Fixed telephone

Basicoverview

Asimpletelephonecircuitincludesreceiversandtransmitters,powersupplyandlinesplacedinAandBrespectively,andthesepartsareconnectedinseries.

Infact,fixed-linetelephonesshouldalsoincludefunctionssuchasringinglines,dialingloops,andcallerIDdisplay.Thetelephonesalsoneedtocooperatewiththetelecommunicationsbureau’sswitchtocompletethedialingwork.

Nowadays,fixed-linetelephonesdon’tneedtobesotroublesome.Youonlyneedtoliftthehandsettomakeacall.Andinthenewproductanddesign,theadvantagesofcordlessphonesareintegrated.Thereisaportablelandlineonthebaseofthelandline,whichcanmakecallsduringfreewalkingmotionswithintheallowedrangeofthelandline,andhasaqualitycalleffect.Fixedtelephonesarenolongerfixed.

Historyofdevelopment

Historyoftelecommunications

From"ZhouYouwangFenghuolords"to"BambooLetters",from"DriftingBottle"toNo.1inhumanhistoryAtelegram-"WhatamiracleGodhascreated."Inthepast100years,communicationtechnologyhasdevelopedrapidlywiththehelpofmoderntechnology.Letuslookbackandtakealookatthesceneryalongtheway.

TalkingaboutthehistoryoftelecommunicationsinChinaandabroad.Accordingtoresearch,peopleinancientChinaknewthatbeaconwasusedtotransmitmessagesoverlongdistancesduringtheShangandZhoudynasties..Inthebook"OneHundredYearsofTelephone"publishedbytheInternationalTelecommunicationUnion,itismentionedthatin968AD,theChineseinventedsomethingcalled"BambooLetter",whichisconsideredtheprototypeofthetelephone.Althoughthesestoriesreflecttheingenuityofourancestors,ifwewanttounderstandthedevelopmenthistoryofmoderntelecommunicationstechnology,westillhavetostartfromEurope.

OriginatedinEurope

In1793,theFrenchChappébrotherssetupa230-kilometer-longcradle-typelinetotransmitinformationbetweenParisandLille.Thisisacommunicationsystemconsistingof16signaltowers.Inthesignalmachine,thesignalpersonusesropesandpulleystocontrolthedifferentanglesofthebrackettoindicaterelevantinformation.Atthattime,FranceandAustriawerefighting,andthesignalsystemtookthenewsofthevictoryofConde-sur-AesfromtheAustrianarmytoParisinjustonehour.Inthefuture,Belgium,theNetherlands,Italy,GermanyandRussiahavealsoestablishedsuchcommunicationsystems.ItissaidthatoneofthetwobrothersChapewasthefirsttousetheword"telegram".

Europe'sresearchonlong-distancesoundtransmissionbeganinthe17thcentury.ThefamousBritishphysicistandchemistRobertHookerfirstproposedtheproposaloftransmittingvoiceoverlongdistances.In1796,Hughesproposedamethodofrelayingvoiceinformationwithamicrophone,andcalledthismethodofcommunication—Telephone,whichhasalwaysbeenused.

In1832,onamailshipsailingintheAtlanticOcean,AmericandoctorJacksontoldpassengersabouttheprincipleofelectromagnets.Amongthepassengers,the41-year-oldAmericanpainterMorsewasdeeplyattracted.Atthattime,theFrenchsignalsystemcouldonlytransmitinformationformileswithsight.Morsedreamedofusingelectriccurrenttotransmitelectromagneticsignalsandtransmitmessagesthousandsofmilesawayinaninstant.Sincethen,Morse'slifehasundergoneafundamentalchange.

