The history of telecommunication began with the use of smoke signals and drums in Africa, the Americas and parts of Asia. In the 1790s, the first fixed semaphore systems emerged in Europe; however it was not until the 1830s that electrical telecommunication systems started to appear. This article details the history of telecommunication and the individuals who helped make telecommunication systems what they are today. The history of telecommunication is an important part of the larger history of communication.
Early telecommunications included smoke signals and drums. Talking drums were used by natives in Africa, and smoke signals in North America and China. Contrary to what one might think, these systems were often used to do more than merely announce the presence of a military camp.
In Rabbinical Judaism a signal was given by means of kerchiefs or flags at intervals along the way back to the high priest to indicate the goat "for Azazel" had been pushed from the cliff.
Greek hydraulic semaphore systems were used as early as the 4th century BC. The hydraulic semaphores, which worked with water filled vessels and visual signals, functioned as optical telegraphs. However, they could only utilize a very limited range of pre-determined messages, and as with all such optical telegraphs could only be deployed during good visibility conditions.
During the Middle Ages, chains of beacons were commonly used on hilltops as a means of relaying a signal. Beacon chains suffered the drawback that they could only pass a single bit of information, so the meaning of the message such as "the enemy has been sighted" had to be agreed upon in advance. One notable instance of their use was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London that signaled the arrival of the Spanish warships.
French engineer Claude Chappe began working on visual telegraphy in 1790, using pairs of "clocks" whose hands pointed at different symbols. These did not prove quite viable at long distances, and Chappe revised his model to use two sets of jointed wooden beams. Operators moved the beams using cranks and wires. He built his first telegraph line between Lille and Paris, followed by a line from Strasbourg to Paris. In 1794, a Swedish engineer, Abraham Edelcrantz built a quite different system from Stockholm to Drottningholm. As opposed to Chappe's system which involved pulleys rotating beams of wood, Edelcrantz's system relied only upon shutters and was therefore faster.
However semaphore as a communication system suffered from the need for skilled operators and expensive towers often at intervals of only ten to thirty kilometres (six to nineteen miles). As a result, the last commercial line was abandoned in 1880.
An early experiment in electrical telegraphy was an 'electrochemical' telegraph created by the German physician, anatomist and inventor Samuel Thomas von Sömmerring in 1809, based on an earlier, less robust design of 1804 by Spanish polymath and scientist Francisco Salva Campillo. Both their designs employed multiple wires (up to 35) in order to visually represent almost all Latin letters and numerals. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmerring's design), with each of the telegraph receiver's wires immersed in a separate glass tube of acid. An electric current was sequentially applied by the sender through the various wires representing each digit of a message; at the recipient's end the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver's operator would visually observe the bubbles and could then record the transmitted message, albeit at a very low baud rate. The principal disadvantage to the system was its prohibitive cost, due to having to manufacture and string-up the multiple wire circuits it employed, as opposed to the single wire (with ground return) used by later telegraphs.
Charles Wheatstone and William Fothergill Cooke patented a five-needle, six-wire system, which entered commercial use in 1838. It used the deflection of needles to represent messages and started operating over twenty-one kilometres (thirteen miles) of the Great Western Railway on 9 April 1839. Both Wheatstone and Cooke viewed their device as "an improvement to the [existing] electromagnetic telegraph" not as a new device.
On the other side of the Atlantic Ocean, Samuel Morse developed a version of the electrical telegraph which he demonstrated on 2 September 1837. Alfred Vail saw this demonstration and joined Morse to develop the register—a telegraph terminal that integrated a logging device for recording messages to paper tape. This was demonstrated successfully over three miles (five kilometres) on 6 January 1838 and eventually over forty miles (sixty-four kilometres) between Washington, D.C. and Baltimore on 24 May 1844. The patented invention proved lucrative and by 1851 telegraph lines in the United States spanned over 20,000 miles (32,000 kilometres). Morse's most important technical contribution to this telegraph was the simple and highly efficient Morse Code, co-developed with Vail, which was an important advance over Wheatstone's more complicated and expensive system, and required just two wires. The communications efficiency of the Morse Code preceded that of the Huffman code in digital communications by over 100 years, but Morse and Vail developed the code purely empirically, with shorter codes for more frequent letters.
