Texas Flip N Move - Wikipedia

 Texas Flip N Move

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 Texas Flip N Move

 Genre

 Reality television

 Country of origin

 United States

 Original language ( s )

 English

 Production

 Running time

 40 minutes

 Release

 Original network

 DIY Network

 Original release

 November 11 , 2014 ( 2014 - 11 - 11 ) -- present

 External links

 Website

 texasflipnmove. build

 Texas Flip N Move is a show featured on DIY Network .

 Contents

 ( hide )

 1 Premise

 1.1 Cast

 2 Series overview

 3 See also

 4 References

 5 External links

 Premise ( edit )

 The show features professional home renovators who purchase older houses to flip for profit .

 However , unlike Property Brothers or other similar shows , the show features a twist : at the auction , only the houses are sold ( not the underlying land ) . The bidders can only view the home from the outside and must also factor in costs of moving the house from the original lot to the renovation site ( another facility where the houses are renovated and later sold at auction to purchasers wanting houses to move to existing property ) .

 Cast ( edit )

 Donna Snow Landers and Toni Snow Barksdale ( `` The Snow Sisters '' ) ( Season 1 - present )

 Randy Martin ( `` The Lone Wolf '' ) ( Season 1 - present )

 Myers Jackson ( the selling auctioneer ) ( Season 1 - present )

 Casey Hester and Catrina Kidd ( Seasons 4 - present )

 From Season 1 to Season 3 , Casey was Cody 's cousin and moved houses for the Young Guns . From Season 3 he moves and flips house with the Young Guns at season 3 and with Catrina from Season 4 . Casey and Catrina are not married to each other .

 `` Gary 's Girls '' ( Season 4 - present )

 Gary Snow is the brother of Donna and Toni ; his four daughters ( Donna and Toni 's nieces ) were featured in a Season 3 episode where they and the Snow Sisters each renovated a shipping contain

 Paige and Raf . ( Seasons 6 - present )

 Gary and Jerry ( Seasons 7 - present )

 Cody Biffel ( Foreman )

 Cody and Suzi Slay ( `` The Young Guns '' ) ( Seasons 1 - 3 )

 H.D. `` Daddy '' Snow ( occasional appearances )

 Daddy Snow is the father of Donna , Gary , and Toni , and the grandfather of Gary 's four daughters . In his 80 's , he is still active in the house - moving business . He inherited a company created by his father C.A. Snow .

 Series overview ( edit )

 Main article : List of Texas Flip N Move episodes

 Season

 Episodes

 Originally aired

 Season premiere

 Season finale

 9

 November 11 , 2014

 March 6 , 2015

 13

 September 18 , 2015

 December 11 , 2015

 13

 January 8 , 2016

 April 1 , 2016

 13

 July 15 , 2016

 October 7 , 2016

 5

 13

 November 25 , 2016

 March 3 , 2017

 6

 13

 April 7 , 2017

 June 30 , 2017

 7

 13

 October 6 , 2017

 See also ( edit )

 Louisiana Flip and Move

 References ( edit )

 Jump up ^ `` Texas Flip and Move '' .

 ^ Jump up to : `` Texas Flip N Move '' . Zap2it .

 External links ( edit )

 Official Website

 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Texas_Flip_N_Move&oldid=815134751 '' Categories :

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 2010 American television series debuts

 English - language television programs

 Home renovation television series

 Television shows set in Texas

 Fort Worth , Texas

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 This page was last edited on 12 December 2017 , at 23 : 32 .

 About Wikipedia

Question: texas flip and move how does it work


Economy of the Ming dynasty - wikipedia

 Economy of the Ming dynasty

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 This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . ( October 2010 ) ( Learn how and when to remove this template message )

 The Ming Empire around 1580

 The economy of the Ming dynasty ( 1368 -- 1644 ) of China was the largest in the world during that period . It is regarded as one of China 's three golden ages ( the other two being the Han and Song periods ) . The period was marked by the increasing political influence of the merchants , the gradual weakening of imperial rule , and technological advances .

 Contents

 ( hide )

 1 Currency

 2 Manufactures

 2.1 Privatization

 2.2 Emergence of wage labor

 3 Early encouragement of agriculture under Hongwu

 3.1 Emergence of commercial plantations

 3.2 Rural markets during the Ming

 4 Trade and investment

 4.1 Taxation

 4.2 Weakening of the state

 4.3 Sprouts of capitalism

 5 See also

 6 References

 7 External links

 Currency ( edit )

 Further information : Ming dynasty coinage

 The early Ming dynasty attempted to use paper currency , with outflows of bullion limited by its ban on private foreign commerce . Like its forebears , the currency experienced massive counterfeiting and hyperinflation . ( In 1425 , Ming notes were trading at about 0.014 % of its original value under the Hongwu Emperor . ) The notes remained in circulation as late as 1573 but their printing was ended in 1450 . Minor coins were minted in base metals , but trade mostly occurred using silver ingots . As their purity and exact weight varied , they were treated as bullion and measured in tael . These privately made `` sycee '' first came into use in Guangdong , spreading to the lower Yangtze sometime before 1423 , the year it became acceptable for payment of tax obligations . In the mid-15th century , the paucity of circulating silver caused a monetary contraction and extensive reversion to barter . The problem was met through smuggled , then legal , importation of Japanese silver ( mostly through the Portuguese and Dutch ) and Spanish silver from Potosí carried on the Manila galleons . Provincial taxes were required to be paid in silver in 1465 ; the salt tax , in 1475 ; and corvée exemptions , in 1485 . By the late Ming , the amount of silver being used was extraordinary : at a time when English traders considered tens of thousands of pounds an exceptional fortune , the Zheng clan of merchants regularly engaged in transactions valued at millions of taels . However , a second silver contraction occurred in the mid-17th century when King Philip IV began enforcing laws limiting direct trade between Spanish South America and China at about the same time the new Tokugawa shogunate in Japan restricted most of its foreign exports , cutting off Dutch and Portuguese access to its silver . The dramatic spike in silver 's value in China made payment of taxes nearly impossible for most provinces . In extremis , the government even resumed use of paper currency amid Li Zicheng 's rebellion .

 Manufactures ( edit )

 Privatization ( edit )

 Another key feature of the Ming manufacturing industry was privatization . Unlike the Song , in which state - owned enterprises played a large role , the Ming reverted to the old laissez faire policies of the Han by privatizing the salt and tea industries . By the middle of the Ming dynasty , powerful groups of wealthy merchants had replaced the state as the dominant movers behind Chinese industry .

 Emergence of wage labor ( edit )

 The Ming government abolished the mandatory forced labor by peasants used in early dynasties and replaced it with wage labor . A new class of wage laborers sprung up where none had existed before . In Jingde alone , it was reported that there were no less than 300 pottery factories , all operated by wage laborers .

 Early encouragement of agriculture under Hongwu ( edit )

 In order to recover from rule of the Mongols and the wars that followed them , the Hongwu Emperor enacted pro-agricultural policies . The state invested extensively in agricultural canals , reduced taxes on agriculture to 1 / 30 of the output , and later to 1.5 % of agricultural output . Ming farmers also introduced many innovations such as water - powered plows , and new agricultural methods such as crop rotation . This led to a massive agricultural surplus that became the basis of a market economy .