Morsewasinspiredbythefactthatthecurrentflowinginthewirewillsparkwhenthewireissuddenlycutoff:ifthecurrentcutoffforamomentandthesparkisemittedasasignal,thecurrentisturnedonandthereisnospark.Asanothersignal,thecurrenton-timeislengthenedandusedasasignal.Thecombinationofthesethreesignalscanrepresentallthelettersandnumbers,andthetextcanbetransmittedtoaremoteplaceinthewirethroughthecurrent.In1837,MorsefinallydesignedthefamousMorsecode,whichusesdifferentcombinationsof"dot","stroke"and"space"torepresentletters,numbers,punctuationandsymbols.OnMay24,1844,intheFederalSupremeCourtChamberoftheCapitolinWashington,Morsepersonallymanipulatedthetelegraph.Followingaseriesof"dot"and"stroke"signals,itwas64kilometersawayinBaltimore.Receivedtheworld'sfirsttelegramconsistingof"di"and"click"sounds.

Inventedthetelephone

TheinventorofthetelephoneisBell.HeappliedforatelephonepatentintheUSPatentOfficeonFebruary14,1876.Infact,justtwohoursafterhefiledanapplication,apersonnamedE.Grayalsoappliedforatelephonepatent.

Beforethetwoofthem,manypeopleinEuropewerealreadycarryingoutideasandresearchinthisarea.Asearlyas1854,theprincipleofthetelephonewasconceivedbytheFrenchmanBoussard,and6yearslater,theGermanReisrepeatedthisidea.Theprincipleis:connecttwothinmetalsheetswithwires,andwhenonesidemakesasound,themetalsheetsvibrateandbecomeelectricity,whichistransmittedtotheotherside.Butthisisonlyanassumption.Theproblemisthestructureofthemicrophoneandreceiver,howcanthemechanicalenergyofsoundbeconvertedintoelectricalenergyandtransmitted.

Atfirst,Bellusedanelectromagneticswitchtoformapulsesignalthatopensandcloses,butthismethodisobviouslynotfeasibleforhighfrequenciessuchassoundwaves.Thefinalsuccessstemsfromanaccidentaldiscovery.OnJune2,1875,inanexperiment,heconnectedametalsheettoanelectromagneticswitch.Unexpectedly,inthisstate,thesoundturnedintoanelectriccurrent.Theprincipleofanalysisisthatthemetalsheetvibratesduetosoundandacurrentisgeneratedintheelectromagneticswitchcoilconnectedtoit.Thisprincipleisknowntoastudentwhohasstudiedphysicsinjuniorhighschool,butatthattimeitwasundoubtedlyaveryimportantdiscoveryforBell.

Gray’sdesignprincipleisdifferentfromBell.Itusesthechangeinresistanceoftheliquidinsidethemicrophone,whilethereceiverisexactlythesameasBell’s.In1877,Edisonobtainedapatentfortheinventionofthecarbonmicrophone.Atthesametime,manypeoplehavemadevariousimprovementstothewaythephoneworks.Thepatentdisputewassocomplicatedthatitdidn'tcometoanenduntil1892.OnereasonforthissituationwasthattheUnitedTelegraphCompany,thelargestWesternUnitedTelegraphCompanyintheUnitedStates,boughtthepatentrightsofGrayandEdisontofightBell'stelephonecompany.Theresultofthelong-termpatentdisputewasthatthetwopartiesreachedanagreement.WesternUnitedTelegraphCompanyfullyrecognizedBell'spatentrightsandnolongerinvolvedinthetelephoneindustry.Theexchangeconditionwastoshare20%ofBellTelephoneCompany'srevenuewithin17years.

Technologicaldevelopment

Inthedecadesafterthetelephonewasinvented,alargenumberofpatentswereappliedforaroundthetelephone’sbusinessandtechnologyissues,andStrowger’s"automaticdialingsystem"reducedVariousproblemscausedbymanualwiring,theapplicationofdrybatteriesreducesthesizeofthephone,andtheapplicationofloadedcoilsreducesthesignallossoflong-distancetransmission.In1906,LeeDeinventedtheelectronictesttube,anditsamplificationfunctionledthedirectionoftelephoneservice.Later,BellTelephoneLaboratoriesmadeanelectronictriodeaccordingly.Thisresearchisofgreatsignificance.OnJanuary25,1915,thefirstinter-districttelephonelinewasopenedbetweenNewYorkandSanFrancisco.Ituses2500tonsofcopperwire,130,000telephonepolesandcountlessloadingcoils,anduses3vacuumtubeamplifiersalongthewaytostrengthenthesignal.OnJuly1,1948,scientistsatBellLabsinventedthetransistor.Thisisnotonlyofgreatsignificanceforthedevelopmentofthetelephone,butalsohasahugeimpactonallaspectsofhumanlife.Inthefollowingdecades,alargenumberofnewtechnologiesemerged,suchastheproductionofintegratedcircuitsandtheapplicationofopticalfibers,whichplayedaveryimportantroleinthedevelopmentofcommunicationsystems.

