History of mobile phones
The history of mobile phones covers mobile communication devices that connect wirelessly to the public switched telephone network. While the transmission of speech by radio has a long history, the first devices that were wireless and capable of connecting to the standard telephone network are much more recent; the first such devices were portable compared to today's compact hand-held devices, their use was clumsy. Along with the process of developing a more portable technology, a better interconnections system, drastic changes have taken place in both the networking of wireless communication and the prevalence of its use, with smartphones becoming common globally and a growing proportion of Internet access now done via mobile broadband. Before the devices existed that are now referred to as mobile phones or cell phones, there were some precursors. In 1908, a Professor Albert Jahnke and the Oakland Transcontinental Aerial Telephone and Power Company claimed to have developed a wireless telephone.
They were accused of fraud and the charge was dropped, but they do not seem to have proceeded with production. Beginning in 1918, the German railroad system tested wireless telephony on military trains between Berlin and Zossen. In 1924, public trials started with telephone connection on trains between Hamburg. In 1925, the company Zugtelephonie AG was founded to supply train telephony equipment and, in 1926, telephone service in trains of the Deutsche Reichsbahn and the German mail service on the route between Hamburg and Berlin was approved and offered to first-class travelers. Fiction anticipated the development of real world mobile telephones. In 1906, the English caricaturist Lewis Baumer published a cartoon in Punch magazine entitled "Forecasts for 1907" in which he showed a man and a woman in London's Hyde Park each separately engaged in gambling and dating on wireless telephony equipment. In 1926, the artist Karl Arnold created a visionary cartoon about the use of mobile phones in the street, in the picture "wireless telephony", published in the German satirical magazine Simplicissimus.
The Second World War made military use of radio telephony links. Hand-held radio transceivers have been available since the 1940s. Mobile telephones for automobiles became available from some telephone companies in the 1940s. Early devices were bulky, consumed large amounts of power, the network supported only a few simultaneous conversations. Modern cellular networks allow automatic and pervasive use of mobile phones for voice and data communications. In the United States, engineers from Bell Labs began work on a system to allow mobile users to place and receive telephone calls from automobiles, leading to the inauguration of mobile service on June 17th 1946 in St. Louis, Missouri. Shortly after, AT&T offered Mobile Telephone Service. A wide range of incompatible mobile telephone services offered limited coverage area and only a few available channels in urban areas; the introduction of cellular technology, which allowed re-use of frequencies many times in small adjacent areas covered by low powered transmitters, made widespread adoption of mobile telephones economically feasible.
In the USSR, Leonid Kupriyanovich, an engineer from Moscow, in 1957-1961 developed and presented a number of experimental pocket-sized communications radio. The weight of one model, presented in 1961, could fit on a palm. However, in the USSR the decision at first to develop the system of the automobile "Altai" phone was made. In 1965, the Bulgarian company "Radioelektronika" presented a mobile automatic phone combined with a base station at the Inforga-65 international exhibition in Moscow. Solutions of this phone were based on a system developed by Leonid Kupriyanovich. One base station, connected to one telephone wire line, could serve up to 15 customers; the advances in mobile telephony can be traced in successive generations from the early "0G" services like MTS and its successor Improved Mobile Telephone Service, to first-generation analog cellular network, second-generation digital cellular networks, third-generation broadband data services to the state-of-the-art, fourth-generation native-IP networks.
In 1949, AT&T commercialized Mobile Telephone Service. From its start in St. Louis, Missouri, in 1946, AT&T introduced Mobile Telephone Service to one hundred towns and highway corridors by 1948. Mobile Telephone Service was a rarity with only 5,000 customers placing about 30,000 calls each week. Calls were set up manually by an operator and the user had to depress a button on the handset to talk and release the button to listen; the call subscriber equipment weighed about 80 pounds Subscriber growth and revenue generation were hampered by the constraints of the technology. Because only three radio channels were available, only three customers in any given city could make mobile telephone calls at one time. Mobile Telephone Service was expensive, costing US$15 per month, plus $0.30–0.40 per local call, equivalent to about $176 per month and $3.50–4.75 per call. In the UK, there was a vehicle-based system called "Post Office Radiophone Service,", launched around the city of Manchester in 1959, although it required callers to speak to an operator, it was possible to be put through to any subscriber in Great Britain.
