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  • ProjectGutenberg'sTheRadioAmateur'sHandBook,byA.FrederickCollins

    ThiseBookisfortheuseofanyoneanywhereatnocostandwithalmostnorestrictionswhatsoever.Youmaycopyit,giveitawayorre-useitunderthetermsoftheProjectGutenbergLicenseincludedwiththiseBookoronlineatwww.gutenberg.org

    Title:TheRadioAmateur'sHandBook

    Author:A.FrederickCollins

    PostingDate:March21,2013[EBook#6934]ReleaseDate:November,2004FirstPosted:February13,2003

    Language:English

    ***STARTOFTHISPROJECTGUTENBERGEBOOKTHERADIOAMATEUR'SHANDBOOK***

    ProducedbyAlanMillarandtheOnlineDistributedProofreadingTeam.

    THERADIOAMATEUR'SHANDBOOK

    PhotographunavailableA.FrederickCollins,InventoroftheWirelessTelephone,1899.AwardedGoldMedalforsame,

    AlaskaYukonPacificExposition,1909.

    THERADIOAMATEUR'SHANDBOOKAComplete,AuthenticandInformativeWorkonWirelessTelegraphyandTelephony

    BYFREDERICKCOLLINS

    InventoroftheWirelessTelephone1899;HistorianofWireless1901-1910;Authorof"WirelessTelegraphy"1905

    1922

    TOWILLIAMMARCONI

    INVENTOROFTHEWIRELESSTELEGRAPH

  • INTRODUCTION

    Beforedelvingintothemysteriesofreceivingandsendingmessageswithoutwires,awordastothehistoryoftheartanditspresentdayapplicationsmaybeofservice.Whilepopularinterestinthesubjecthasgoneforwardbyleapsandboundswithinthelasttwoorthreeyears,ithasbeenamatterofscientificexperimentformorethanaquarterofacentury.

    ThewirelesstelegraphwasinventedbyWilliamMarconi,atBologna,Italy,in1896,andinhisfirstexperimentshesentdotanddashsignalstoadistanceof200or300feet.ThewirelesstelephonewasinventedbytheauthorofthisbookatNarberth,Penn.,in1899,andinhisfirstexperimentsthehumanvoicewastransmittedtoadistanceofthreeblocks.

    ThefirstvitalexperimentsthatleduptotheinventionofthewirelesstelegraphweremadebyHeinrichHertz,ofGermany,in1888whenheshowedthatthesparkofaninductioncoilsetupelectricoscillationsinanopencircuit,andthattheenergyofthesewaveswas,inturn,sentoutintheformofelectricwaves.Healsoshowedhowtheycouldbereceivedatadistancebymeansofaringdetector,whichhecalledaresonator.

    In1890,EdwardBranly,ofFrance,showedthatmetalfilingsinatubecoheredwhenelectricwavesactedonthem,andthisdevicehetermedaradioconductor;thiswasimproveduponbySirOliverLodge,whocalleditacoherer.In1895,AlexanderPopoff,ofRussia,constructedareceivingsetforthestudyofatmosphericelectricity,andthisarrangementwastheearliestonrecordoftheuseofadetectorconnectedwithanaerialandtheearth.

    Marconiwasthefirsttoconnectanaerialtoonesideofasparkgapandagroundtotheothersideofit.Heusedaninductioncoiltoenergizethesparkgap,andatelegraphkeyintheprimarycircuittobreakupthecurrentintosignals.AddingaMorseregister,whichprintedthedotanddashmessagesonatape,tothePopoffreceptorheproducedthefirstsystemforsendingandreceivingwirelesstelegraphmessages.

    PhotographunavailableCollins'WirelessTelephoneExhibitedattheMadisonSquareGarden,October1908.

    AfterMarconihadshowntheworldhowtotelegraphwithoutconnectingwiresitwouldseem,onfirstthought,tobeaneasymattertotelephonewithoutwires,butnotso,fortheelectricsparksetsupdampedandperiodicoscillationsandthesecannotbeusedfortransmittingspeech.Instead,theoscillationsmustbeofconstantamplitudeandcontinuous.ThatadirectcurrentarclighttransformsapartofitsenergyintoelectricoscillationswasshownbyFirthandRogers,ofEngland,in1893.