DevelopmentofChina

AftertheOpiumWar,whileWesternpowersplunderedlandandwealthinChina,theyalsobroughtmodernpostalservicesandtelecommunicationstoChina.In1900,mycountry'sfirstlocaltelephonecameoutinNanjing;from1904to1905,RussiasetuparadiostationfromYantaitoNiuzhuang.China'sancientpostalpostsystemandprivatecommunicationinstitutionshavebeengraduallyreplacedbyadvancedpostalservicesandtelecommunications.

DuringtheRepublicofChina,China’spostandtelecommunicationswerestillunderthecontrolofWesternpowers.Coupledwithyearsofwarandchaos,communicationsfacilitiesareoftendestroyed.DuringtheAnti-JapaneseWar,theJapaneseimperialiststransformedandexpandedthetelecommunicationsnetworksystemforthepurposeofwarneedsandlong-termruleofChina.TheytookadvantageofChina’seconomicandtechnologicalbackwardnessandthecorruptionofthepoliticalsystematthattime.ControlofChina’scommunicationsindustry.

Before1949,thedevelopmentofChina'stelecommunicationssystemwasslow.By1949,thetelephonepenetrationrateinChinawasonly0.05%,andtherewereonly260,000telephoneusers.

After1949,theCentralPeople'sGovernmentquicklyresumedanddevelopedcommunications.TheBeijingTelegraphBuilding,builtin1958,becameanimportantmilestoneinthehistoryofcommunicationsdevelopmentinNewChina.Duringtheten-year"CulturalRevolution",postandtelecommunicationswerehitagain,losingmoneyallthetime,andbusinessdevelopmentstagnated.By1978,thenationaltelephonepenetrationratewasonly0.38%,whichwaslessthan1/10oftheworldlevel.ThetotalnumberoftelephonesownedbyChina,whichaccountsfor1/5oftheworld’spopulation,waslessthan1%ofthetotalnumberoftelephonesintheworld.Lessthanone,75yearsbehindtheUnitedStates.Theproportionofswitchautomationislow.Mostcountiesandruralareasstilluse"handles".Long-distancetransmissionmainlyreliesonopenwiresandanalogmicrowaves.EveninBeijing,20%oflong-distancecallscannotbemadeeveryday,and15%canonlybeansweredafter1hour.Pass.ThosewhocallintheTelegraphBuildinghavetotaketheirlunchtolineup.

In1978,thenationaltelephonecapacitywas3.59million,with2.14millionusers,andthepenetrationratewas0.43%.

Afterthereformandopeningup,thebackwardcommunicationnetworkhasbecomethebottleneckofeconomicdevelopment.Sincethemid-1980s,theChinesegovernmenthasacceleratedtheconstructionofbasictelecommunicationsfacilities.ByMarch2003,thenumberoffixedtelephoneusersreached225,626millionand219,491millionmobilephoneusers.

Inancientandmoderntimes,athomeandabroad,howmanypeoplehaveworkedhardtotransmitinformationfasterandbetter.Inthemorethanonehundredyearsofthedevelopmentoftelecommunications,peoplehavetriedvariouscommunicationmethods:theoriginaltelegraphusedsimilar"The"digital"wayofconveyinginformation;later,thetelephonethattransmitsinformationbyanalogsignalappeared;withtheadvancementoftechnology,thedigitalmethodwasonceagainvaluedforitsobviousadvantages,digitalprogram-controlledexchanges,digitalmobilephones,opticalfiberdigitaltransmission...…Thewheelofhistoryisstilladvancing.

