Domov Technika Anténní zesilovač

Anténní zesilovač



Úvod

O AntennaAmplifier

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.

Kritéria pro posuzování předností

Za prvé, signál a hluk by měly být malé

Zadruhé, citlivost by měla zůstat zachována

Třetí by mělo být lepší ve voděodolnosti

Čtyři objemy menší

Fivemetalshellje lepší

Šest úspory energie

Sevenwiring je pohodlný

Velmi známá značkah2>

Zámoří: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.

Samozřejmě, že existují některé domácí značky, které mohou dosáhnout této kvality.

Tento článek je ze sítě, nereprezentuje pozici této stanice. Uveďte prosím původ dotisku
HORNÍ