Kulesi sihloko sizobheka ama-amplifiers esignali yomsakazo we-high-frequency ye-cable television engxenyeni ye-coaxial yomugqa.
Okuqukethwe ochungechungeni lwezihloko
- Ingxenye 6: Izikhulisi Zesiginali ye-RF
- Ingxenye 7: Abamukeli be-Optical
- Ingxenye 8: Inethiwekhi ye-Optical backbone
- Ingxenye 9: Isihloko
- Ingxenye 10: Ukuxazulula inkinga inethiwekhi ye-CATV
Uma kunesamukeli esisodwa kuphela se-optical endlini (noma ngisho nakuwo wonke ibhulokhi) futhi zonke izintambo ezikhuphukeleni zenziwa ngentambo ye-coaxial, ukukhulisa isignali kuyadingeka ekuqaleni kwazo. Kunethiwekhi yethu, ikakhulukazi sisebenzisa amadivaysi avela ku-Teleste, ngakho-ke ngizokutshela usebenzisa isibonelo sabo, kodwa ngokuyisisekelo, imishini evela kwabanye abakhiqizi ayihlukile futhi isethi yokusebenza yokucushwa ivame ukufana.
Imodeli ye-CXE180M inenani elincane lezilungiselelo:
Njengoba cishe ukhumbula ezingxenyeni ezedlule, isignali inemingcele emibili ebalulekile yobuningi: izinga kanye nomthambeko. Yibo abangasiza ukulungisa izilungiselelo ze-amplifier. Ake siqale ngokulandelana: ngokushesha ngemva kwesixhumi sokufaka kukhona i-attenuator. Ikuvumela ukuthi unciphise isignali yokufaka kuze kufike ku-31 dB (uma i-jumper eluhlaza okwesibhakabhaka ishintshwa ngokuvumelana nomdwebo, ububanzi be-knob bushintsha kusuka ku-0-15 kuya ku-16-31 dB). Lokhu kungase kudingeke uma i-amplifier ithola isignali engaphezu kuka-70 dBΒ΅V. Iqiniso liwukuthi isigaba se-amplifier sihlinzeka ngokukhuphuka kwezinga lesignali ngo-40 dB, futhi ekuphumeni akufanele sisuse ngaphezu kwe-110 dBΒ΅V (ezingeni eliphezulu isilinganiso sesignali-kuya-kumsindo sehla kakhulu futhi lesi sibalo sifanelekile wonke ama-amplifiers e-broadband nabamukeli abane-amplifier eyakhelwe ngaphakathi) . Ngakho, uma u-80 dBΒ΅V efinyelela okokufaka kwe-amplifier, isibonelo, lapho okukhiphayo kuzosinika u-120 dBΒ΅V womsindo nezinombolo ezihlakazekile. Ukuze ugweme lokhu, udinga ukusetha i-attenuator yokufaka endaweni yokudambisa engu-10 dB.
Ngemuva kwe-attenuator sibona isilinganisi. Kuyadingeka ukuqeda ukutsheka okubuyela emuva, uma kukhona. Lokhu kufinyelelwa ngokunciphisa izinga lesignali endaweni yefrikhwensi ephansi ngokufika ku-20 dB. Kuyaphawuleka ukuthi ngeke sikwazi ukuqeda ukuthambekela okuphambene ngokuphakamisa izinga lamafrikhwensi aphezulu, cindezela kuphela aphansi.
Lawa mathuluzi amabili ngokuvamile anele ukulungisa ukuchezuka kwesignali okuncane kokujwayelekile. Uma lokhu kungenzeki, ungasebenzisa okulandelayo:
Isifanisi sekhebula, eyenziwe ngendlela yokufaka engabekwa ivundlile noma iqonde phezulu, njengoba igama lisho, ilingisa ukufakwa kwengxenye ende yekhebula, lapho ukuncishiswa kwamafrikhwensi aphezulu obubanzi kufanele kwenzeke. Lokhu kukuvumela ukuthi unciphise i-slope eqondile uma kunesidingo, ucindezela i-8 dB endaweni yefrikhwensi ephezulu. Lokhu kungaba usizo lapho ufaka izikhulisamazwi ku-cascade ebangeni elifushane, isibonelo.