 Emergence of commercial plantations ( edit )

 The Ming saw the rise of commercial plantations who produced crops suitable to their regions . Tea , fruits , paint and other goods were produced on a massive scale by these agricultural plantations . Regional patterns of production established during this period continued into the Qing dynasty . The Columbian exchange brought crops such as corn with these foreign crops . During the Ming , specialized areas also popped up planting large numbers of cash crops that could be sold at markets . Large numbers of peasants abandoned the land to become artisans . The population of the Ming boomed ; estimates for the population of the Ming range from 160 to 200 million .

 Rural markets during the Ming ( edit )

 Ming agriculture was much changed from the earlier areas ; firstly , gigantic areas , devoting and specializing in cash crops , sprung up to demand from the new market economy . Secondly , agricultural tools and carts , some water - powered , help to create a gigantic agricultural surplus which formed the basis of the rural economy . Besides rice , other crops were grown on a large scale .

 Although images of autarkic farmers who had no connection to the rest of China may have some merit for the earlier Han and T'ang dynasties , this was certainly not the case for the Ming dynasty . During the Ming dynasty , the increase in population and the decrease in quality land made it necessary that farmers make a living off cash crops . Many of these markets appeared in the rural countryside , where goods were exchanged and bartered .

 A second type of market that developed in China was the urban - rural type , in which rural goods were sold to urban dwellers . This was particular the case when landlords decided to reside in the cities , and use income coming from rural land holding to facilitate exchange in the cities . Another way this type of market was used was professional merchants who bought rural goods in large quantities .

 The third type of market was the `` national market '' which was developed during the Song dynasty but particularly enhanced during the Ming . This market involved not only the exchange described above , but also products produced directly for the market . Unlike earlier dynasties , many Ming peasants were no longer producing only products they needed ; many of them produced products for the market , which then they sold at a profit .

 Trade and investment ( edit )

 Main article : Haijin

 In the early Ming , after the devastation of the war which expelled the Mongols , the Hongwu Emperor imposed severe restrictions on trade ( the `` haijin '' ) . Believing that agriculture was the basis of the economy , Hongwu favored that industry over all else , including that of merchants . After his death , most of his policies were reversed by his successors . By the late Ming , the state was losing power to the very merchants which Hongwu had wanted to restrict .

 The Ming dynasty also engaged in a thriving trade with both Europe and Japan . The amount of silver flowing into the Ming dynasty was estimated by Joseph Needham at 300 million taels , which is equivalent to more than 190 billion dollars in today 's money . In addition to silver , the Ming also imported many European firearms , in order to ensure the modernness of their weapons .

 Trade and commerce thrived in this liberalized economy , and was aided by the construction of canals , roads , and bridges by the Ming government . The Ming saw the rise of several merchant clans such as the Huai and Jin clans , who disposed of large amounts of wealth . The gentry and merchant classes started to fuse , and the merchants gained power at the expense of the state . Some merchants were reputed to have a treasure of 30 million taels .

 Taxation ( edit )

 Ming taxation was light . Taxes on agriculture were only 1 / 30 of agricultural produce , and were later reduced to 1 / 50 of produce . Taxes on commerce amounted to 1 / 30 of commerce also , but was later reduced to 1.5 % . These low taxes spurred trade , but severely weakened the state . Salt , as in earlier dynasties , was an important source of state revenue , but required constant and competent management . With the coming of the Little Ice Age in the 17th century , the state 's low revenues and its inability to raise taxes caused massive deficits , and large numbers of Ming troops defected or rebelled because they had not been paid .

 Weakening of the state ( edit )

 During the Ming , the controls imposed on the economy were gradually relaxed . State monopolies on salt and iron ended as these and other industries were privatized . Taxes were reduced from the high levels under the Mongol Yuan , and the Ming had one of the lowest tax rates ( per person ) in the world . The entire foreign trade , which was estimated at up to 300 million taels , provided the Ming with a tax of only about 40,000 taels a year . When the Wanli Emperor sought to increase the salt tax , his measures were opposed by violence and the eunuchs he sent to collect the tax were beheaded by local officials .

 Sprouts of capitalism ( edit )

 Investment and capital moved off the land and were poured into ventures . Continuing the trend from the Song , Ming investors poured large amounts of capital into ventures and reaped high profits . Many Chinese scholars believe the Ming was the dynasty in which the `` sprouts of capitalism '' emerged in China , only to be suppressed by the Qing Dynastry . This theory was widely promoted by Communist scholars during the Maoist period , and suffers from that period 's general condemnation of the Manchu Qing , who were accused of mis - managing the Chinese state in the face of foreign encroachment .

 See also ( edit )

 Economic history of China

 Economy of the Han dynasty

 Economy of the Song dynasty

 References ( edit )

 Jump up ^ Von Glahn , Richard ( 1996 ) , Fountain of Fortune : Money and Monetary Policy in China , 1000 -- 1700 , Berkeley : University of California Press , pp. 90 -- 1 , ISBN 0 - 520 - 20408 - 5 .

 Jump up ^ Fairbank , John K. ; et al. ( 2006 ) , China : A New History ( 2nd ed . ) , Cambridge : Harvard University Press , p. 134 , ISBN 0 - 674 - 01828 - 1 .

 Jump up ^ Atwell , William S. ( 1998 ) , `` Ming China and the Emerging World Economy , c. 1470 -- 1650 '' , The Cambridge History of China , Vol. 8 : The Ming Dynasty : 1368 -- 1644 , Cambridge : Cambridge University Press , p. 387 , ISBN 0521243335 .

 Jump up ^ Brook , Timothy ( 1998 ) , The Confusions of Pleasure : Commerce and Culture in Ming China , Berkeley : University of California Press , p. 208 , ISBN 0 - 520 - 22154 - 0 .

 ^ Jump up to : Li Bo , Zheng Yin , `` 5000 years of Chinese history '' , Inner Mongolian People 's publishing corp , 2001 , ISBN 7 - 204 - 04420 - 7 , pp. 994 -- 997 .

 ^ Jump up to : Twitchett , Denis ; John K. Fairbank . the Ming dynasty part 2 ( May 1987 ) , The Cambridge History of China , ISBN 978 - 0 - 521 - 24327 - 8 , pp. 497 -- 498 .

 Jump up ^ Huang , Ray ( 1998 ) , `` The Ming fiscal administration '' , in Twitchett , Denis and Fairbank , John K. ( eds . ) , The Ming Dynasty , 1 398 -- 1644 , Part 2 , The Cambridge History of China , 8 , Cambridge : Cambridge University Press , pp. 106 -- 172 , ISBN 978 - 0 - 521 - 24333 - 9 CS1 maint : Uses editors parameter ( link )

 External links ( edit )

 China 's GDP in the Ming Dynasty Guan Hanhui David Daokui Li

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Question: global trade during the ming dynasty of china


Shortwave radio - wikipedia

 Shortwave radio

 Jump to : navigation , search `` Shortwave '' redirects here . For other uses , see Shortwave ( disambiguation ) . Grundig Satellit 400 solid - state , digital shortwave receiver , circa 1986

 Shortwave radio is radio transmission using shortwave radio frequencies . There is no official definition of the band , but the range always includes all of the high frequency band ( HF ) , and generally extends from 1.7 -- 30 MHz ( 176.3 -- 10.0 m ) ; from the high end of the medium frequency band ( MF ) just above the mediumwave AM broadcast band , to the end of the HF band .

 Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere . Therefore , short waves directed at an angle into the sky can be reflected back to Earth at great distances , beyond the horizon . This is called skywave or `` skip '' propagation . Thus shortwave radio can be used for very long distance communication , in contrast to radio waves of higher frequency which travel in straight lines ( line - of - sight propagation ) and are limited by the visual horizon , about 40 miles ( 64 km ) . Shortwave radio is used for broadcasting of voice and music to shortwave listeners over very large areas ; sometimes entire continents or beyond . It is also used for military over-the - horizon radar , diplomatic communication , and two - way international communication by amateur radio enthusiasts for hobby , educational and emergency purposes , as well as for long distance aviation and marine communications .

 Contents

 ( hide )

 1 Frequency classifications

 2 History

 2.1 Development

 2.2 Amateur use of shortwave propagation

 3 Propagation characteristics

 4 Types of modulation

 5 Users

 6 Shortwave broadcasting

 6.1 Frequency allocations

 6.2 Advantages

 6.3 Disadvantages

 7 Shortwave listening

 8 Shortwave broadcasts and music

 9 Shortwave 's future

 10 See also

 11 References

 12 External links

 Frequency classifications ( edit )

 The widest popular definition of the shortwave frequency interval is the ITU Region 1 ( EU + Africa + Russia ... ) definition , and is the span 1.6 -- 30 MHz , just above the medium wave band , which ends approximately at 1.6 MHz .

 There are also other definitions of the shortwave frequency interval :

 1.71 to 30 MHz in ITU Region 2 ( North and South America ... )

 1.8 ( 160 meter radio amateur band start ) to 30 MHz

 2.3 ( 120 meter band start ) to 30 MHz

 2.3 ( 120 meter band start ) to 26.1 MHz ( 11 meter band end )

 In Germany and perhaps Austria the ITU Region 1 shortwave radio frequency interval can be subdivided in :

 de : Grenzwelle ( `` border waves '' ) : 1.605 -- 3.8 MHz

 In Germany these shortwave radio frequency intervals have also been seen used :

 the above other definitions

 History ( edit )

 Development ( edit )

 Radio amateurs carried out the first shortwave transmissions over a long distance before Guglielmo Marconi

 The name `` shortwave '' originated during the early days of radio in the early 20th century , when the radio spectrum was considered divided into long wave ( LW ) , medium wave ( MW ) and short wave bands based on the wavelength of the radio waves . Shortwave radio received its name because the wavelengths in this band are relatively shorter than 200 m ( 1,500 kHz ) which marked the original upper limit of the medium frequency band first used for radio communications . The broadcast medium wave band now extends above the 200 m / 1,500 kHz limit , and the amateur radio 1.8 MHz -- 2.0 MHz band ( known as the `` top band '' ) is the lowest - frequency band considered to be ' shortwave ' .

 Early long distance radio telegraphy used long waves , below 300 kilohertz ( kHz ) . The drawbacks to this system included a very limited spectrum available for long distance communication , and the very expensive transmitters , receivers and gigantic antennas that were required . It was also difficult to beam the radio wave directionally with long wave , resulting in a major loss of power over long distances . Prior to the 1920s , the shortwave frequencies above 1.5 MHz were regarded as useless for long distance communication and were designated in many countries for amateur use .

 Guglielmo Marconi , pioneer of radio , commissioned his assistant Charles Samuel Franklin to carry out a large scale study into the transmission characteristics of short wavelength waves and to determine their suitability for long distance transmissions . Franklin rigged up a large antenna at Poldhu Wireless Station , Cornwall , running on 25 kW of power . In June and July 1923 , wireless transmissions were completed during nights on 97 meters from Poldhu to Marconi 's yacht Elettra in the Cape Verde Islands .

 In September 1924 , Marconi transmitted daytime and nighttime on 32 meters from Poldhu to his yacht in Beirut . Franklin went on to refine the directional transmission , by inventing the curtain array aerial system . In July 1924 , Marconi entered into contracts with the British General Post Office ( GPO ) to install high speed shortwave telegraphy circuits from London to Australia , India , South Africa and Canada as the main element of the Imperial Wireless Chain . The UK - to - Canada shortwave `` Beam Wireless Service '' went into commercial operation on 25 October 1926 . Beam Wireless Services from the UK to Australia , South Africa and India went into service in 1927 .

 Shortwave communications began to grow rapidly in the 1920s , similar to the internet in the late 20th century . By 1928 , more than half of long distance communications had moved from transoceanic cables and longwave wireless services to shortwave and the overall volume of transoceanic shortwave communications had vastly increased . Shortwave stations had cost and efficiency advantages over massive longwave wireless installations , however some commercial longwave communications stations remained in use until the 1960s . Long distance radio circuits also reduced the load on the existing transoceanic telegraph cables and hence the need for new cables , although the cables maintained their advantages of high security and a much more reliable and better quality signal than shortwave .

 The cable companies began to lose large sums of money in 1927 , and a serious financial crisis threatened the viability of cable companies that were vital to strategic British interests . The British government convened the Imperial Wireless and Cable Conference in 1928 `` to examine the situation that had arisen as a result of the competition of Beam Wireless with the Cable Services '' . It recommended and received Government approval for all overseas cable and wireless resources of the Empire to be merged into one system controlled by a newly formed company in 1929 , Imperial and International Communications Ltd . The name of the company was changed to Cable and Wireless Ltd. in 1934 .

 Long - distance cables had a resurgence beginning in 1956 with the laying of TAT - 1 across the Atlantic Ocean , the first voice frequency cable on this route . This provided 36 high quality telephone channels and was soon followed by even higher capacity cables all around the world . These sounded the death knell of shortwave radio for commercial communications .

 Amateur use of shortwave propagation ( edit )

 Hallicrafters SX - 28 shortwave receiver analog tuning dial , circa 1944

 Amateur radio operators also discovered that long - distance communication was possible on shortwave bands . Early long - distance services used surface wave propagation at very low frequencies , which are attenuated along the path at wavelengths shorter than 1,000 meters . Longer distances and higher frequencies using this method meant more signal loss . This , and the difficulties of generating and detecting higher frequencies , made discovery of shortwave propagation difficult for commercial services .

 Radio amateurs may have conducted the first successful transatlantic tests in December 1921 , operating in the 200 meter mediumwave band ( near 1,500 kHz in the modern AM broadcast band ) -- the shortest wavelength then available to amateurs . In 1922 hundreds of North American amateurs were heard in Europe on 200 meters and at least 20 North American amateurs heard amateur signals from Europe . The first two - way communications between North American and Hawaiian amateurs began in 1922 at 200 meters . Although operation on wavelengths shorter than 200 meters was technically illegal ( but tolerated as the authorities mistakenly believed at first that such frequencies were useless for commercial or military use ) , amateurs began to experiment with those wavelengths using newly available vacuum tubes shortly after World War I .

 Extreme interference at the longer edge of the 150 -- 200 meter band -- the official wavelengths allocated to amateurs by the Second National Radio Conference in 1923 -- forced amateurs to shift to shorter and shorter wavelengths ; however , amateurs were limited by regulation to wavelengths longer than 150 meters ( 2 MHz ) . A few fortunate amateurs who obtained special permission for experimental communications at wavelengths shorter than 150 meters completed hundreds of long distance two way contacts on 100 meters ( 3 MHz ) in 1923 including the first transatlantic two way contacts .