The service was extended to London in 1965 and other major cities in 1972. AT&T introduced the first major improvement to mobile telephony in 1965, giving the improved service the obvious name of Improved Mobile Telephone Service. IMTS used additional radio channels, allowing more simultaneous calls in a given geographic area, introduced customer dialing, eliminating manual call setup by an operator, reduced the size and weight of the subscriber equipment. Desp
Charles K. Kao
Sir Charles Kuen Kao was a physicist and electrical engineer who pioneered the development and use of fibre optics in telecommunications. In the 1960s, Kao created various methods to combine glass fibres with lasers in order to transmit digital data, which laid the groundwork for the evolution of the Internet. Known as the "Godfather of Broadband", the "Father of Fiber Optics", the "Father of Fiber Optic Communications", Kao was awarded the 2009 Nobel Prize in Physics for "groundbreaking achievements concerning the transmission of light in fibers for optical communication". Born in Shanghai, Kao was a permanent resident of Hong Kong and held citizenships in the United Kingdom and the United States. Charles Kao was born in Shanghai, China in 1933, his ancestral home is in nearby Jinshan, at that time a separate administrative area, he studied Chinese classics at home under a tutor. He studied English and French at an international school in Shanghai French Concession, founded by a number of progressive Chinese educators including Cai Yuanpei.
Kao's family moved to Taiwan and British Hong Kong in 1948 where he completed his secondary education at St. Joseph's College in 1952, he did his undergraduate studies in electrical engineering at Woolwich Polytechnic, obtaining his Bachelor of Engineering degree. He pursued research and received his PhD in electrical engineering in 1965 from University of London, under Professor Harold Barlow of University College London as an external student while working at Standard Telecommunication Laboratories in Harlow, the research centre of Standard Telephones and Cables, it is there that Kao did his first groundbreaking work as an engineer and researcher working alongside George Hockham under the supervision of Alec Reeves. Kao's father Kao Chun-Hsiang was a lawyer who obtained his J. D. from the University of Michigan Law School in 1925. He was a professor at Soochow University Comparative Law School of China, his grandfather was Gao Xie, a famous scholar, literator, a leading figure of the South Society during the late Qing Dynasty.
Some influential writers including Gao Xu, Yao Guang, Gao Zeng were Gao's close relatives. His father's cousin was astronomer Kao Ping-tse. Kao has a younger brother named Timothy Wu Kao, a civil engineer and Professor Emeritus at the Catholic University of America in Washington, D. C, his research is in hydrodynamics. Kao met his future wife Gwen May-Wan Kao in London after graduation, when they worked together as engineers at Standard Telephones and Cables, she is British Chinese. They were married in 1959 in London, had two children, a son and a daughter, both of whom reside and work in Silicon Valley, California. According to Kao's autobiography, Kao was a Catholic who attended Catholic Church while his wife attended Anglican Communion. In the 1960s at Standard Telecommunication Laboratories based in Harlow, Essex and his co-workers did their pioneering work in the realisation of fibre optics as a telecommunications medium, by demonstrating that the high-loss of existing fibre optics arose from impurities in the glass, rather than from an underlying problem with the technology itself.
In 1963, when Kao first joined the optical communications research team he made notes summarising the background situation and available technology at the time, identifying the key individuals involved. Kao worked in the team of Antoni E. Karbowiak, working under Alec Reeves to study optical waveguides for communications. Kao's task was to investigate fibre attenuation, for which he collected samples from different fibre manufacturers and investigated the properties of bulk glasses carefully. Kao's study convinced himself that the impurities in material caused the high light losses of those fibres; that year, Kao was appointed head of the electro-optics research group at STL. He took over the optical communication program of STL in December 1964, because his supervisor, left to take the Chair in Communications in the School of Electrical Engineering at the University of New South Wales, Australia. Although Kao succeeded Karbowiak as manager of optical communications research, he decided to abandon Karbowiak's plan and overall change research direction with his colleague George Hockham.