    Theauthorwasthefirsttoconnectanarclampwithanaerialandaground,andtouseamicrophonetransmittertomodulatethesustainedoscillationssosetup.Thereceivingapparatusconsistedofavariablecontact,knownasapill-boxdetector,whichSirOliverLodgehaddevised,andtothiswasconnectedanEricssontelephonereceiver,thenthemostsensitivemade.Alaterimprovementforsettingupsustainedoscillationswastheauthor'srotatingoscillationarc.

    Sincethosememorabledaysofmorethantwodecadesago,wonderfuladvanceshavebeenmadein

  • bothofthesemethodsoftransmittingintelligence,andtheendisasyetnowhereinsight.Twelveorfifteenyearsagotheboysbegantogetfunoutoflistening-intowhattheshipandshorestationsweresendingand,further,theybegantodoalittlesendingontheirownaccount.Theseyoungsters,whocausedtheprofessionaloperatorsmanyapang,werethefirstwirelessamateurs,andamongthemexpertsweredevelopedwhoareforemostinthepracticeofthearttoday.

    Awaybackthere,thesparkcoilandthearclampweretheonlyknownmeansforsettinguposcillationsatthesendingend,whiletheelectrolyticandcrystaldetectorsweretheonlyavailablemeansfortheamateurtoreceivethem.Asitwasnexttoimpossibleforaboytogetacurrenthavingahighenoughvoltageforoperatinganoscillationarclamp,wirelesstelephonywasoutofthequestionforhim,sohehadtosticktothesparkcoiltransmitterwhichneededonlyabatterycurrenttoenergizeit,andthis,ofcourse,limitedhimtosendingMorsesignals.Astheelectrolyticdetectorwascumbersomeandrequiredaliquid,thecrystaldetectorwhichcameintobeingshortlyafterwasjustassensitiveandsoondisplacedtheformer,evenasthishaddisplacedthecoherer.

    Afewyearsaheadoftheseamateurs,thatistosayin1905,J.A.Fleming,ofEngland,inventedthevacuumtubedetector,buttenmoreyearselapsedbeforeitwasperfectedtoapointwhereitcouldcompetewiththecrystaldetector.Thenitsusebecamegeneralandworkerseverywheresoughtto,anddidimproveit.Further,theyfoundthatthevacuumtubewouldnotonlyactasadetector,butthatifenergizedbyadirectcurrentofhighvoltageitwouldsetupsustainedoscillationslikethearclamp,andthevalueofsustainedoscillationsforwirelesstelegraphyaswellaswirelesstelephonyhadalreadybeendiscovered.

    Thefactthatthevacuumtubeoscillatorrequiresnoadjustmentofitselements,thatitsinitialcostismuchlessthantheoscillationarc,besidesotherconsiderations,isthereasonthatitpopularizedwirelesstelephony;andbecausecontinuouswaveshavemanyadvantagesoverperiodicoscillationsisthereasonthevacuumtubeoscillatorisreplacingthesparkcoilasawirelesstelegraphtransmitter.Moreover,byusinganumberoflargetubesinparallel,powerfuloscillationscanbesetupand,hence,thewavessentoutareradiatedtoenormousdistances.

    WhileoscillatortubeswerebeingexperimentedwithintheresearchlaboratoriesoftheGeneralElectric,theWestinghouse,theRadioCorporationofAmerica,andotherbigcompanies,alltheyouthfulamateursinthecountryhadlearnedthatbyusingavacuumtubeasadetectortheycouldeasilygetmessages500milesaway.Theuseofthesetubesasamplifiersalsomadeitpossibletoemployaloudspeaker,sothataroom,ahall,oranout-of-dooraudiencecouldhearclearlyanddistinctlyeverythingthatwasbeingsentout.

    Theboyamateurhadonlytoletfatherormotherlisten-in,andtheyweredulyimpressedwhenhetoldthemtheyweregettingitfromKDKA(thePittsburghstationoftheWestinghouseCo.),forwasnotPittsburgh500milesaway!Andsothey,too,becameenthusiasticwirelessamateurs.Thisnewinterestofthegrown-upswasatoncemetnotonlybythemanufacturersofapparatuswithcompletereceivingandsendingsets,butalsobythebigcompanieswhichbeganbroadcastingregularprogramsconsistingofmusicandtalksonallsortsofinterestingsubjects.