The submarine cable across the English Channel, wire coated in gutta percha, was laid in 1851. Transatlantic cables installed in 1857 and 1858 only operated for a few days or weeks (carried messages of greeting back and forth between James Buchanan and Queen Victoria) before they failed. The project to lay a replacement line was delayed for five years by the American Civil War. The first successful transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time.
The electric telephone was invented in the 1870s, based on earlier work with harmonic (multi-signal) telegraphs. The first commercial telephone services were set up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven, Connecticut in the US and London, England in the UK. Alexander Graham Bell held the master patent for the telephone that was needed for such services in both countries. All other patents for electric telephone devices and features flowed from this master patent. Credit for the invention of the electric telephone has been frequently disputed, and new controversies over the issue have arisen from time-to-time. As with other great inventions such as radio, television, the light bulb, and the digital computer, there were several inventors who did pioneering experimental work on voice transmission over a wire, who then improved on each other's ideas. However, the key innovators were Alexander Graham Bell and Gardiner Greene Hubbard, who created the first telephone company, the Bell Telephone Company in the United States, which later evolved into American Telephone & Telegraph (AT&T), at times the world's largest phone company.
Telephone technology grew quickly after the first commercial services emerged, with inter-city lines being built and telephone exchanges in every major city of the United States by the mid-1880s. The first transcontinental telephone call occurred on January 25, 1915. Despite this, transatlantic voice communication remained impossible for customers until January 7, 1927 when a connection was established using radio. However no cable connection existed until TAT-1 was inaugurated on September 25, 1956 providing 36 telephone circuits.
In 1880, Bell and co-inventor Charles Sumner Tainter conducted the world's first wireless telephone call via modulated lightbeams projected by photophones. The scientific principles of their invention would not be utilized for several decades, when they were first deployed in military and fiber-optic communications.
The first transatlantic telephone cable (which incorporated hundreds of electronic amplifiers) was not operational until 1956, only six years before the first commercial telecommunications satellite, Telstar, was launched into space.
Over several years starting in 1894, the Italian inventor Guglielmo Marconi worked on adapting the newly discovered phenomenon of radio waves to telecommunication, building the first wireless telegraphy system using them. In December 1901, he established wireless communication between St. John's, Newfoundland and Poldhu, Cornwall (England), earning him a Nobel Prize in Physics (which he shared with Karl Braun) in 1909. In 1900 Reginald Fessenden was able to wirelessly transmit a human voice.
In 1924, Japanese engineer Kenjiro Takayanagi began a research program on electronic television. In 1925, he demonstrated a CRT television with thermal electron emission. In 1926, he demonstrated a CRT television with 40-line resolution, the first working example of a fully electronic television receiver. In 1927, he increased the television resolution to 100 lines, which was unrivaled until 1931. In 1928, he was the first to transmit human faces in half-tones on television, influencing the later work of Vladimir K. Zworykin.
On March 25, 1925, Scottish inventor John Logie Baird publicly demonstrated the transmission of moving silhouette pictures at the London department store Selfridge's. Baird's system relied upon the fast-rotating Nipkow disk, and thus it became known as the mechanical television. In October 1925, Baird was successful in obtaining moving pictures with halftone shades, which were by most accounts the first true television pictures. This led to a public demonstration of the improved device on 26 January 1926 again at Selfridges. His invention formed the basis of semi-experimental broadcasts done by the British Broadcasting Corporation beginning September 30, 1929.