They not only considered optical physics but the material properties. The results were first presented by Kao to the IEE in January 1966 in London, further published in July with George Hockham; this study first theorized and proposed to use glass fibres to implement optical communication, the ideas described are the basis of today's optical fibre communications. In 1965, Kao with Hockham concluded that the fundamental limitation for glass light attenuation is below 20 dB/km, a key threshold value for optical communications. However, at the time of this determination, optical fibres exhibited light loss as high as 1,000 dB/km and more; this conclusion opened the intense race to find low-loss materials and suitable fibres for reaching such criteria. Kao, together with his new team, pursued this goal by testing various materials, they measured the attenuation of light with different wavelengths in glasses
Video is an electronic medium for the recording, playback and display of moving visual media. Video was first developed for mechanical television systems, which were replaced by cathode ray tube systems which were replaced by flat panel displays of several types. Video systems vary in display resolution, aspect ratio, refresh rate, color capabilities and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, computer files, network streaming. Video technology was first developed for mechanical television systems, which were replaced by cathode ray tube television systems, but several new technologies for video display devices have since been invented. Video was exclusively a live technology. Charles Ginsburg led an Ampex research team developing one of the first practical video tape recorder. In 1951 the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape.
Video recorders were sold for US $50,000 in 1956, videotapes cost US $300 per one-hour reel. However, prices dropped over the years; the use of digital techniques in video created digital video, which allows higher quality and much lower cost than earlier analog technology. After the invention of the DVD in 1997 and Blu-ray Disc in 2006, sales of videotape and recording equipment plummeted. Advances in computer technology allows inexpensive personal computers and smartphones to capture, store and transmit digital video, further reducing the cost of video production, allowing program-makers and broadcasters to move to tapeless production; the advent of digital broadcasting and the subsequent digital television transition is in the process of relegating analog video to the status of a legacy technology in most parts of the world. As of 2015, with the increasing use of high-resolution video cameras with improved dynamic range and color gamuts, high-dynamic-range digital intermediate data formats with improved color depth, modern digital video technology is converging with digital film technology.
Frame rate, the number of still pictures per unit of time of video, ranges from six or eight frames per second for old mechanical cameras to 120 or more frames per second for new professional cameras. PAL standards and SECAM specify 25 frame/s. Film is shot at the slower frame rate of 24 frames per second, which complicates the process of transferring a cinematic motion picture to video; the minimum frame rate to achieve a comfortable illusion of a moving image is about sixteen frames per second. Video can be progressive. In progressive scan systems, each refresh period updates all scan lines in each frame in sequence; when displaying a natively progressive broadcast or recorded signal, the result is optimum spatial resolution of both the stationary and moving parts of the image. Interlacing was invented as a way to reduce flicker in early mechanical and CRT video displays without increasing the number of complete frames per second. Interlacing retains detail while requiring lower bandwidth compared to progressive scanning.
In interlaced video, the horizontal scan lines of each complete frame are treated as if numbered consecutively, captured as two fields: an odd field consisting of the odd-numbered lines and an field consisting of the even-numbered lines. Analog display devices reproduce each frame doubling the frame rate as far as perceptible overall flicker is concerned; when the image capture device acquires the fields one at a time, rather than dividing up a complete frame after it is captured, the frame rate for motion is doubled as well, resulting in smoother, more lifelike reproduction of moving parts of the image when viewed on an interlaced CRT display. NTSC, PAL and SECAM are interlaced formats. Abbreviated video resolution specifications include an i to indicate interlacing. For example, PAL video format is described as 576i50, where 576 indicates the total number of horizontal scan lines, i indicates interlacing, 50 indicates 50 fields per second; when displaying a natively interlaced signal on a progressive scan device, overall spatial resolution is degraded by simple line doubling—artifacts such as flickering or "comb" effects in moving parts of the image which appear unless special signal processing eliminates them.