ThelatestdatashowsthatonlyhalfofthehouseholdsintheUnitedStateshavefixed-linephonesinstalled;inChina,theproportionisevenlower.InAugust2015,theMinistryofIndustryandInformationTechnologyreleasedasurveyreporton“CommunicationLevelsbyProvincesintheSecondQuarterof2015”.Theresultsshowedthatasofthesecondquarterof2015,thepenetrationrateoffixed-linetelephonesinChinawasfarlowerthanthatofmobilephones;fixed-lineandThehighestpenetrationrateofmobilephonesisinBeijing.Itcanbeseenthattheoverallpenetrationrateoffixedtelephonesisbetween20%and30%.Thepenetrationrateofmobilephonesisabove60%.

Acentury-oldtelephone

Sincethetelephonewasinvented,therehavebeenmanychangesfromtheworkingprincipletotheappearancedesign.Now,pleasefollowustowalkthecentury-olddevelopmentofthistelephone.theway.Thesephonesarethecollectionsofantiquephonecollectorsfromallovertheworld.

August15,1784---YaowangCommunication

Avisualcommunicationmethodcalled"YaowangCommunication"wasfirstusedinLilleandParis,FranceUsedbetween.

1796---Relaymicrophonetotransmitvoice

BritishHughesproposedthemethodoftransmittingvoicethroughmicrophonerelayandnameditTelephone,Thenamehasalwaysbeenused.

1832---Thetelegraphthatthegalvanometerpointerdeflectedtoreceiveinformation

RussiandiplomatSchillingmadeagalvanometerpointerdeflectedtoreceiveinformationTelegraphmachine.

In1835---Telegraphmachine

TheAmericanMorseinventedthetelegraphmachinefortelegraphtransmissionusingtheprincipleofelectromagnetics.

InJune1837,theEnglishmanCookobtainedthefirsttelegraphinventionpatent.Thetelegraphmachinehemadewasfirstusedontherailway.

From1837to1838,Morseinventedthe"on"and"off"ofthecurrenttocompileacoderepresentingnumbersandletters-Morsecode.

In1843,MorsebuiltatelegraphlinefromWashingtontoBaltimore,withatotallengthof64.4kilometers.

OnMay24,1844,MorsesentthefirsttelegraminhumanhistorytoBaltimoreattheCapitol:"WhatamiracleGodhascreated."

OnAugust28,1850,thefirstsubmarinecablewasrunbybrothersJohnandJacobBrettbetweenCapeGris-NezinFranceandCapeLiselandinEnglandItwaslaidintheopensea,butitwasinterruptedafteronlyafewtelegrams.Itturnedoutthatafishermanhookedupapieceofcablewithatrawlandcutoffasectionhappilyboastingofthisrare"seaweed"specimentoothers,sayingthatitwasfilledwithgoldinsurprise.

March10,1876---ScotsmanBellinventedthetelephone

"Mr.Watson,comeandhelpme"becamethefirstmanAvoicesentoverthephone.AtthattimeBellsplashedtheacidinthemicrophoneonhisleg.

1878---Handheldphone

ThisphonewasmadeinGermanyin1878byWernerSiemens.Itsearpieceandmicrophoneareone,andtheyareusedinterchangeablywhenlisteningandspeaking.

1879---Boxphone

ThisphoneisequippedwithamagneticgeneratorproducedbyViaductManufacturingCompany,whichismadeofmahoganyandisalsoequippedwithAcylindricalearpiece.

1880---BellTelephone

ThisisthefirsttelephoneusedinEurope.Itreplacesthetelegraphandismoreadvancedthanthemagneticmotorphoneequippedwithahandle.

1881,1882---Magneticgeneratorwallphone

ThephoneontheleftiscalledtheAmericanBelltype,manufacturedin1881andlocatedinCopenhagenUsedbytheInternationalBellTelephoneCompany.ManufacturedbyL.M.Ericsson.Thisphonebecamepopularattheendofthelastcentury.