For most of the twentieth century televisions used the cathode ray tube (CRT) invented by Karl Braun. Such a television was produced by Philo Farnsworth, who demonstrated crude silhouette images to his family in Idaho on September 7, 1927. Farnsworth's device would compete with the concurrent work of Kalman Tihanyi and Vladimir Zworykin. Though the execution of the device was not yet what everyone hoped it could be, it earned Farnsworth a small production company. In 1934, he gave the first public demonstration of the television at Philadelphia's Franklin Institute and opened his own broadcasting station. Zworykin's camera, based on Tihanyi's Radioskop, which later would be known as the Iconoscope, had the backing of the influential Radio Corporation of America (RCA). In the United States, court action between Farnsworth and RCA would resolve in Farnsworth's favour. John Logie Baird switched from mechanical television and became a pioneer of colour television using cathode-ray tubes.
The development of videotelephony involved the historical development of several technologies which enabled 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 very 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, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, 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 by 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. Only in the late 20th century with the advent of powerful video codecs and high-speed broadband did it become a practical technology for regular use. With the rapid improvements and popularity of the Internet, it became widespread through the use of videoconferencing and webcams, which frequently utilize Internet telephony, and in business, where telepresence technology has helped reduce the need to travel.
The first U.S. satellite to relay communications was Project SCORE in 1958, which used a tape recorder to store and forward voice messages. It was used to send a Christmas greeting to the world from U.S. President Dwight D. Eisenhower. In 1960 NASA launched an Echo satellite; the 100-foot (30 m) aluminized PET film balloon served as a passive reflector for radio communications. Courier 1B, built by Philco, also launched in 1960, was the world's first active repeater satellite. Satellites these days are used for many applications such as GPS, television, internet and telephone.
Telstar was the first active, direct relay commercial communications satellite. Belonging to AT&T as part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post Office) to develop satellite communications, it was launched by NASA from Cape Canaveral on July 10, 1962, the first privately sponsored space launch. Relay 1 was launched on December 13, 1962, and became the first satellite to broadcast across the Pacific on November 22, 1963.
The first and historically most important application for communication satellites was in intercontinental long distance telephony. The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted a receiving satellite dish via a geostationary satellite in Earth orbit. Improvements in submarine communications cables, through the use of fiber-optics, caused some decline in the use of satellites for fixed telephony in the late 20th century, but they still exclusively service remote islands such as Ascension Island, Saint Helena, Diego Garcia, and Easter Island, where no submarine cables are in service. There are also some continents and some regions of countries where landline telecommunications are rare to nonexistent, for example Antarctica, plus large regions of Australia, South America, Africa, Northern Canada, China, Russia and Greenland.
After commercial long distance telephone service was established via communication satellites, a host of other commercial telecommunications were also adapted to similar satellites starting in 1979, including mobile satellite phones, satellite radio, satellite television and satellite Internet access. The earliest adaption for most such services occurred in the 1990s as the pricing for commercial satellite transponder channels continued to drop significantly.
Realization and demonstration, on October 29, 2001, of the first digital cinema transmission by satellite in Europe of a feature film by Bernard Pauchon, Alain Lorentz, Raymond Melwig and Philippe Binant.
On September 11, 1940, George Stibitz was able to transmit problems using teletype to his Complex Number Calculator in New York City and receive the computed results back at Dartmouth College in New Hampshire. This configuration of a centralized computer or mainframe with remote dumb terminals remained popular throughout the 1950s. However it was not until the 1960s that researchers started to investigate packet switching a technology that would allow chunks of data to be sent to different computers without first passing through a centralized mainframe. A four-node network emerged on December 5, 1969 between the University of California, Los Angeles, the Stanford Research Institute, the University of Utah and the University of California, Santa Barbara. This network would become ARPANET, which by 1981 would consist of 213 nodes. In June 1973, the first non-US node was added to the network belonging to Norway's NORSAR project. This was shortly followed by a node in London.
