these developments in semiconductor technology, integrated circuits were born. (3) Integrated Circuits Around 1956, Dyna, England, predicted the emergence of integrated circuits from transistor principles. In 1958, the United States proposed a method of manufacturing all circuit components using semiconductors to realize integrated circuits. In 1961, Texas Instruments began mass production of integrated circuits. An integrated circuit is not a circuit that is connected by one circuit component, but a device that "buries" a circuit with a certain function in a semiconductor crystal. It is easy to miniaturize and reduce the lead end, so it has the advantage of high reliability. The degree of integration of integrated circuits has increased year by year. Small-scale integrated circuits with 100 or fewer components, 100 to 1,000 medium- and large-scale integrated circuits, 1,000 to 100,000 large-scale integrated circuits, and 100,000 or more ultra-large-scale integrated circuits have all been developed in turn. The device has been widely used.
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