 By 1924 many additional specially licensed amateurs were routinely making transoceanic contacts at distances of 6,000 miles ( 9,600 km ) and more . On 21 September 1924 several amateurs in California completed two - way contacts with an amateur in New Zealand . On 19 October amateurs in New Zealand and England completed a 90 minute two - way contact nearly halfway around the world . On 10 October the Third National Radio Conference made three shortwave bands available to U.S. amateurs at 80 meters ( 3.75 MHz ) , 40 meters ( 7 MHz ) and 20 meters ( 14 MHz ) . These were allocated worldwide , while the 10 meter band ( 28 MHz ) was created by the Washington International Radiotelegraph Conference on 25 November 1927 . The 15 meter band ( 21 MHz ) was opened to amateurs in the United States on 1 May 1952 .

 Propagation characteristics ( edit )

 Formation of a skip zone

 Shortwave radio frequency energy is capable of reaching any location on the Earth as it is influenced by ionospheric reflection back to the earth by the ionosphere , ( a phenomenon known as `` skywave propagation '' ) . A typical phenomenon of shortwave propagation is the occurrence of a skip zone where reception fails . With a fixed working frequency , large changes in ionospheric conditions may create skip zones at night .

 As a result of the multi-layer structure of the ionosphere , propagation often simultaneously occurs on different paths , scattered by the E or F region and with different numbers of hops , a phenomenon that may be disturbed for certain techniques . Particularly for lower frequencies of the shortwave band , absorption of radio frequency energy in the lowest ionospheric layer , the D layer , may impose a serious limit . This is due to collisions of electrons with neutral molecules , absorbing some of a radio frequency 's energy and converting it to heat . Predictions of skywave propagation depend on :

 The distance from the transmitter to the target receiver .

 Time of day . During the day , frequencies higher than approximately 12 MHz can travel longer distances than lower ones . At night , this property is reversed .

 With lower frequencies the dependence on the time of the day is mainly due to the lowest ionospheric layer , the D Layer , forming only during the day when photons from the sun break up atoms into ions and free electrons .

 Season . During the winter months of the Northern or Southern hemispheres , the AM / MW broadcast band tends to be more favorable because of longer hours of darkness .

 Solar flares produce a large increase in D region ionization so high , sometimes for periods of several minutes , all skywave propagation is nonexistent .

 Types of modulation ( edit )

 Further information : Modulation National Panasonic R3000 analog shortwave receiver , circa 1965

 Several different types of modulation are used to impress information on a short - wave transmission .

 Amplitude modulation is the simplest type and the most commonly used for shortwave broadcasting . The instantaneous amplitude of the carrier is controlled by the amplitude of the signal ( speech , or music , for example ) . At the receiver , a simple detector recovers the desired modulation signal from the carrier .

 Single sideband transmission is a form of amplitude modulation but in effect filters the result of modulation . An amplitude - modulated signal has frequency components both above and below the carrier frequency . If one set of these components is eliminated as well as the residual carrier , only the remaining set is transmitted . This reduces power in the transmission , as roughly 2 / 3 of the energy sent by an AM signal is unnecessary to recover the information contained on it . It also reduces `` bandwidth '' , enabling about one - half the carrier frequency spectrum width to be used . The drawback is the receiver is more complicated , since it must re-create the carrier to recover the signal . Small errors in the detection process greatly affect the pitch of the received signal . As a result , single sideband is not used for music or general broadcast . Single sideband is used for long - range voice communications by ships and aircraft , Citizen 's Band , and amateur radio operators . Lower sideband ( LSB ) is generally used below 9 MHz and USB ( upper sideband ) above 9 MHz .

 Vestigal sideband transmits the carrier and one complete sideband , but filters out the other sideband . It is a compromise between AM and SSB , enabing simple receivers to be used , but requires almost as much transmitter power as AM . One advantage is only half the bandwidth of an AM signal is used . It can be heard in the transmission of certain radio time signal stations . Vestigial sideband is used for over the air Television Broadcasts both analog and digital .

 Continuous wave ( CW ) is on - and - off keying of a carrier , used for Morse code communications and Hellschreiber facsimile - based teleprinter transmissions .

 Narrow - band frequency modulation ( NBFM ) is used typically above 20 MHz . Because of the larger bandwidth required , NBFM is commonly used for VHF communication . Regulations limit the bandwidth of a signal transmitted in the HF bands , and the advantages of frequency modulation are greatest if the FM signal has a wide bandwidth . NBFM is limited to short - range transmissions due to the multiphasic distortions created by the ionosphere .

 Digital Radio Mondiale ( DRM ) is a digital modulation for use on bands below 30 MHz .

 Radioteletype , fax , digital , slow - scan television and other systems use forms of frequency - shift keying or audio subcarriers on a shortwave carrier . These generally require special equipment to decode , such as software on a computer equipped with a sound card .

 Users ( edit )

 Portable shortwave receiver 's digital display tuned to the 75 meter band

 Some established users of the shortwave radio bands may include :

 International broadcasting primarily by government - sponsored propaganda , international news ( for example , the BBC World Service ) or cultural stations to foreign audiences : the most common use of all .

 Domestic broadcasting : to widely dispersed populations with few longwave , mediumwave and FM stations serving them ; or for specialty political , religious and alternative media networks ; or of individual commercial and non-commercial paid broadcasts .

 Oceanic air traffic control uses the HF / shortwave band for long distance communication to aircraft over the oceans and poles , which are far beyond the range of traditional VHF frequencies . Modern systems also include satellite communications , such as ADS - C / CPDLC

 `` Utility '' stations transmitting messages not intended for the general public , such as merchant shipping , marine weather , and ship - to - shore stations ; for aviation weather and air - to - ground communications ; for military communications ; for long - distance governmental purposes , and for other non-broadcast communications .

 Amateur radio operators at the 80 / 75 , 60 , 40 , 30 , 20 , 17 , 15 , 12 , and 10 - meter bands . Licenses are granted by authorized government agencies .

 Time signal and radio clock stations : In North America , WWV radio and WWVH radio transmit at these frequencies : 2.5 MHz , 5 MHz , 10 MHz , and 15 MHz ; and WWV also transmits on 20 MHz . The CHU radio station in Canada transmits on the following frequencies : 3.33 MHz , 7.85 MHz , and 14.67 MHz . Other similar radio clock stations transmit on various shortwave and longwave frequencies around the world . The shortwave transmissions are primarily intended for human reception , while the longwave stations are generally used for automatic synchronization of watches and clocks .

 Sporadic or non-traditional users of the shortwave bands may include :

 Clandestine stations . These are stations that broadcast on behalf of various political movements such as rebel or insurrectionist forces . They may advocate civil war , insurrection , rebellion against the government - in - charge of the country to which they are directed . Clandestine broadcasts may emanate from transmitters located in rebel - controlled territory or from outside the country entirely , using another country 's transmission facilities .

 Numbers Stations . These stations regularly appear and disappear all over the shortwave radio band but are unlicensed and untraceable . It is believed that Numbers Stations are operated by government agencies and are used to communicate with clandestine operatives working within foreign countries . However , no definitive proof of such use has emerged . Because the vast majority of these broadcasts contain nothing but the recitation of blocks of numbers , in various languages , with occasional bursts of music , they have become known colloquially as `` Number Stations '' . Perhaps the most noted Number Station is the `` Lincolnshire Poacher '' , named after the 18th century English folk song , which is transmitted just before the sequences of numbers .

 Unlicensed two way radio activity by individuals such as taxi drivers , bus drivers and fishermen in various countries can be heard on various shortwave frequencies . Such unlicensed transmissions by `` pirate '' or `` bootleg '' two way radio operators can often cause signal interference to licensed stations .