1885---"EiffelTower"magnetgeneratorphone

ThisphonewasmanufacturedbyL.M.Ericssonin1885.Atthetimethiswasthefirstphoneplacedonthedesktop.Themicrophoneissetontherotatingarm,andthecrankisusedtoconnecttotheswitch.

1885,1902---MagneticGeneratorWallPhone

byFerdinandE.StensenwasmadeinCopenhagenin1885andwasthefirsttelephonemadebytheDanes.ThisoneismadeatEmilMdlersTelephoneCompanyinHosen.

1885---Woodenstanddeskphone

Themanufacturerandplaceoforiginareunknown.

1892---electricfoldingcupboarddeskphone

Thiskindofphonewasmostlyusedinhomes,hotelsandtelephonebooths.

1892---"EiffelTower"telephonewithhandset

Thisisatrueclassictelephone,in1892,byLMEricssonmanufacture.Thisphonehasspreadallovertheworldandnearlyonemillionunitshavebeenproduced.

1893---"coffeepotstyle"telephone

ThistelephonehasonlyafewsamplesinDenmark,anditistherichestforcollectorsAttractivenessandcollectionvalue.In1899,digitalmechanicalwallphone

Thiskindofdigitalmechanicalphonehastwotypes:walltypeanddesktype.

1900---uprightdeskphone

Thisround-bellieddeskphoneisnickel-platedbronze.Thereisastrongbakeliteunderthehangingpole.Italsohasaperipheralearpiecethatyoucanshowoff.

1900---uprightconedeskphone

Thisphonewasnicknamed"oilpot"becauseofitsappearance.In1900,the20-linesplitphone

Thisparagraphistheso-called20-linesplitphone.Canonlybeusedforinternalcalls,manufacturedbyL.M.EricssonSweden.

1901---MagneticGeneratorDeskPhone

ThismodelwasmadeinCopenhagenbyFerdinandE.StensensTelefonfabrikin1901.Payattentiontoitsearpiece,whichishungonthehookseparately.Itmaybebecausethequalityoftelephoneaccesswasnothighatthattime,andsometimesitwasnecessarytolistenwithtwoears.

1902---Kelloggcornerdeskphone

Thiskindofcornerdeskphonewasmostlyusedinhomes,officesandtelephonebooths.ItismanufacturedbyHardwoodTelephoneCompany,USA.ItwasboughtfromafarmerinasmalltowninCalifornia.

1902---Publicbatterywallphone

Thiskindofphonedoesnotneedtoturnthehandle,justpickupthemicrophoneandtalktotheoperatordirectly.ItwasboughtfromanantiqueshopinSanFrancisco.

1904---Magneticgeneratorcollineartelephone

ThistelephonewasmanufacturedbyL.M.Ericssomin1904.Thisphonecanbesharedbyfourusersononephoneline.OnFebruary17,1753,theideaof​​usingelectriccurrenttocommunicatewasfirstproposedinamagazinecalledTheScotsman,andthearticlewassignedC.M.

1904---"Spider-like"civilianbandphone

L.M.Ericsson’sfirstcivilianbandphone.In1905,Chicago’stree-styledeskphone

Thisdeskphonewascalled"potbelly",namedafterthebulgeinthemiddleofthehandle.

1905---PorchIntercom

Thisisa32-doorporchwalkie-talkieofConnecticutTelecom.

1905--Eleven-digitdialingdeskphone

Ituses11-digitdialing.

1907---"Germanmode"radiobandphone

ThisphonewasmanufacturedbyE.Zwuetysch&CoinGermanyin1907.Theemergenceofcansolvetheproblemoftoolongcallwaitingtimetoacertainextent.

1907---Magneticgeneratortelephone

ThistelephonewasmanufacturedbyL.M.Ericssonin1907.Itisworthnotingthatwhenansweringthephone,hangthehandsetonaseparatehook.Thiswastheunifiedstandardoftelephonemanufacturersatthattime.