ARPANET's development centred on the Request for Comment process and on April 7, 1969, RFC 1 was published. This process is important because ARPANET would eventually merge with other networks to form the Internet and many of the protocols the Internet relies upon today were specified through this process. In September 1981, RFC 791 introduced the Internet Protocol v4 (IPv4) and RFC 793 introduced the Transmission Control Protocol (TCP) — thus creating the TCP/IP protocol that much of the Internet relies upon today. A more relaxed transport protocol that, unlike TCP, did not guarantee the orderly delivery of packets called the User Datagram Protocol (UDP) was submitted on 28 August 1980 as RFC 768. An e-mail protocol, SMTP, was introduced in August 1982 by RFC 821 and http://1.0 a protocol that would make the hyperlinked Internet possible was introduced on May 1996 by RFC 1945.
However, not all important developments were made through the Request for Comment process. Two popular link protocols for local area networks (LANs) also appeared in the 1970s. A patent for the Token Ring protocol was filed by Olof Söderblom on October 29, 1974. And a paper on the Ethernet protocol was published by Robert Metcalfe and David Boggs in the July 1976 issue of Communications of the ACM. The Ethernet protocol had been inspired by the ALOHAnet protocol which had been developed by electrical engineering researchers at the University of Hawaii.
Internet access became widespread late in the century, using the old telephone and television networks.
Antonio Pérez Yuste (21 June 1968, Toledo, Spain) is a professor of Telecommunications Engineering at Technical University of Madrid, Spain (Spanish: Universidad Politécnica de Madrid, UPM). He is a senior member of the Institute of Electrical and Electronics Engineers (IEEE), an appointed member to the IEEE Spain Section Executive Committee, and an appointed member to the IEEE History Committee.Birth of public radio broadcasting
The birth of public radio broadcasting is credited to Lee de Forest who transmitted the world’s first public broadcast in New York City on January 13, 1910. This broadcast featured the voices of Enrico Caruso and other Metropolitan Opera stars. Members of the public and the press used earphones to listen to the broadcast in several locations throughout the city. This marked the beginning of what would become nearly universal wireless radio communication.Communications satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. There are 2,134 communications satellites in Earth’s orbit, used by both private and government organizations. Many are in geostationary orbit 22,200 miles (35,700 km) above the equator, so that the satellite appears stationary at the same point in the sky, so the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track it.
The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications satellites is to relay the signal around the curve of the Earth allowing communication between widely separated geographical points. Communications satellites use a wide range of radio and microwave frequencies. To avoid signal interference, international organizations have regulations for which frequency ranges or "bands" certain organizations are allowed to use. This allocation of bands minimizes the risk of signal interference.George P. Oslin
George P. Oslin (1899 — October 24, 1996) was an American reporter, executive at Western Union and author on the history of telecommunication.
Oslin graduated from Mercer University and the Graduate School of Journalism at Columbia University. He was a reporter for the Newark Star-Ledger and the Newark Evening News. As a reporter, he covered the Lindbergh kidnapping and the Hindenburg disaster. He was public relations director for Western Union, where he invented the singing telegram in 1933. At Oslin's suggestion, the first singing telegram was delivered to singer Rudy Vallee on July 28, 1933 for his birthday. While Oslin created the singing telegram because he thought "that messages should be fun," he recalled that he "was angrily informed I was making a laughingstock of the company."In his position at Western Union, he gathered the information that led him to write The Story of Telecommunications, (1992, reprinted 1999, ISBN 0-86554-659-2), which included the experiences of Thomas A. Edison, Ezra Cornell and other pioneers and was based on an extensive review of company documents, period newspapers, letters and diaries. He also wrote One Man's Century: From the Deep South to the Top of the Big Apple, (ISBN 0-86554-647-9) a memoir, published in December 1998.Global network
A global network is any communication network which spans the entire Earth. The term, as used in this article refers in a more restricted way to bidirectional communication networks, and to technology-based networks. Early networks such as international mail and unidirectional communication networks, such as radio and television, are described elsewhere.
The first global network was established using electrical telegraphy and global span was achieved in 1899. The telephony network was the second to achieve global status, in the 1950s. More recently, interconnected IP networks (principally the Internet, with estimated 2.5 billion users worldwide in 2014 ), and the GSM mobile communication network (with over 6 billion worldwide users in 2014) form the largest global networks of all.
