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TVandaudiodevices:areviewEarlyhistoryofTVThefirstpublicshowingsofwirelessTVtransmissionweremadein1925intheUSAandin1926inBritain.Later,in1928,thefirstlong-distanceTVbroadcastwasmadebetweentheUKandtheUSA.Regularpublicbroadcastingfollowedshortlyafter,firstbeginningon11May1928inNewYorkandinLondonon20August1929.ManydifferentpeoplecontributedtothedevelopmentofTV.Becauseofthis,itisstilluncertainwhoinventedTV.Altogether,theremencouldberesponsible.VladimirZworykin,aRussianlivingintheUSA,PhiloFarnsworth,afarmboyfromUtahintheUSA,andJlhnLogieBairdfromScotlandallinventedearlyformsofTVbetween1923and1927.Afewyearslater,colourTVwasfirstshownin1929.Ittookmorethantwodecades,though,until1951,forcolourbroadcaststobeginintheUSA.By1967,mostbroadcastswereincolourandwithinfiveyears,morecolourthanblack-and-whiteTVsetswerebeingused.Themodernage:cableTV,satelliteTV,digitalTV,…CableTVbeganin1948intheUSA,butittook50yearsbefore66percentofAmericanhouseholdshadit.SatelliteswereusedtobroadcastTVbeginningin1962.SomeconsiderdigitalTVtobesuperiortosatelliteTVbecauseitallowsthesameservicestobedeliveredwithclearerpicturesthanbefore.InternationalstandardsfordigitalTVwereestablishedin1989andwithinfiveyears,consumersintheUSAhadaccessto200channels.By2004,digitalTVsignalswerebeingreceivedby55percentofhouseholdsinBritain.In1996,acompletelynewconceptwasintroducedwhenthefirstWebTVset-topboxescameontothemarket.ThiscombinestheTVsetwiththeWorldWideWeb.WithinteractiveTVprogramming,youcanplayalongwithgameshows,respondtoquestionnairesandchattootherviewers.EarlyhistoryofaudiodevicesItallbeganin1877whenThomasEdisonmadethefirstrecordingofahumanvoice.Tenyearslater,thefirstrecordplayerwasdeveloped.ItwasinventedbyEmileBerliner,aGermanlivingintheUSA.Atthattime,therecordplayerhadtobewouldupbyhandandonlyplayedarecordfortwominutes.In1958,thefirstLPs(long-playrecords)cameontothemarket.Taperecordsandplayers1931wastheyearwhenaGermancompanybegantomakethefirsttaperecorders,whichcouldrecordandplaysoundsonatapewouldarounda