1908---CH-08loudspeakerphone

IntroducedbyKTAS.

1910---InternetPhone

ThisisanuprightdesktopInternetphoneproducedbyS.H.Couch,whichisusedforcommunicationbetweenoffices.

1912---arrangementmachineforofficeuse

Thisphonecanhave17extensionsatthesametimethroughthehost,andeachextensioncanmakeoutgoingcalls.,Andtheextensionscanalsobeconnectedtoeachother.

1912---CH-08wallphone

Thisphonewasproducedin1912andmadebytheDanesinCopenhagen.ItcanautomaticallySendandreceivetelegrams.

1912---MagneticGeneratorTelephone

ThetelegraphandfaxtelephonemadebyL.M.Ericssonisoftenusedinremoteareasorsmallislands.

1914---Magnavoxantinoisedeskphone

TheuniquenessofthisphoneThedesignisthatwhenspeakingintothemicrophone,thesoundpassesthroughthesmallholeatthetopofthephonetovibratethevibratingplateinthephone.Noiseiseliminatedwhenitentersthemicrophone.Itsdual-rotatingearpiecehelpstoblockuselessnoise.

1914---Magnavoxanti-noisedeskphoneB1type

Italsohasthefunctionofeliminatingnoise.

1914---Magneticgeneratortelephone

ManufacturedinHORWENSin1914,itcanbeusedfortelegraphandfax.

1915---Veaudeskphone

Theinformationisunknown.

1915---Home-madewall-mountedphone

ThisphonewasfoundinanabandonedfarminEasternOregon.Therearenearly20abandonedfarmsinthelocalareawithtracesofthephonehangingonthewalls.

1920---Magneticgeneratorwallphone

Thisphonewasmanufacturedin1904andupdatedin1920.ItisequippedwithRotateredbuttonforconversion.

1927---D-08semi-automatictelephone

Theappearanceofthefirstdial-uptelephonewillreplacethemanualcallsystemoftheexchange.Thedialdevicewasinstalledin1927,anditwasactuallyusedin1978.

1927---ACpowerringingphone

ManufacturedbyKristianKirksTelefonfabrikkerinHorsens,Denmark,andstillinuseinthe1970s.

1929---Automaticwallphone

Theinformationisunknown.

1930---D-30semi-automaticgold-platedphone

ThisphonewasmanufacturedbyaDanishcompanyin1930.ItsspecialfeatureisthesurfaceGold-plated,whilemostphonesatthetimewerepitchblack,andthisphonehadadialingdevice.

1930---FL-30automatictelephone

MadeinDenmarkinthe1930s,itusesletterstodial.Similarphoneshavebeenusedforabout48years.

1935---Automatictelephone

Thistelephonewasusedtocommunicatewithtelecomexchangesinremoteareas.ItsdesignwasinfluencedbytheUnitedStatesinthe1930s.Theinfluenceofthetelephoneindustry.

1943---CB-43phone

ThisphoneismadeinDenmarkbyKristianKirksTelefonfabrikker,andithastworingtonesdesignedinside,Usedtodistinguishcallsfrominsideandoutsidethecity.

1951---F-51automaticdialphone

ThisphonewasmadebyKristianKirksTelefonfabrikkerafterWorldWarII.

1952---F-52automaticdialtelephone

Manufacturedin1952,itisdifferentfromtheblackbakelitematerialinthepast,itismadeofivoryandMadeofplasticmaterialsthatappearedlater.

1956---"Ericofon"Automaticdialphone

ThisphonewasdesignedandmanufacturedbyLMEricsson,Sweden.NamedEricofon.Itismadeofnewmaterialsandismuchlighterthantraditionaltelephonehandsets.

1968---F-68automaticdialingphone

Thisphonewasthemostcommonphoneinthe1970s.ItwasoriginallydesignedtoIntheten's,itwaswidelymanufacturedinDenmark.

1970---F-68buttondialphone

ThefirstbuttonphoneusedinDenmark,thisphoneusesnumberbuttonsinsteadoftheoriginaldialWay.