Setting up global networks requires immensely costly and lengthy efforts lasting for decades. Elaborate interconnections, switching and routing devices, laying out physical carriers of information, such as land and submarine cables and earth stations must be set in operation. In addition, international communication protocols, legislation and agreements are involved.
Global networks might also refer to networks of individuals (such as scientists), communities (such as cities) and organizations (such as civil organizations) worldwide which, for instance, might have formed for the management, mitigation and resolval of global issues.History of broadcasting
It is generally recognised that the first radio transmission was made from a temporary station set up by Guglielmo Marconi in 1895. This followed on from pioneering work in the field by a number of people including Alessandro Volta, André-Marie Ampère, Georg Ohm and James Clerk Maxwell.The radio broadcasting of music and talk intended to reach a dispersed audience started experimentally around 1905-1906, and commercially around 1920 to 1923. VHF (very high frequency) stations started 30 to 35 years later.
In the early days, radio stations broadcast on the long wave, medium wave and short wave bands, and later on VHF (very high frequency) and UHF (ultra high frequency). However, in the United Kingdom, Hungary, France and some other places, from as early as 1890 there was already a system whereby news, music, live theatre, music hall, fiction readings, religious broadcasts, etc., were available in private homes [and other places] via the conventional telephone line, with subscribers being supplied with a number of special, personalised headsets. In Britain this system was known as Electrophone, and was available as early as 1895 or 1899 [sources vary] and up until 1926. In Hungary, it was called Telefon Hírmondó [1893-1920s], and in France, Théâtrophone [1890-1932]). The Wikipedia Telefon Hírmondó page includes a 1907 program guide which looks remarkably similar to the types of schedules used by many broadcasting stations some 20 or 30 years later.
By the 1950s, virtually every country had a broadcasting system, typically one owned and operated by the government. Alternative modes included commercial radio, as in the United States; or a dual system with both state sponsored and commercial stations, introduced in Australia as early as 1924, with Canada following in 1932. Today, most countries have evolved into a dual system, including the UK. By 1955, practically every family in North America and Western Europe, as well as Japan, had a radio. A dramatic change came in the 1960s with the introduction of small inexpensive portable transistor radio, the greatly expanded ownership and usage. Access became practically universal across the world.History of radio
The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed theory and inventions in what became radio. Radio development began as "wireless telegraphy". Later radio history increasingly involves matters of broadcasting.History of television
The invention of the television was the work of many individuals in the late 19th century and early 20th century. Individuals and corporations competed in various parts of the world to deliver a device that superseded previous technology. Many were compelled to capitalize on the invention and make profit, while some wanted to change the world through visual and audio communication technology.History of the telephone
This history of the telephone chronicles the development of the electrical telephone, and includes a brief review of its predecessors.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 very 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, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, 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. Very expensive videoconferencing systems rapidly evolved throughout the 1980s and 1990s from proprietary equipment, software and network requirements to standards-based technologies that were readily 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, business and commerce, telepresence technology, an advanced form of videoconferencing, has helped reduce the need to travel.Oslin
Oslin may refer to:
George P. Oslin (1899–1996), reporter, executive at Western Union and author on the history of telecommunication
K. T. Oslin (born 1942), American country music singer and songwriter
Sidney Oslin Smith Jr. (born 1923), former United States federal judgeOutline of telecommunication
The following outline is provided as an overview of and topical guide to telecommunication:
Telecommunication – the transmission of signals over a distance for the purpose of communication. In modern times, this process almost always involves the use of electromagnetic waves by transmitters and receivers, but in earlier years it also involved the use of drums and visual signals such as smoke, fire, beacons, semaphore lines and other optical communications.Photophone
The photophone is a telecommunications device that allows transmission of speech on a beam of light. It was invented jointly by Alexander Graham Bell and his assistant Charles Sumner Tainter on February 19, 1880, at Bell's laboratory at 1325 L Street in Washington, D.C. Both were later to become full associates in the Volta Laboratory Association, created and financed by Bell.