 Pirate radio broadcasters who feature programming such as music , talk and other entertainment , can be heard sporadically and in various modes on the shortwave bands .

 Over-the - horizon radar : From 1976 to 1989 , the Soviet Union 's Russian Woodpecker over-the - horizon radar system blotted out numerous shortwave broadcasts daily .

 Ionospheric heaters used for scientific experimentation such as the High Frequency Active Auroral Research Program in Alaska , and the Sura ionospheric heating facility in Russia .

 Shortwave broadcasting ( edit )

 See International broadcasting for details on the history and practice of broadcasting to foreign audiences .

 See Shortwave relay station for the actual kinds of integrated technologies used to bring high power signals to listeners .

 Frequency allocations ( edit )

 Main article : Shortwave bands

 The World Radiocommunication Conference ( WRC ) , organized under the auspices of the International Telecommunication Union , allocates bands for various services in conferences every few years . The last WRC took place in 2007 .

 At WRC - 97 in 1997 , the following bands were allocated for international broadcasting . AM shortwave broadcasting channels are allocated with a 5 kHz separation for traditional analog audio broadcasting .

 Metre Band

 Frequency Range

 Remarks

 120 m

 2.3 -- 2.495 MHz

 tropical band

 90 m

 3.2 -- 3.4 MHz

 tropical band

 75 m

 3.9 -- 4 MHz

 shared with the North American amateur radio 80m band

 60 m

 4.75 -- 5.06 MHz

 tropical band

 49 m

 5.9 -- 6.2 MHz

 41 m

 7.2 -- 7.6 MHz

 shared with the amateur radio 40m band

 31 m

 9.4 -- 9.9 MHz

 currently the most heavily used band

 25 m

 11.6 -- 12.2 MHz

 22 m

 13.57 -- 13.87 MHz

 19 m

 15.1 -- 15.8 MHz

 16 m

 17.48 -- 17.9 MHz

 15 m

 18.9 -- 19.02 MHz

 almost unused , could become a DRM band

 13 m

 21.45 -- 21.85 MHz

 11 m

 25.6 -- 26.1 MHz

 may be used for local DRM broadcasting

 Although countries generally follow the table above , there may be small differences between countries or regions . For example , in the official bandplan of the Netherlands , the 49 m band starts at 5.95 MHz , the 41 m band ends at 7.45 MHz , the 11 m band starts at 25.67 MHz , and the 120 , 90 and 60 m bands are absent altogether . Additionally , international broadcasters sometimes operate outside the normal WRC - allocated bands or use off - channel frequencies . This is done for practical reasons , or to attract attention in crowded bands ( 60m , 49m , 40m , 41m , 31m , 25m ) .

 The new digital audio broadcasting format for shortwave DRM operates 10 kHz or 20 kHz channels . There are some ongoing discussions with respect to specific band allocation for DRM , as it mainly transmitted in 10 kHz format .

 The power used by shortwave transmitters ranges from less than one watt for some experimental and amateur radio transmissions to 500 kilowatts and higher for intercontinental broadcasters and over-the - horizon radar . Shortwave transmitting centers often use specialized antenna designs ( like the ALLISS antenna technology ) to concentrate radio energy at the target area .

 Advantages ( edit )

 Soviet shortwave listener in Borisoglebsk , 1941

 Shortwave does possess a number of advantages over newer technologies , including the following :

 Difficulty of censoring programming by authorities in restrictive countries : unlike their relative ease in monitoring the Internet , government authorities face technical difficulties monitoring which stations ( sites ) are being listened to ( accessed ) . For example , during the attempted coup against Soviet President Mikhail Gorbachev , when his access to communications was limited ( e.g. his phones were cut off , etc . ) , Gorbachev was able to stay informed by means of the BBC World Service on shortwave .

 Low - cost shortwave radios are widely available in all but the most repressive countries in the world . Simple shortwave regenerative receivers can be easily built with a few parts .

 In many countries ( particularly in most developing nations and in the Eastern bloc during the Cold War era ) ownership of shortwave receivers has been and continues to be widespread ( in many of these countries some domestic stations also used shortwave ) .

 Many newer shortwave receivers are portable and can be battery - operated , making them useful in difficult circumstances . Newer technology includes hand - cranked radios which provide power without batteries .

 Shortwave radios can be used in situations where Internet or satellite communications service is temporarily or long - term unavailable ( or unaffordable ) .

 Shortwave radio travels much farther than broadcast FM ( 88 -- 108 MHz ) . Shortwave broadcasts can be easily transmitted over a distance of several thousands of kilometers , including from one continent to another .

 Particularly in tropical regions , SW is somewhat less prone to interference from thunderstorms than medium wave radio , and is able to cover a large geographic area with relatively low power ( and hence cost ) . Therefore , in many of these countries it is widely used for domestic broadcasting .

 Very little infrastructure is required for long - distance two - way communications using shortwave radio . All one needs is a pair of transceivers , each with an antenna , and a source of energy ( such as a battery , a portable generator , or the electrical grid ) . This makes shortwave radio one of the most robust means of communications , which can be disrupted only by interference or bad ionospheric conditions . Modern digital transmission modes such as MFSK and Olivia are even more robust , allowing successful reception of signals well below the noise floor of a conventional receiver .

 Disadvantages ( edit )

 Shortwave radio 's benefits are sometimes regarded as being outweighed by its drawbacks , including :

 In most Western countries , shortwave radio ownership is usually limited to true enthusiasts , since most new standard radios do not receive the shortwave band . Therefore , Western audiences are limited .

 In the developed world , shortwave reception is very difficult in urban areas because of excessive noise from switched - mode power adapters , fluorescent or LED light sources , internet modems and routers , computers and many other sources of radio interference .

 Shortwave listening ( edit )

 A pennant sent to overseas listeners by Radio Budapest in the late 1980s Main article : Shortwave listening

 The Asia - Pacific Telecommunity estimates that there are approximately 600 million shortwave broadcast - radio receivers in use in 2002 . WWCR claims that there are 1.5 billion shortwave receivers worldwide .

 Many hobbyists listen to shortwave broadcasters . In some cases , the goal is to hear as many stations from as many countries as possible ( DXing ) ; others listen to specialized shortwave utility , or `` ute '' , transmissions such as maritime , naval , aviation , or military signals . Others focus on intelligence signals from numbers stations , stations which transmit strange broadcast usually for intelligence operations , or the two way communications by amateur radio operators . Some short wave listeners behave analogously to `` lurkers '' on the Internet , in that they listen only and never make any attempt to send out their own signals . Other listeners participate in clubs , or actively send and receive QSL cards , or become involved with amateur radio and start transmitting on their own .

 Many listeners tune the shortwave bands for the programmes of stations broadcasting to a general audience ( such as Radio Taiwan International , China Radio International , Voice of America , Radio France Internationale , BBC World Service , Voice of Korea , Radio Free Sarawak etc . ) . Today , through the evolution of the Internet , the hobbyist can listen to shortwave signals via remotely controlled or web controlled shortwave receivers around the world , even without owning a shortwave radio . Many international broadcasters offer live streaming audio on their websites and a number have closed their shortwave service entirely , or severely curtailed it , in favour of internet transmission .

 Shortwave listeners , or SWLs , can obtain QSL cards from broadcasters , utility stations or amateur radio operators as trophies of the hobby . Some stations even give out special certificates , pennants , stickers and other tokens and promotional materials to shortwave listeners .