1976---76E/DK80pushbuttondialtelephone

ItwasoriginallymanufacturedbyJutlandTelephoneCompanyin1972.

1979---F-79buttondial-typebillingtelephone

Thistelephoneisbetweenordinarytelephonesandpublictelephones.ItmainlyUsedinserviceplaces,hotelsandothersimilarplaces,itcanpreventtheftandmakephonecalls.In1980,DA-80push-buttondialtelephone

Thedesignofthistelephonemarkedtherealentryofthetheoryofelectronicsintothetelephoneindustry.

1982---PortableTelegraphPhone

ThisphonewasmanufacturedbyEricssonWirelessSystem.Atthattime,itcouldonlybeusedinDenmark,Finland,NorwayandUsedinSwedenandothercountries,itsappearancehasopenedupnewhorizonsforthefutureGSMmobilephonesystem.

1983---DanMark2pushbuttonphone

DanMark2wasmanufacturedin1983andistheembodimentofthemostadvancedtechnologyinthe1980s.Ithasmanyfunctions,suchasphonenumbermemoryfunction,redialfunction,monitoringfunction,24kindsofringtones.

In1879,atelegraphlinewaserectedbetweenTianjinandDaguBeitangFort.

OnFebruary21,1882,theNorthTelegraphCompanyofDangaoUniversityestablishedatelephoneexchangeontheBundinShanghai.

In1895,theRussianPopovandtheItalianMarconirespectivelyinventedthewirelesstelegraph.

OnMay18,1897,MarconisucceededinradiocommunicationacrosstheBristolChannel.

In1900,theShanghai-NanjingTelegraphBureauopenedlocaltelephones.Atthattime,therewereonly16telephones.

In1901,MarconirealizedradiocommunicationacrosstheAtlanticOcean.

In1903,thewirelesstelephonetestwassuccessful.

OnNovember8,1907,theFrenchinventorEdwardBellinperformedhisresearchanddevelopment-photofaxinthebuildingoftheFrenchPhotographicSociety.

In1919,PalmandBellanderinventedthe"crossbarconnector".Tenyearslater,Sundsvall,Sweden,builttheworld'sfirstlarge-scalecrossbartelephoneoffice.

InJuly1920,ChunghwaPostlaunchedthepostandtelegraphservice.

In1937,theEnglishmanReevesproposedamethodoftransmittingvoiceinformationwithallcombinationsofpulses(pulsecodemodulation).

InOctober1945,theBritishACClarkproposedtheideaof​​geostationarysatellitecommunication.

In1946,EckertandMochileybuilttheworld'sfirstelectroniccomputer.

In1947,BellLabsoftheUnitedStatesproposedtheconceptofcellularcommunication,dividingtheserviceareaof​​amobilephoneintoseveralcells,andeachcellsetupabasestationtoformacellularmobilecommunicationsystem.

InDecember1950,thelong-distanceopenlineinternationaltrunklineprojectinNortheastChinawascompleted,andthecablecarriercircuitfromBeijingtoMoscowwasopened.

InJuly1954,theU.S.Navyusedthereflectionofradiowavesonthesurfaceofthemoontoconductatransmissiontestoftelephonesintwoplacesontheearth.Andin1956,acommunicationbusinesswasestablishedbetweenWashingtonandHawaii.

In1956,telephonecableswerelaidontheseabedoftheAtlanticOceanbetweenBritainandCanada,makingtelephonecommunicationbetweenlong-distancecontinentsareality.

OnOctober4,1957,theformerSovietUnionsuccessfullylaunchedthefirstartificialsatellite"Satellite1".

InAugust1958,thefirstdomestic12-carriertelephoneequipmentwassuccessfullydevelopedinShanghaiPostandTelecommunicationsEquipmentFactory.

InJanuary1960,China'sfirstsetof1,000crossbarautomatictelephoneexchangeswasopenedinShanghaiWusongTelephoneExchange.