On June 3, 1880, Bell's assistant transmitted a wireless voice telephone message from the roof of the Franklin School to the window of Bell's laboratory, some 213 meters (about 700 ft.) away.Bell believed the photophone was his most important invention. Of the 18 patents granted in Bell's name alone, and the 12 he shared with his collaborators, four were for the photophone, which Bell referred to as his "greatest achievement", telling a reporter shortly before his death that the photophone was "the greatest invention [I have] ever made, greater than the telephone".The photophone was a precursor to the fiber-optic communication systems that achieved worldwide popular usage starting in the 1980s. The master patent for the photophone (U.S. Patent 235,199 Apparatus for Signalling and Communicating, called Photophone) was issued in December 1880, many decades before its principles came to have practical applications.Samsung Telecommunications
Samsung Mobile Division is one of five divisions within Samsung Electronics, belonging to the Samsung Group, and consists of the Mobile Communications Division, Telecommunication Systems Division, Computer Division, MP3 Business Team, Mobile Solution Centre and Telecommunication R&D Centre. Telecommunication Business produces a full spectrum of products from mobiles and other mobile devices such as MP3 players and laptop computers to telecommunication network infrastructure. Headquarters is located in Suwon, South Korea.
In 2007 Samsung Mobile Division Business reported over 40% growth and became the second largest mobile device manufacturer in the world. Its market share was 14% in Q4 2007, growing up form 11.3% in Q4 2006. At the end of November 2011, Samsung sold more than 300 million mobile devices which was a close second after Nokia with 300.6 million mobile devices sold in the first three quarter of 2011. As of Q3 2012, Samsung is the largest manufacturer of devices running Google Android with a 46% market share.
On 19 August 2016, Samsung officially released its Samsung Galaxy Note 7. As of 2 September 2016, Samsung announced a voluntary recall and attached to the new exchange program, after numerous of report showed that the new Samsung Galaxy Note 7 burst and exploded. On 10 October 2016, in response to the new incidents, Samsung announced that it would once again suspend sales of the Galaxy Note 7 and recall all devices worldwide. The next day, Samsung also announced that it would permanently discontinue the Galaxy Note 7 and cease its production.
As of October 7, comments have emerged from former CSPC experts following its launch of the investigation into the above incident.The lawsuit, filed in the US district court in California, suggests that the tech malfunctions extend beyond the Galaxy Note 7 and that Samsung “chose to conceal the problem from the public despite knowing the foreseeable and predictable risk that the phone may overheat, flame and destruct from the inside presenting a risk of serious harm or injury”.
The recall had a major impact on Samsung's business in the third quarter of 2016, with the company projecting that its operating profits would be down by 33% in comparison to the previous quarter. Credit Suisse analysts estimated that Samsung would lose at least US$17 billion in revenue from the production and recall of the Galaxy Note 7.Semaphore telegraph
A semaphore telegraph is an early system of conveying information by means of visual signals, using towers with pivoting shutters, also known as blades or paddles. Information is encoded by the position of the mechanical elements; it is read when the shutter is in a fixed position. The most widely used system was invented in 1792 in France by Claude Chappe, and was popular in the late eighteenth to early nineteenth centuries. Lines of relay towers with a semaphore rig at the top were built within line-of-sight of each other, at separations of 5–20 miles (8.0–32.2 km). Operators at each tower would watch the neighboring tower through a spyglass, and when the semaphore arms began to move spelling out a message, they would pass the message on to the next tower. This system was much faster than post riders for conveying a message over long distances, and also had cheaper long-term operating costs, once constructed. Semaphore lines were a precursor of the electrical telegraph, which would replace them half a century later, and would also be cheaper, faster, and more private. The line-of-sight distance between relay stations was limited by geography and weather, and prevented the optical telegraph from crossing wide expanses of water, unless a convenient island could be used for a relay station. Modern derivatives of the semaphore system include flag semaphore (a flag relay system) and the heliograph (optical telegraphy using mirror-directed sunlight reflections).Telecommunications engineering
Telecommunications engineering is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems. The work ranges from basic circuit design to strategic mass developments. A telecommunication engineer is responsible for designing and overseeing the installation of telecommunications equipment and facilities, such as complex electronic switching systems, and other plain old telephone service facilities, optical fiber cabling, IP networks, and microwave transmission systems. Telecommunication engineering also overlaps with broadcast engineering.