A procedure known as deinterlacing can optimize the display of an interlaced video signal from an analog, DVD or satellite source on a progressive scan device such as an LCD television, digital video projector or plasma panel. Deinterlacing cannot, produce video quality, equivalent to true progressive scan source material. Aspect ratio describes the proportional relationship between the width and height of video screens and video picture elements. All popular video formats are rectangular, so can be described by a ratio between width and height; the ratio width to height for a traditional television screen is 4:3, or about 1.33:1. High definition televisions use an aspect ratio of 16:9, or about 1.78:1. The aspect ratio of a full 35 mm film frame with soundtrack is 1.375:1. Pixels on computer monitors are square, but pixels used in digital video have non-square aspect ratios, such as those used in the PAL and NTSC variants of the CCIR 601 digital video
Reginald Aubrey Fessenden was a Canadian-born inventor, who did a majority of his work in the United States and claimed U. S. citizenship through his American-born father. During his life he received hundreds of patents in various fields, most notably ones related to radio and sonar. Fessenden is best known for his pioneering work developing radio technology, including the foundations of amplitude modulation radio, his achievements included the first transmission of speech by radio, the first two-way radiotelegraphic communication across the Atlantic Ocean. In 1932 he reported that, in late 1906, he made the first radio broadcast of entertainment and music, although a lack of verifiable details has led to some doubts about this claim. Reginald Fessenden was born October 6, 1866, in East-Bolton, the eldest of the Reverend Elisha Joseph Fessenden and Clementina Trenholme's four children. Elisha Fessenden was a Church of England in Canada minister, the family moved to a number of postings throughout the province of Ontario.
While growing up, Fessenden attended a number of educational institutions. At the age of nine, he was enrolled in the DeVeaux Military school for a year, he next attended Trinity College School in Port Hope, from 1877 until the summer of 1879. He spent a year working for the Imperial Bank at Woodstock, because he had not yet reached the age of 16 needed to enroll in college. At the age of fourteen, Bishop's College School in Lennoxville, a feeder school for Bishop's College and shared the same campus and buildings, granted him a mathematics mastership. Thus, while Fessenden was still a teenager, he taught mathematics to the younger students at the School, while studying with older students at the College. At the age of eighteen, Fessenden left Bishop's without having been awarded a degree, although he had "done all the work necessary", in order to accept a position at the Whitney Institute in Bermuda, where for the next two years he worked as the principal and sole teacher. While in Bermuda, he became engaged to Helen Trott.
They married in September 1890 and had a son, Reginald Kennelly Fessenden. Fessenden's classical education provided him with only a limited amount of scientific and technical training. Interested in increasing his skills in the electrical field, he moved to New York City in 1886, with hopes of gaining employment with the famous inventor, Thomas Edison. However, his initial attempts were rebuffed. However, Fessenden persevered, before the end of the year was hired for a semi-skilled position as an assistant tester for the Edison Machine Works, laying underground electrical mains in New York City, he proved his worth, received a series of promotions, with increasing responsibility for the project. In late 1886, Fessenden began working directly for Edison at the inventor's new laboratory in West Orange, New Jersey as a junior technician, he participated in a broad range of projects, which included work in solving problems in chemistry and electricity. However, in 1890, facing financial problems, Edison was forced to lay off most of the laboratory employees, including Fessenden.
Taking advantage of his recent practical experience, Fessenden was able to find positions with a series of manufacturing companies. In 1892, he received an appointment as professor for the newly formed Electrical Engineering department at Purdue University in West Lafayette, Indiana; that year, George Westinghouse recruited Fessenden for the newly created position of chair of the Electrical Engineering department at the Western University of Pennsylvania in Pittsburgh. In the late 1890s, reports began to appear about the success Guglielmo Marconi was having in developing a practical system of transmitting and receiving radio signals commonly known as "wireless telegraphy". Fessenden began limited radio experimentation, soon came to the conclusion that he could develop a far more efficient system than the spark-gap transmitter and coherer-receiver combination, created by Oliver Lodge and Marconi. By 1899 he was able to send radiotelegraph messages between Pittsburgh and Allegheny City, using a receiver of his own design.
In 1900 Fessenden left Pittsburgh to work for the United States Weather Bureau, with the objective of demonstrating the practicality of using coastal stations to transmit weather information, thereby avoiding the expense of the existing telegraph lines. The contract called for him to be paid $3,000 per year and provided with work space and housing. Fessenden would retain ownership of any inventions, but the agreement gave the Weather Bureau royalty-free use of any discoveries made during the term of the contract. Fessenden made major advances in receiver design, as he worked to develop audio reception of signals, his initial success came from the invention of a barretter detector. This was followed by an elect
History of videotelephony
The history of videotelephony covers the historical development of several technologies which enable the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its earliest trials would take nearly a half century to be discovered; this was first embodied in the device which came to be known as the video telephone, or videophone, it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony and television. The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs; this occurred in part, at least with AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications.
