Esittely
Tietoja AntennaAmplifieristä
AntennaamplifierisgenerallycalledMastheaderAmplifierinEnglish,anditisalsocalledPre-amplifierorAntennaAmplifier,Amplificador,etc.insomeEuropeanandAmericancountries.UHF,broadband,lownoiseamplifierbetweenantennaandfeeder.TocompensateforthelossofthetransmissiondistancebetweentheantennaandtheTV,andtoensurethatthedistributorobtainsthenecessaryinputpowerinthesharedantennasystem.
Whenwereceivelong-distanceTVprogramsorterrestrialhigh-definitionTVprograms,theTVsignalisgenerallyweak.Atthistime,weneedtouseamulti-unitTVantennawithstrongdirectivityandhighgain,andtheantennaSetitupashighaspossibleandinanopenplace.Ifyoufeelthatthereceivingsituationisnotidealenough,youneedtoinstallanantennaamplifierbetweentheantennaandtheTVtoincreasethereceivingsensitivity,sothattheTV’simageisstableandthesoundisgood.
Afterusingtheantennaamplifier,itislikeaddinga"telescope"totheTV.ItcanamplifytheweakTVsignalreceivedbytheantenna,butofcourse,intheprocessofreceiving,morethanjustamplifyingIt'saTVsignal,anditalsoincludesallkindsofnoiseandinterference.UsuallyundertheantennaamplifiercanamplifytheTVsignaltotentimesormore.Theantennaamplifierisactuallyasuperhigh-bandamplifier.Thereceivingchannel,frequencyrangeandoverallgainofvarioustypesofantennaamplifiersaredifferent.
Payattentiontotheproblem
(1)PayattentiontotheinstallationpositionTheantennaamplifierusuallyconsistsoftwoparts:theamplifyingpartandthepowersupply.Whentheantennafeederlineisshort(generallyreferstotheuseofindoorantennas),theantennaamplifiercanbeplacednexttotheTV;whentheantennaissetuphigherandthefeederlineislonger,thetwopartsshouldbeplacedseparately,andtheamplifyingpartshouldbesealedbyawaterproofboxLater,itisbesttoinstallitattheendofthesupportrod1~1.5mawayfromtheantennaelement,andthepowersupplypartcanbeplacedneartheTV,whichcanimprovethesignal-to-noiseratiooftheTVsignal.
(2)Channelsmustmatch.Antennaamplifiersaregenerallydividedintotwocategories:VHFandUHF.TheVHFtypecanamplifytheTVsignalofchannels1to12,andtheUHFtypecanamplifytheTVsignalofchannels13to68.Wheninuse,theantennaamplifiershouldmatchtheTVchanneltobereceived.
(3)PayattentiontoimpedancematchingTheoutputimpedanceoftheantennaamplifierandtheoutputendoftheantennaandtheinputimpedanceoftheTVshouldallmatch.Thefeedershouldnotbetoolong,thatistosay,theantennashouldnotbeerectedtoohighortoofar.Otherwise,althoughtheantennaamplifierisaddedtotheTV,theincreasedsignalwillbeseverelyattenuatedduringthetransmissiontotheTV,resultinginlittleimprovementinthereceivingeffect.Inaddition,theinputandoutputfeedlinesoftheantennaamplifiercannotoverlaporbetooclosetoavoidfeedbackorinterference.
(4)Thegainmustbeselected.Thegainofvarioustypesofantennaamplifiersisdifferent,generallytherearehighandlowpoints.High-gainantennaamplifiersusuallyhaveagainof30to60dB,andinconjunctionwithamulti-channelYagiantenna,theycanreceiveTVprogramshundredsofkilometersaway.Thelow-gainantennaamplifierhasagainof20-40dBandcanreceiveprogramsdozensofkilometersaway.Itisnecessarytomakeaproperchoicewhenchoosing,butitisnotthatthehigherthegain,thebetter.
(5)Checktheinstallationeffect.Iftheimagereceivedbytheindoorcableispoor,andgoodresultscanbeobtainedwheninstallinganoutdoorantenna,youcanstillusetheindoorantennaafterusingtheamplifier.Ifafterinstallingtheantennaamplifier,theTVviewingeffectdoesnotchangesignificantly,ortheviewingeffectisworsethanbefore,itiscausedbyaninstallationerror,andyoushouldcheckitcarefullybeforecorrectingitaccordingtothecorrectinstallationmethod.
(6)Goodantennasandlightningprotectionequipment,suchasTVuserswhouseoutdoorantennas,needtoinstallanantennaamplifier,andagoodmulti-elementantennamustbeusedtocooperatewithit,andlightningprotectionequipmentmustbeinstalledtopreventLightningstrikes.
Ansioiden arviointiperusteet
Ensinnäkin signaalin ja melun tulisi olla pieni
Toiseksi herkkyyden pitäisi olla korkea
Kolmannen pitäisi olla parempi vedenkestävyys
Neljä tilavuutta pienempi
Viisimetallikuorinen parempi
Kuusi virransäästöä
Seitsemän johtoa on kätevä
Tunnettu brandh2>
Ulkomailla:Antiference,Global,Johansson,Fracarro,Fringe,Ikusi,IkusiLabgear,Maxview,Paragon,Philex,Proception,Televes,Triax,Vision,Wolsey
ButmostoftheaboveproductsaremainlyProducedinSoutheastAsia,especiallyinChina.
Domestic:Boligo,Seebest,Wanshida,Wanshibao,Jiaxun
ThesebrandsarealsotheOEMsofmanyforeignbrands,andsomeofthebrands'productqualitycanbestraightforward.Referstofirst-lineforeignbrands.
Architecturediagram
Thisillustrationtellstheuserhowtoconnectfromtheantennatotheamplifiertothepowersupplytotheuser.Butthislegendisnotclearenough.Becausetheantennaamplifierisalsocalledpreamplifier,itisbecausetheantennaamplifierisinstalledlessthan30cmbelowtheantenna,andthegeneralpowersupplywillbeinstallednexttotheTV,sothatthesignallinecanbedirectlyinsertedintotheTV.IfmultipleTVsreceiveaprogramononeantenna,thepowersupplyisgenerallyplacednearthebranchdistributor.Asforwhethertowatchhigh-definitionTVprogramsoranalogprograms,itdependsontheconfigurationofyourTV.Atpresent,mid-to-high-endflat-panelTVshavebuilt-interrestrialhigh-definitionset-topboxmodules,someofwhicharecalledall-in-ones,andthetechnologyisverymature.Comparedwithbroadcastandtelevisionsignals,terrestrialhigh-definitionprogramsarefree,andtheinitialinstallationcostisrelativelylow.Aslongasyouchoosehigh-qualityantennasandantennaamplifiers,youcanreceiveultra-high-definitionprogramsinmpg-2orevenmpg-4format.
Applicationexample
Inthisexample,themostbasicequipmentsuchasthehomeantennaamplifier7322andbranchdistributorofJohanssoninBelgiumareused.TheEuropeantestreportindicatedthatHDTVcanbereceivedinopenconditions,evenifitisonthesideofthehighway,closetothemobilebasestationorSanyin,etc.,itcanstillachieveaclearervideosignal,withidealgainandanti-interference.,Especiallyintermsofanti-mobilesignalinterference,itisworthyofrecognition.DirectTV,theworld'slargestproviderofsatelliteTVlivebroadcastsandterrestrialhigh-definitionprograms,iscooperatingwiththisbrand.
Tietenkin on olemassa joitakin kotimaisia merkkejä, jotka voivat saavuttaa tämän laadun.