Telecommunication is a diverse field of engineering connected to electronic, civil and systems engineering. they help find the cost of money for different types of computers and technological objects. Ultimately, telecom engineers are responsible for providing high-speed data transmission services. They use a variety of equipment and transport media to design the telecom network infrastructure; the most common media used by wired telecommunications today are twisted pair, coaxial cables, and optical fibers. Telecommunications engineers also provide solutions revolving around wireless modes of communication and information transfer, such as wireless telephony services, radio and satellite communications, and internet and broadband technologies.Telephone exchange
A telephone exchange is a telecommunications system used in the public switched telephone network or in large enterprises. An exchange consists of electronic components and in older systems also human operators that interconnect (switch) telephone subscriber lines or virtual circuits of digital systems to establish telephone calls between subscribers.
In historical perspective, telecommunication terms have been used with different semantics over time. The term telephone exchange is often used synonymously with central office (CO), a Bell System term. Often, a central office is defined as a building used to house the inside plant equipment of potentially several telephone exchanges, each serving a certain geographical area. Such an area has also been referred to as the exchange. Central office locations may also be identified in North America as wire centers, designating a facility from which a telephone obtains dial tone. For business and billing purposes, telephony carriers also define rate centers, which in larger cities may be clusters of central offices, to define specified geographical locations for determining distance measurements.
In the United States and Canada, the Bell System established in the 1940s a uniform system of identifying central offices with a three-digit central office code, that was used as a prefix to subscriber telephone numbers. All central offices within a larger region, typically aggregated by state, were assigned a common numbering plan area code. With the development of international and transoceanic telephone trunks, especially driven by direct customer dialing, similar efforts of systematic organization of the telephone networks occurred in many countries in the mid-20th century.
For corporate or enterprise use, a private telephone exchange is often referred to as a private branch exchange (PBX), when it has connections to the public switched telephone network. A PBX is installed in enterprise facilities, typically collocated with large office spaces or within an organizational campus to serve the local private telephone system and any private leased line circuits. Smaller installations might deploy a PBX or key telephone system in the office of a receptionist.Universal Service Fund
The Universal Service Fund (USF) is a system of telecommunications subsidies and fees managed by the United States Federal Communications Commission (FCC) intended to promote universal access to telecommunications services in the United States. The FCC established the fund in 1997 in compliance with the Telecommunications Act of 1996. The FCC is a government agency that implements and enforces America's communication regulations in all 50 states, the District of Columbia, and other U.S. territories. The fund reported a total of $7.82 billion in disbursements in 2014, divided among its four programs. The fund is supported by charging telecommunications companies a fee which is set quarterly. As of the fourth quarter of 2018, the rate is 20.1% of a telecom company's interstate and international end-user revenues.While separate itemization is not required by the FCC, it is common for USF fees to be listed separately from other charges on a consumer's bill. Universal Service charges should not be confused with what are sometimes referred to in telephone company bills as "Federal Subscriber Line" charges, which are access fees charged by telecommunications companies, not the local or federal government.Some have raised concerns about the future funding of the USF; despite falling taxable revenues, the size of the fund has increased from $1.2 billion in collections at 5.7% in 4Q 2000, to $2.2 billion in 4Q 2014 at 16.1%. Some believe that reclassifying broadband Internet access services under Title II of the 1996 Telecommunications Act would be followed by requiring ISPs to pay into the USF as a new source of revenue for the fund. But the FCC has made clear that it will not require contributions on broadband Internet access revenues at this time, as the FCC will forbear from the contribution requirements in Section 254(d) of the Communications Act.