However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones. Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Expensive videoconferencing systems evolved throughout the 1980s and 1990s from proprietary equipment and network requirements to standards-based technologies that were available to the general public at a reasonable cost. Only in the late 20th century with the advent of powerful video codecs combined with high-speed Internet broadband and ISDN service did videotelephony become a practical technology for regular use. With the rapid improvements and popularity of the Internet, videotelephony has become widespread through the deployment of video-enabled mobile phones, plus videoconferencing and computer webcams which utilize Internet telephony. In the upper echelons of government and commerce, telepresence technology, an advanced form of videoconferencing, has helped reduce the need to travel.
Two years after the telephone was first patented in the United States in 1876 by Dr. Alexander Graham Bell, an early concept of a combined videophone and wide-screen television called a telephonoscope was conceptualized in the popular periodicals of the day, it was mentioned in various early science fiction works such as Le Vingtième siècle. La vie électrique and other works written by Albert Robida, was sketched in various cartoons by George du Maurier as a fictional invention of Thomas Edison. One such sketch was published on December 1878 in Punch magazine; the term'telectroscope' was used in 1878 by French writer and publisher Louis Figuier, to popularize an invention wrongly interpreted as real and incorrectly ascribed to Dr. Bell after his Volta Laboratory discreetly deposited a sealed container of a Graphophone phonograph at the Smithsonian Institution for safekeeping. Written under the pseudonym "Electrician", one article earlier claimed that "an eminent scientist" had invented a device whereby objects or people anywhere in the world "....could be seen anywhere by anybody".
The device, among other functions, would allow merchants to transmit pictures of their wares to their customers, the contents of museum collections to be made available to scholars in distant cities...." In the era prior to the advent of broadcasting, electrical "seeing" devices were conceived as adjuncts to the telephone, thus creating the concept of a videophone. Fraudulent reports of'amazing' advances in video telephones would be publicized as early as 1880 and would reoccur every few years, such as the episode of'Dr. Sylvestre' of Paris who claimed in 1902 to have invented a powerful video telephone, termed a'spectograph', the intellectual property rights he believed were worth $5,000,000. After reviewing his claim Dr. Bell denounced the supposed invention as a "fairy tale", publicly commented on the charlatans promoting bogus inventions for financial gain or self-promotion; however Dr. Alexander Graham Bell thought that videotelephony was achievable though his contributions to its advancement were incidental.
In April 1891, Dr. Bell did record conceptual notes on an'electrical radiophone', which discussed the possibility of "seeing by electricity" using devices that employed tellurium or selenium imaging components. Bell wrote, decades prior to the invention of the image dissector: Should it be found... is illuminated an apparatus might be constructed in which each piece of selenium is a mere speck, like the head of a small pin, the smaller the better. The darkened selenium should be placed in a cup-like receiver which can fit over the eye... When the first selenium speck is presented to an illuminated object, it may be possible that the eye in the darkened receiver, should perceive, not light, but an image of the object... Bell went on to predict that: "...the day would come when the man at the telephone would be able to see the distant person to whom he was speaking." The discoveries in physics and materials science underlying video technology would not be in place until the mid-1920s, first being utilized in electromechanical television.
More practical'all-electronic' video and television would not emerge until 1939, but would suffer several more years of delays before gaining popularity due to the onset and effects of World War II. The compound name'videophone' entered into general usage after 1950, although'video telephone' entered the lexicon earlier after video was coined in 1935. Prior to that time there appeared to be no standard terms for'video telephone', with exp
Lee de Forest
Lee de Forest was an American inventor, self-described "Father of Radio", a pioneer in the development of sound-on-film recording used for motion pictures. He had over 180 patents, but a tumultuous career—he boasted that he made lost, four fortunes, he was involved in several major patent lawsuits, spent a substantial part of his income on legal bills, was tried for mail fraud. His most famous invention, in 1906, was the three-element "Audion" vacuum tube, the first practical amplification device. Although De Forest had only a limited understanding of how it worked, it was the foundation of the field of electronics, making possible radio broadcasting, long distance telephone lines, talking motion pictures, among countless other applications. Lee de Forest was born in 1873 in Council Bluffs, the son of Anna Margaret and Henry Swift DeForest, he was a direct descendant of Jessé de Forest, the leader of a group of Walloon Huguenots who fled Europe in the 17th century due to religious persecution.