 Shortwave broadcasts and music ( edit )

 Composer Karlheinz Stockhausen

 Some musicians have been attracted to the unique aural characteristics of shortwave radio which -- due to the nature of amplitude modulation , varying propagation conditions , and the presence of interference -- generally has lower fidelity than local broadcasts ( particularly via FM stations ) . Shortwave transmissions often have bursts of distortion , and `` hollow '' sounding loss of clarity at certain aural frequencies , altering the harmonics of natural sound and creating at times a strange `` spacey '' quality due to echoes and phase distortion . Evocations of shortwave reception distortions have been incorporated into rock and classical compositions , by means of delays or feedback loops , equalizers , or even playing shortwave radios as live instruments . Snippets of broadcasts have been mixed into electronic sound collages and live musical instruments , by means of analogue tape loops or digital samples . Sometimes the sounds of instruments and existing musical recordings are altered by remixing or equalizing , with various distortions added , to replicate the garbled effects of shortwave radio reception .

 The first attempts by serious composers to incorporate radio effects into music may be those of the Russian physicist and musician Léon Theremin , who perfected a form of radio oscillator as a musical instrument in 1928 ( regenerative circuits in radios of the time were prone to breaking into oscillation , adding various tonal harmonics to music and speech ) ; and in the same year , the development of a French instrument called the Ondes Martenot by its inventor Maurice Martenot , a French cellist and former wireless telegrapher . Karlheinz Stockhausen used shortwave radio and effects in works including Hymnen ( 1966 -- 67 ) , Kurzwellen ( 1968 ) -- adapted for the Beethoven Bicentennial in Opus 1970 with filtered and distorted snippets of Beethoven pieces -- Spiral ( 1968 ) , Pole , Expo ( both 1969 -- 70 ) , and Michaelion ( 1997 ) .

 Cypriot composer Yannis Kyriakides incorporated shortwave numbers station transmissions in his 1999 ConSPIracy cantata .

 Holger Czukay , a student of Stockhausen , was one of the first to use shortwave in a rock music context . In 1975 , German electronic music band Kraftwerk recorded a full length concept album around simulated radiowave and shortwave sounds , entitled Radio - Activity . The The 's Radio Cineola monthly broadcasts drew heavily on shortwave radio sound .

 Shortwave 's future ( edit )

 PC spectrum display of a modern software defined shortwave receiver Further information : Shortwave listening § Future of shortwave listening

 The development of direct broadcasts from satellites has reduced the demand for shortwave receiver hardware , but there are still a great number of shortwave broadcasters . A new digital radio technology , Digital Radio Mondiale ( DRM ) , is expected to improve the quality of shortwave audio from very poor to standards comparable to the FM broadcast band . The future of shortwave radio is threatened by the rise of power line communication ( PLC ) , also known as Broadband over Power Lines ( BPL ) , which uses a data stream transmitted over unshielded power lines . As the BPL frequencies used overlap with shortwave bands , severe distortions can make listening to analog shortwave radio signals near power lines difficult or impossible .

 Experts disagree on the future of shortwave . According to Andy Sennitt , former editor of the World Radio TV Handbook , `` shortwave is a legacy technology , which is expensive and environmentally unfriendly . A few countries are hanging on to it , but most have faced up to the fact that the glory days of shortwave have gone . Religious broadcasters will still use it because they are not too concerned with listening figures '' .

 However Thomas Witherspoon , editor of shortwave news site SWLingPost.com wrote that `` shortwave remains the most accessible international communications medium that still provides listeners with the protection of complete anonymity '' . According to Nigel Fry , head of Distribution for the BBC World Service Group , `` I still see a place for shortwave in the 21st century , especially for reaching areas of the world that are prone to natural disasters that destroy local broadcasting and Internet infrastructure '' .

 See also ( edit )

 ALLISS -- a very large rotatable antenna system used in international broadcasting

 Amateur radio -- also uses the shortwave bands , but with power levels under 2 kW

 International broadcasting

 List of American shortwave broadcasters

 List of shortwave radio broadcasters

 Long wave

 Medium wave

 Shortwave bands -- shortwave spectrum allocation

 shortwave relay station -- the fundamental way in which programmes are broadcast on shortwave

 SSB -- a method of radio signal modulation

 References ( edit )

 Jump up ^ Grundig Satellit 400 international / professional ShortWaveRadio.ch

 Jump up ^ Inconsistent article : itwissen.info : KW ( Kurzwelle ) SW ( short wave ) Quote : `` ... Der KW - Frequenzbereich ( SW ) liegt zwischen 3 MHz und 30 MHz ( < - 1 . definition ) ... Kurzwelle ist auch eine sendetechnische Bezeichnung für Rundfunk im Frequenzbereich zwischen 2 , 3 MHz und 26 , 1 MHz ( < - 2 . definition ) ... ''

 Jump up ^ oldtimeradio.de : Kleines Radio - Lexikon Quote : `` ... Kurzwellen , Kurzwellenbereich ... Wellenbereich , der von den Rundfunksendern ( je nach geographischer Lage ) von 11 bis 120 m = 26.100 bis 2.300 kHz ... ''

 Jump up ^ darc.de : Amateurfunk Frequenzen Quote : `` ... Grenzwelle ( Kurzwelle ) ... '' , de : Grenzwelle Quote : `` ... Als Grenzwelle wird der Frequenzbereich zwischen 1605 kHz und 3800 kHz bezeichnet , weil er auf der `` Grenze '' zwischen Mittelwelle und Kurzwelle liegt ... ''

 Jump up ^ Grundig Satellit 1000 TR6002 , schematic See at the bottom of the schematic , just below the transformer . In the schematic it is written that the first shortwave band starts at 1.6 MHz ( just after the band end of MW / AM ) : `` KW1 - SW1 - OC1 1 , 6 ... 5 , 0 MHz ''

 Jump up ^ Nebeker , Frederik ( 6 May 2009 ) . Dawn of the Electronic Age : Electrical Technologies in the Shaping of the Modern World , 1914 to 1945 . John Wiley & Sons . pp. 157 -- . ISBN 978 - 0 - 470 - 40974 - 9 .

 ^ Jump up to : Bray , John ( 2002 ) . Innovation and the Communications Revolution : From the Victorian Pioneers to Broadband Internet . IET . pp. 73 -- 75 . ISBN 9780852962183 .

 Jump up ^ Beauchamp , K.G. ( 2001 ) . History of Telegraphy . IET . p. 234 . ISBN 0 - 85296 - 792 - 6 . Retrieved 2007 - 11 - 23 .

 Jump up ^ Burns , R.W. ( 1986 ) . British Television : The Formative Years . IET . p. 315 . ISBN 0 - 86341 - 079 - 0 . Retrieved 2007 - 11 - 23 .

 Jump up ^ `` Full text of `` Beyond the ionosphere : fifty years of satellite communication '' `` . Archive.org . Retrieved 2012 - 08 - 31 .

 Jump up ^ Peter J. Hugill ( 4 March 1999 ) . Global Communications Since 1844 : Geopolitics and Technology . JHU Press . pp. 129 -- . ISBN 978 - 0 - 8018 - 6074 - 4 .

 Jump up ^ Cable and Wireless Plc History Archived 2015 - 03 - 20 at the Wayback Machine .