In1960,theAmericanphysicistMaymanusedpowerfulordinarylighttoshineonartificialgems,creatingalaserthatwas10milliontimesstrongerthansunlight.

In1962,theUnitedStatessuccessfullyresearchedpulsecodemodulationequipmentformultiplexedtelephonecommunications.

In1965,thefirstprogram-controlledtelephoneexchangecontrolledbyacomputercameoutintheUnitedStates,markingthebeginningofaneweraoftelephone.

In1966,theBritish-ChineseGaoKunproposedtheideaof​​usingglassfiberforlong-distancelasercommunication.

In1969,BeijingLong-distanceTelecommunicationsBureausuccessfullyinstalledChina'sfirstfullyautomaticlong-distancetelephoneequipment.

In1969,theUSDepartmentofDefenseAdvancedResearchProjectsAgency(ARPA)putforwardaplantodevelopARPAnetwork,whichwascompletedandputintooperationin1969,markingthedevelopmentofcomputercommunicationhasenteredanewera.

In1970,theworld'sfirstprogram-controlleddigitalexchangewasopenedinParis,France,whichmarkedthefullutilityofdigitaltelephonesandthearrivalofaneweraofdigitalcommunications.

In1972,theInternationalTelegraphandTelephoneConsultativeCommittee(CCITT)firstproposedtheconceptofIntegratedServicesDigitalNetwork—ISDN.

In1974,theconstructionoftheSino-Japanesesubmarinecablebegan.ThiswasthefirstinternationalsubmarinecablethatChinaparticipatedintheconstruction.

In1975,China'sself-developedcrossbarautomatictelephoneexchangeequipmentpassedthenationalappraisalandbeganmassproduction.

InMarch1976,thefirstlarge-capacitytransmissionsystemdevelopedbyChina,the1,800-channelcoaxialcablecarriersystemwascompletedandputintoproductioninBeijing,Shanghai,andHangzhou,withatotallengthof1,700kilometers.

In1982,EuropeestablishedGSMwiththetaskofformulatingpan-Europeanmobilecommunicationroamingstandards.

In1982,China'sfirstbatchofcoin-operatedpublictelephonesappearedintheprosperousstreetsofEastandWestChang'anAvenueinBeijing,with22coin-operatedpublictelephoneboothsintotal.

InDecember1982,thefirst10,000-doorprogram-controlledlocaltelephoneexchangesystemintroducedfromJapanwasputintooperationintheFuzhouTelecomBureau,andthefirstprogram-controlledtelephoneofficeintroducedinChinawasbuilt.

In1983,theAMPScellularsystemwasopenedinChicago,USA.

Thefirstfixed-linesmartphoneCOM2008wasborninChina

In2002,thefirstfixed-linesmartphoneCOM2008wasborninChinaAndcarriedoutmassproduction.

ThistypeoftelephonewaslaterofficiallycollectedbytheChinaTelecomMuseum.TherelevantpersoninchargeoftheTelecomMuseumcommentedatthattime:"Ordinaryphonescanonlycommunicatewithvoice,whilebusinesssmartphonescannotonlycommunicatesmoothlywithvoice,butalsointegratemobilephones,PDAs,computers,etc.(businessoffice)Itfunctionsasaninformationreceivingterminal.Atthesametime,ithasthecharacteristicsofalargescreen,handwritingfunction,networkfunctionandotherbusinessphones.ThemostfancyoftheTelecomMuseumisthelatestdevelopmentinthefieldoftelecommunicationsandcommunicationsdisplayedbythisbusinesssmartphone.CollectthisphoneThereisacertainvalueforstudyingandunderstandingthedevelopmentofChina'stelecommunicationsindustry,andweexpectthatnotonlyofficephoneswillbereplacedbybusinesssmartphonesinthefuture,butalsoallfixed-linephoneswilldevelopinthisdirection."

In2006,theA7688seriesofmultimediasmartphones

Thisseriesoffixedtelephonesaddednetworkinterfaces,bringingfixednetworktelephonesintotheeraofmultimedianetworkinformation.Multimediasmartphonewithcolorscreen