De Forest's father was a Congregational Church minister who hoped his son would become a pastor. In 1879 the elder de Forest became president of the American Missionary Association's Talladega College in Talladega, Alabama, a school "open to all of either sex, without regard to sect, race, or color", which educated African-Americans. Many of the local white citizens resented the school and its mission, Lee spent most of his youth in Talladega isolated from the white community, with several close friends among the black children of the town. De Forest prepared for college by attending Mount Hermon Boys' School in Mount Hermon, Massachusetts for two years, beginning in 1891. In 1893, he enrolled in a three-year course of studies at Yale University's Sheffield Scientific School in New Haven, Connecticut, on a $300 per year scholarship, established for relatives of David de Forest. Convinced that he was destined to become a famous—and rich—inventor, perpetually short of funds, he sought to interest companies with a series of devices and puzzles he created, expectantly submitted essays in prize competitions, all with little success.
After completing his undergraduate studies, in September 1896 de Forest began three years of postgraduate work. However, his electrical experiments had a tendency to blow fuses. After being warned to be more careful, he managed to douse the lights during an important lecture by Professor Charles Hastings, who responded by having de Forest expelled from Sheffield. With the outbreak of the Spanish–American War in 1898, de Forest enrolled in the Connecticut Volunteer Militia Battery as a bugler, but the war ended and he was mustered out without leaving the state, he completed his studies at Yale's Sloane Physics Laboratory, earning a Doctorate in 1899 with a dissertation on the "Reflection of Hertzian Waves from the Ends of Parallel Wires", supervised by theoretical physicist Willard Gibbs. De Forest was convinced there was a great future in radiotelegraphic communication, but Italian Guglielmo Marconi, who received his first patent in 1896, was making impressive progress in both Europe and the United States.
One drawback to Marconi's approach was his use of a coherer as a receiver, while providing for permanent records, was slow and not reliable. De Forest was determined to devise a better system, including a self-restoring detector that could receive transmissions by ear, thus making it capable of receiving weaker signals and allowing faster Morse code sending speeds. After making unsuccessful inquiries about employment with Nikola Tesla and Marconi, de Forest struck out on his own, his first job after leaving Yale was with the Western Electric Company's telephone lab in Chicago, Illinois. While there he developed his first receiver, based on findings by two German scientists, Drs. A. Neugschwender and Emil Aschkinass, their original design consisted of a mirror in which a narrow, moistened slit had been cut through the silvered back. Attaching a battery and telephone receiver, they could hear sound changes in response to radio signal impulses. De Forest, along with Ed Smythe, a co-worker who provided financial and technical help, developed variations they called "responders".
A series of short-term positions followed, including three unproductive months with Professor Warren S. Johnson's American Wireless Telegraph Company in Milwaukee and work as an assistant editor of the Western Electrician in Chicago. With radio research his main priority, de Forest next took a night teaching position at the Lewis Institute, which freed him to conduct experiments at the Armour Institute. By 1900, using a spark-coil transmitter and his responder receiver, de Forest expanded his transmitting range to about seven kilometers. Professor Clarence Freeman of the Armour Institute became interested in de Forest's work and developed a new type of spark transmitter. De Forest soon felt that Smythe and Freeman were holding him back, so in the fall of 1901 he made the bold decision to go to New York to compete directly with Marconi in transmitting race results for the International Yacht races. Marconi had made arrangements to provide reports for the Associated Press, which he had done for the 1899 contest.