 Jump up ^ Stormfax . Marconi Wireless on Cape Cod

 Jump up ^ `` 1921 -- Club Station 1BCG and the Transatlantic Tests '' . Radio Club of America . Retrieved 2009 - 09 - 05 .

 Jump up ^ `` Radio Service Bulletin No. 72 , pp. 9 -- 13 '' . Bureau of Navigation , Department of Commerce . 1923 - 04 - 02 . Retrieved 2009 - 09 - 05 .

 Jump up ^ ( 1 ) Archived November 30 , 2009 , at the Wayback Machine .

 Jump up ^ `` Recommendations for Regulation of Radio : October 6 -- 10 , 1924 '' . Earlyradiohistory.us . Retrieved 2012 - 08 - 31 .

 Jump up ^ http://www.twiar.org/aaarchives/WB008.txt

 Jump up ^ Karl Rawer : `` Wave Propagation in the Ionosphere '' . Kluwer , Dordrecht 1993 ISBN 0 - 7923 - 0775 - 5

 Jump up ^ Panasonic / National ShortwaveRadio.ch

 Jump up ^ `` Feld Hell Club '' . Google Sites . Google . Retrieved 9 January 2017 .

 Jump up ^ Ian Robertson Sinclair , Audio and Hi - Fi Handbook , Newnes , 2000 ISBN 0 - 7506 - 4975 - 5 pp. 195 -- 196

 Jump up ^ Christopher H. Sterling ( March 2004 ) . Encyclopedia of Radio 3 - Volume Set . Routledge . pp. 538 -- . ISBN 978 - 1 - 135 - 45649 - 8 .

 Jump up ^ Hearst Magazines ( January 1940 ) . Popular Mechanics . Hearst Magazines . pp. 62 -- .

 Jump up ^ `` IARU Monitoring System '' . iaru.org . International Amateur Radio Union ( IARU ) . Retrieved 28 November 2017 .

 Jump up ^ Andrew R. Yoder ( 2002 ) . Pirate Radio Stations : Tuning in to Underground Broadcasts in the Air and Online . McGraw Hill Professional . ISBN 978 - 0 - 07 - 137563 - 4 .

 Jump up ^ Vladimir Bychkov ; Gennady Golubkov ; Anatoly Nikitin ( 17 July 2010 ) . The Atmosphere and Ionosphere : Dynamics , Processes and Monitoring . Springer Science & Business Media . pp. 104 -- . ISBN 978 - 90 - 481 - 3212 - 6 .

 Jump up ^ Nationaal Frequentieplan

 Jump up ^ http://www.w4uvh.net/dxld7078.txt

 Jump up ^ Habrat , Marek . `` Odbiornik `` Roksana '' ( Radio constructor 's recollections ) `` . Retrieved 2008 - 08 - 05 .

 Jump up ^ ( 2 ) Archived February 10 , 2005 , at the Wayback Machine .

 Jump up ^ Arlyn T. Anderson . `` Changes at the BBC World Service : Documenting the World Service 's Move From Shortwave to Web Radio in North America , Australia , and New Zealand '' , Journal of Radio Studies 2005 , Vol. 12 , No. 2 , Pages 286 -- 304 doi : 10.1207 / s15506843jrs1202_8 mentioned in ( 3 ) WWCR FAQ

 Jump up ^ Web - Controlled Radios DXing.com

 ^ Jump up to : Karl Heinrich Wörner ( 1973 ) . Stockhausen ; Life and Work . University of California Press . pp. 76 -- . ISBN 978 - 0 - 520 - 02143 - 3 .

 ^ Jump up to : David Sheppard ( 1 May 2009 ) . On Some Faraway Beach : The Life and Times of Brian Eno . Chicago Review Press . pp. 275 -- . ISBN 978 - 1 - 55652 - 107 - 2 .

 ^ Jump up to : The Wire. C. Parker . 2000 .

 Jump up ^ Laura Dolp ( 13 July 2017 ) . Arvo Pärt 's White Light . Cambridge University Press . pp. 83 -- . ISBN 978 - 1 - 107 - 18289 - 9 .

 Jump up ^ Tim Barr ( 31 August 2013 ) . Kraftwerk : from Dusseldorf to the Future With Love . Ebury Publishing . pp. 98 -- . ISBN 978 - 1 - 4481 - 7776 - 9 .

 Jump up ^ Radio Cineola www.thethe.com Archived December 18 , 2011 , at the Wayback Machine .

 ^ Jump up to : Careless , James . `` The Evolution of Shortwave Radio '' . Radio World . NewBay Media . Retrieved 16 February 2018 .

 Jump up ^ Halid Hrasnica ; Abdelfatteh Haidine ; Ralf Lehnert ( 14 January 2005 ) . Broadband Powerline Communications : Network Design . John Wiley & Sons . pp. 34 -- . ISBN 978 - 0 - 470 - 85742 - 7 .

 Ulrich L. Rohde , Jerry Whitaker `` Communications Receivers , Third Edition '' McGraw Hill , New York , NY , 2001 , ISBN 0 - 07 - 136121 - 9 .

 External links ( edit )

 SWLing.com -- A beginner 's guide to shortwave radio listening .

 Glenn Hauser 's World of Radio website

 Space Weather and Radio Propagation Center View live and historical data and images of space weather and radio propagation .

 Short - wave radio , Snap and crackle goes pop , Life in the old wireless yet The Economist article describing pros and cons of short wave radio since the Cold War .

 `` Short - Wave Radio Telephone is Success in Tests '' Popular Mechanics , July 1931 , mid page experiments carried out for the French and British governments

 Que Escuchar en la Onda Corta en Español website

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National Senior certificate - wikipedia

 National Senior certificate

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 This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . ( April 2010 ) ( Learn how and when to remove this template message )

 The National Senior Certificate or NSC is a high school diploma and is the main school - leaving certificate in South Africa . This certificate is commonly known as the matriculation ( matric ) certificate , as grade 12 is the matriculation grade . The NSC , previously known as the Further Education and Training Certificate or FETC , replaced the Senior Certificate with effect from 2008 and was phased in starting with grade 10 in 2006 .

 Pupils study at least seven subjects , including two compulsory official South African languages , either Mathematics or Mathematical Literacy , Life Orientation and three elective subjects .

 Subjects are all taken on the same level - there is no higher or standard grade as in the past . There are three pass levels , each with different pass requirements. First is a pass with Higher certificate , one must obtain 40 % in home language , 40 % in two other subjects and must obtain 30 % in three other subjects . A learner who passed matric with higher certificate level , can not enroll for a University Degree nor a Diploma at an institute of higher learning . The mean mark in any subject is usually about 55 . Only a small proportion of candidates score an ' A ' in any subject ( from as little as 2 % to a maximum of about 10 % in subjects taken by highly select groups . ) A further 8 -- 15 % are likely to gain a ' B ' and about 20 -- 25 % achieve a ' C ' grade . The National Senior Certificate is a group certificate and records an aggregate mark .

 The Department of Basic Education has responsibility for general educational policy to be implemented by nine provincial education departments and private providers such as the Independent Examinations Board ( IEB ) . There are nine provincial examination boards and three independent boards , of which the IEB is the biggest . The IEB operates on a national level catering primarily for independent schools .