    Thisisthewireless,orradio,astheaverageamateurknowsittoday.Butitisbynomeansthelimitofitspossibilities.Onthecontrary,wearejustbeginningtorealizewhatitmaymeantothehumanrace.TheGovernmentisnowutilizingittosendoutweather,cropandmarketreports.Foreigntradeconditionsarebeingreported.TheNavalObservatoryatArlingtoniswirelessingtimesignals.

  • Departmentstoresarebeginningtoissueprogramsandadvertisebyradio!Citiesarealsotakingupsuchprograms,andtheywilldoubtlessbeincludedsoonamongtheregularprivilegesofthetax-payers.Politiciansaddresstheirconstituents.Preachersreachthestay-at-homes.Greatsingersthrillthousandsinsteadofhundreds.Soonitwillbepossibletohearthefinestmusicalprograms,entertainers,andorators,withoutbudgingfromone'seasychair.

    IntheWorldWarwirelessprovedofinestimablevalue.Airplanes,insteadofflyingaimlessly,keptinconstanttouchwithheadquarters.Bodiesoftroopsmovedalertlyandintelligently.Shipsatseatalkedfreely,overhundredsofmiles.Scoutsreported.Everywhereitsinvisibleaidwasinvoked.

    Intimeofpeace,however,ithasprovedandwillprovethegreatestservantofmankind.Wirelessmessagesnowgodailyfromcontinenttocontinent,andsoonwillgoaroundtheworldwiththesamefacility.Shipsindistressatseacansummonaid.Vesselseverywheregettheday'snews,eventobaseballscores.Dailynewtasksarebeingassignedthistireless,wirelessmessenger.

    Messageshavebeensentandreceivedbymovingtrains,theLackawannaandtheRockIslandrailroadsbeingpioneersinthisfield.Messageshavealsobeenreceivedbyautomobiles,andoneinventorhassuccessfullydemonstratedamotorcarcontrolledentirelybywireless.Thismethodofcommunicationisbeingemployedmoreandmorebynewspapers.Itisalsoofgreatserviceinreportingforestfires.

    Collegesarebeginningtotakeupthesubject,someofthefirstbeingTuftsCollege,HunterCollege,Princeton,Yale,Harvard,andColumbia,whichhaveregularlyorganizeddepartmentsforstudentsinwireless.

    Insteadoftheunwieldyandformidablelookingapparatusofashorttimeago,experimentersarenowvyingwitheachotherinmakingsmallornovelequipment.Portablesetsofallsortsarebeingfashioned,fromonewhichwillgointoanordinarysuitcase,toonesosmallitwilleasilyslipintoaBrowniecamera.Onereceiverdepictedinanewspaperwasoneinchsquare!Anotherwasaringforthefinger,withasettingoneinchbyfive-eighthsofaninch,andanumbrellaasa"ground."Walkingsetswithreceiversfastenedtoone'sbeltarealsocommon.Dailynewnoveltiesandmarvelsareannounced.

    Meanwhile,theradioamateurtowhomthisbookisaddressedmayhavehisshareinthejoysofwireless.Togetallofthesegoodthingsoutoftheetheronedoesnotneedarodoragun--onlyacopperwiremadefastateitherendandareceivingsetofsomekind.Ifyouareasheerbeginner,thenyoumustbeverycarefulinbuyingyourapparatus,forsincethegreatwaveofpopularityhaswashedwirelessintotheheartsofthepeople,numerouscompanieshavesprungupandsomeofthesearesellingtheveriestkindsofjunk.

    Andhow,youmayask,areyougoingtobeabletoknowthegoodfromtheindifferentandbadsets?Bybuyingamakeofafirmwithanestablishedreputation.Ihavegivenafewoffhandattheendofthisbook.Obviouslytherearemanyothersofmerit--somany,indeed,thatitwouldbequiteimpossibletogetthemallinsuchalist,butthesewillserveasaguideuntilyoucanchooseintelligentlyforyourself.

    F.C.