De Forest contracted to do the same for the smaller Publishers' Press Association. The race effort turned out to be an total failure; the Freeman transmitter broke down — in a fit of rage, de Forest threw it overboard — and had to be replaced by an ordinary spark coil
Jagadish Chandra Bose
Sir Jagadish Chandra Bose spelled Jagdish and Jagadis, was a polymath, biologist, biophysicist and archaeologist, an early writer of science fiction from India. He pioneered the investigation of radio and microwave optics, made significant contributions to plant science, laid the foundations of experimental science in the Indian subcontinent. IEEE named him one of the fathers of radio science. Bose is considered the father of Bengali science fiction, invented the crescograph, a device for measuring the growth of plants. A crater on the moon has been named in his honour. Born in Munsiganj, Bengal Presidency, during British governance of India, Bose graduated from St. Xavier's College, Calcutta, he went to the University of London to study medicine, but could not pursue studies in medicine because of health problems. Instead, he conducted his research with the Nobel Laureate Lord Rayleigh at Cambridge and returned to India, he joined the Presidency College of the University of Calcutta as a professor of physics.
There, despite racial discrimination and a lack of funding and equipment, Bose carried on his scientific research. He made remarkable progress in his research of remote wireless signalling and was the first to use semiconductor junctions to detect radio signals. However, instead of trying to gain commercial benefit from this invention, Bose made his inventions public in order to allow others to further develop his research. Bose subsequently made a number of pioneering discoveries in plant physiology, he used his own invention, the crescograph, to measure plant response to various stimuli, thereby scientifically proved parallelism between animal and plant tissues. Although Bose filed for a patent for one of his inventions because of peer pressure, his objections to any form of patenting was well known. To facilitate his research, he constructed automatic recorders capable of registering slight movements, his books include Response in The Nervous Mechanism of Plants. In 2004, Bose was ranked number 7 in BBC's poll of the Greatest Bengali of all time.
Jagadish Chandra Bose was born in a Bengali Kayastha family in Munsiganj, Bengal Presidency on 30 November 1858. His father, Bhagawan Chandra Bose, was a leading member of the Brahmo Samaj and worked as a deputy magistrate and assistant commissioner in Faridpur and other places. Bose's education started in a vernacular school, because his father believed that one must know one's own mother tongue before beginning English, that one should know one's own people. Speaking at the Bikrampur Conference in 1915, Bose said: At that time, sending children to English schools was an aristocratic status symbol. In the vernacular school, to which I was sent, the son of the Muslim attendant of my father sat on my right side, the son of a fisherman sat on my left, they were my playmates. I listened spellbound to their stories of birds and aquatic creatures; these stories created in my mind a keen interest in investigating the workings of Nature. When I returned home from school accompanied by my school fellows, my mother welcomed and fed all of us without discrimination.
Although she was an orthodox old-fashioned lady, she never considered herself guilty of impiety by treating these ‘untouchables’ as her own children. It was because of my childhood friendship with them that I could never feel that there were ‘creatures’ who might be labelled'low-caste'. I never realised that there existed a'problem' common to the two communities and Muslims. Bose joined the Hare School in 1869 and St. Xavier's School at Kolkata. In 1875, he passed the Entrance Examination of the University of Calcutta and was admitted to St. Xavier's College, Calcutta. At St. Xavier's, Bose came in contact with Jesuit Father Eugene Lafont, who played a significant role in developing his interest in natural sciences, he received a BA from the University of Calcutta in 1879. Bose wanted to go to England to compete for the Indian Civil Service. However, his father, a civil servant himself, cancelled the plan, he wished his son to be a scholar, who would “rule nobody but himself.” Bose went to England to study Medicine at the University of London.
However, he had to quit because of ill health. The odour in the dissection rooms is said to have exacerbated his illness. Through the recommendation of Anandamohan Bose, his brother-in-law and the first Indian wrangler, he secured admission in Christ's College, Cambridge to study natural sciences, he received a BA from the University of Cambridge and a BSc from the University of London in 1884, a DSc from the University of London in 1896. Among Bose's teachers at Cambridge were Lord Rayleigh, Michael Foster, James Dewar, Francis Darwin, Francis Balfour, Sidney Vines. At the time when Bose was a student at Cambridge, Prafulla Chandra Roy was a student at Edinburgh, they became intimate friends. He was married to Abala Bose, the renowned feminist and social worker. One of the important influence on Bose was Sister Nivedita who supported him by organizing the financial support and editing his manuscripts, she made sure that Bose was able to continue with and share his work; the Scottish theoretical physicist James Clerk Maxwell mathematically predicted the existence of electromagnetic radiation of diverse wavelengths, but he died in 1879 before his prediction was experimentally verified.
Between 1886 and 1888, Ger