 Contents

 ( hide )

 1 Subject requirements

 1.1 Group A : Fundamentals ( Compulsory )

 1.2 Group B : Electives

 2 Life Orientation

 3 Assessment

 4 Level system ( 1 to 7 )

 5 The 5 % language compensation

 6 University entrance

 7 See also

 8 References

 9 External links

 Subject requirements. ( edit )

 Learners study at least 7 subjects - 4 compulsory and at least 3 electives . All subjects are written on one grade only and are no longer written on Higher or Standard Grade . Not all schools offer the full range of Elective subjects listed here . Each school may offer subjects specific to its academic orientation . For example , Agriculture Schools offer the agriculture - orientated subjects whereas technical Schools offer the practical and mechanical - orientated subjects. V

 Group a : fundamentals ( compulsory ) ( edit )

 Learners must study 4 compulsory subjects ,

 Two official languages of South Africa must be studied :

 Afrikaans

 English

 Ndebele

 Northern Sotho

 Sesotho

 Siswati

 Tsonga

 Tswana

 Venda

 Xhosa

 Zulu

 Mathematics or Mathematical Literacy

 Life Orientation

 Group B : electives ( edit )

 At least 3 subjects from the following :

 Accounting

 Agricultural Management Practices

 Agricultural Sciences

 Agricultural Technology

 Business Studies

 Civil Technology

 Computer Applications Technology ( previously Computer Studies Standard Grade - Literacy )

 Consumer Studies

 Dance Studies

 Design

 Dramatic Arts

 Economics

 Electrical Technology

 Engineering Graphics & Design

 Geography

 History

 Hospitality Studies ( previously Home Economics )

 Information Technology ( previously Computer Studies Higher Grade - Programming )

 Life Sciences ( previously Biology )

 Mechanical Technology

 Music

 Physical Science

 Religion Studies

 Second Additional Language

 Third Additional Language

 Tourism

 Visual Arts

 Life Orientation ( edit )

 Life Orientation ( colloquially abbreviated as `` LO '' ) has been introduced into the senior high school phase as an examination subject . Life Orientation is a broad - learning subject that covers non-academic skills needed in everyday life . Life Orientation is examined , marked and moderated internally and comprises the following sections :

 World of Work , helping learners find guidance in their choice of career and prepare them for the working world

 Health Education , this sections includes sex education , HIV / Aids talks , pregnancy , etc .

 Physical Education , involves physical exercise and training , it is done on a separate basis but eventually forms part of the Life Orientation mark

 Religious Education , each South African school decides which religion to adhere to ( as according to the South African schools act ) , learners may be exempted from these classes . In practice this means that learners may be exempted from , example , the Bible Studies class , but are compelled to attend the Religious Studies class ( which deals with all religions as a study ) .

 Citizenship and Responsibility , this section teaches learners about their rights and their duties as citizens .

 Assessment ( edit )

 There are three types of subjects :

 General Subjects

 An end - of - year examination : 75 % of the total mark

 Portfolio ( Continuous Assessment ) : 25 % of the total mark

 Practical Subjects

 An end - of - year examination : 50 % of the total mark

 Portfolio ( Continuous Assessment ) : 25 % of the total mark

 Practical component : 25 % of the total mark

 Language Subjects

 An end - of - year examination : 50 % of the total mark

 Portfolio ( Continuous Assessment ) : 25 % of the total mark

 Oral Examination : 25 % of the total mark

 Continuous Assessment ( CASS ) includes all the tests , examinations , tasks , activities , orals and projects done throughout the year . Matric results are usually out of 400 marks .

 Level system ( 1 to 7 ) ( edit )

 Level 7 : 80 - 100 % ( Outstanding achievement )

 Level 6 : 70 - 79 % ( Meritorious achievement )

 Level 5 : 60 - 69 % ( Substantial achievement )

 Level 4 : 50 - 59 % ( Moderate achievement )

 Level 3 : 40 - 49 % ( Adequate achievement )

 Level 2 : 30 - 39 % ( Elementary achievement )

 Level 1 : 0 - 29 % ( Not achieved - Fail )

 The 5 % language compensation ( edit )

 Language compensation is described by several sources :

 `` To the final mark is added the language compensation , which is 5 % of the mark attained by the candidate for all non-language subjects , for candidates whose mother tongue is not English or Afrikaans . The 5 % compensates learners for the disadvantage suffered by these candidates being instructed in a language that is not their mother tongue . '' ( Written reply to parliamentary question in 2011 )

 `` The compensation applies to learners whose first language is neither English nor Afrikaans and who offer an African language as their first language . They receive an additional 5 % on their non-language subjects . The measure was first introduced in 1999 by the South African Certification Council . '' ( Written reply to parliamentary question in 2007 , )

 Dr Sizwe Mabizela , Chairperson of Council , Umalusi has provided further explanation : `` This is the most misunderstood concept in this country . In terms of the policy on language compensation , learners who offer an African language as Home Language and do not offer Afrikaans or English as Home language qualify for a 5 % language compensation on the mark they have obtained in a non-language subject . For example a learner who obtains a mark of zero ( 0 ) out of 300 will obtain 5 % of zero ( which is zero ) for language compensation ; a learner who obtains 10 out of 300 will receive 5 % of 10 , which is 0 , 5 marks , for language compensation ; a learner who obtains 100 out of 300 marks will obtain an additional 5 marks for language compensation . ''

 This kind of compensation has some impact on pass rates , but does provide significant impact at the upper end of the scale , affecting those applying for admission to university . For example , a qualifying learner obtaining 95 % would receive 95 x 1.05 = 99.75 % ( which rounds to 100 % ) . A learner obtaining 40 % would receive 40 x 1.05 = 42.0 % .

 University entrance ( edit )

 In addition to minimum grades required in each subject , universities either set their own entrance tests and / or use the National Benchmark Tests ( NBT ) . To study for a bachelor 's degree at a South African university requires that the applicant has at least an NSC endorsed by Umalusi , with a pass of 30 % in the chosen university 's language of learning and teaching , as well as a level 4 or higher in the following list of designated , 19 - credit subjects :

 Accounting

 Agricultural Sciences

 Business Studies

 Dramatic Arts

 Economics

 Engineering Graphics and Design

 Geography

 History

 Consumer Studies

 Information Technology

 Languages ( one language of learning and teaching at a higher education institution and two other recognised language subjects )

 Life Sciences

 Mathematics

 Mathematical Literacy

 Music

 Physical Sciences

 Religion Studies

 Visual Arts

 See also ( edit )

 High school # South Africa

 Matriculation in South Africa

 Independent Examinations Board

 References ( edit )

 Jump up ^ SOUTH AFRICAN NATIONAL ASSEMBLY : QUESTION 757 , DATE OF PUBLICATION OF INTERNAL QUESTION PAPER : 11 / 03 / 2011 ( INTERNAL QUESTION PAPER : 06 / 2011 )

 Jump up ^ SOUTH AFRICAN NATIONAL ASSEMBLY : WRITTEN REPLY TO QUESTION 469 , DATE OF PUBLICATION IN INTERNAL QUESTION PAPER : 26 - 03 - 2007 ( INTERNAL QUESTION PAPER NO. : 10 - 2007 )

 Jump up ^ Politicsweb , 3 January 2011 , `` Umalusi explains matric mark adjustments '' , Dr Sizwe Mabizela , 03 January 2011

 Jump up ^ http://nbt.ac.za/ About NBT Retrieved 21 March 2011

 Jump up ^ http://wced.pgwc.gov.za/circulars/circulars08/e33_08.html

 External links ( edit )

 Department of Education official site

 IEB official site

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 This page was last edited on 18 April 2018 , at 19 : 39 .

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