Ngemva kwalezi zindlela zokukhwabanisa, isignali idlula esigabeni sokuqala sesiteji se-amplifier, ngemva kwalokho sibona enye ifaka, esivumela ukuthi siqhubeke sinciphisa inzuzo. I-jumper eyilandelayo izophinde isisize ukuthi sicindezele amaza aphansi ukuze sithole i-slope edingekayo. Lezi zilungiselelo ezimbili ziyafana ngempela nesibambisi sokufaka nesilinganisi, kodwa zisebenza nesigaba sesibili se-cascade.
Ekuphumeni kwesiteji se-amplifier sibona kampompi wokuhlola. Lesi isixhumi esinentambo evamile ongaxhuma kuso insimbi yokulinganisa noma isamukeli sikamabonakude ukuze ugade ikhwalithi yesiginali yokuphumayo. Akuwona wonke amadivayisi futhi cishe awekho ama-TV akwazi ukucubungula kahle isiginali enezinga le-dBΒ΅V eyikhulu noma ngaphezulu, ngakho imikhondo yokuhlola kunoma iyiphi into esetshenziswayo ihlale yenziwa ngokuncishiswa okungu-20-30 dB kusuka kunani langempela lokuphumayo. Lokhu kufanele kuhlale kukhunjulwa lapho uthatha izilinganiso.
Okunye okufakiwe kufakwa ngaphambi kokuphuma. Isithombe se-amplifier sibonisa ukuthi umcibisholo okhonjiswe kuso ukhomba kuphela ukuphela kwesokudla. Futhi lokhu kusho ukuthi ngeke kube khona isignali ngakwesobunxele. Ukufakwa okunjalo kufakwe kulawa ma-amplifiers "ngaphandle kwebhokisi", futhi ngaphakathi kwebhokisi ngokwalo kukhona okunye okufakwe kusethi yokulethwa:
Ikuvumela ukuthi usebenzise okukhiphayo kwesibili, kodwa ngokuqinisekile yethula ukuncishiswa kwesignali okungu-4 dB.
Uma uthi nhlΓ‘, imodeli ye-amplifier CXE180RF inezilungiselelo eziphindwe kabili:
Eqinisweni, yonke into ayesabi kangako: ngaphandle komehluko omncane, yonke into lapha iyafana naleyo okuxoxwe ngayo ngenhla.
Okokuqala, umpompi wokuhlola uvele kokokufaka. Kudingeka ukulawula isignali ngaphandle kokunqamula ikhebula kokokufaka kwe-amplifier futhi, ngokufanelekile, ngaphandle kokuphazamisa ukusakaza.
Okwesibili, izihlungi ezintsha ze-diplex, kanye ne-attenuator ephumayo kanye ne-equalizer, ziyadingeka ukuze kumiswe iziteshi zokudlulisela ze-DOCSIS, ngakho-ke ngezinjongo zalesi sihloko ngizosho kuphela ukuthi izihlungi zinqamule lezo zikhathi ezikhonjisiwe kuzo futhi lokhu kungakwazi. iba yinkinga uma kumashaneli we-TV we-spectrum yesiginali kusakazwa kulawa mafrikhwensi. Ngenhlanhla, umenzi ukhiqiza ngamanani ahlukene futhi ashintshe uma kunesidingo akunzima.
Ama-knob (kanye ne-jumper, eyethula ukuncishiswa kwe-10 dB) athinta kuphela isiteshi sokubuyisela futhi awakwazi nakancane ukushintsha isignali yethelevishini.
Kodwa ama-jumpers amathathu asele asinikeza ukujwayelana nobuchwepheshe obunjalo amandla akude.
Lapho uklama izindlu, ama-amplifiers avame ukufakwa ezindaweni lapho kungase kube nezinkinga ngokunikezwa kukagesi ovela kumabhodi okusabalalisa. Ukwengeza, i-plug-socket pair ngayinye, ehlanganisa ne-circuit breaker (engase ifakwe endaweni engalindelekile kakhulu), imele iphuzu elingase lihluleke. Kulokhu, kungenzeka ukunika amandla imishini ngokuqondile ngekhebula le-coaxial. Ngaphezu kwalokho, njengoba kungase kubonakale kumaka epuleti lokuphakela amandla, ingaba ijika elishintshayo noma eliqondile elinobubanzi be-voltage ebanzi kakhulu. Ngakho-ke: lawa ma-jumpers amathathu anika amandla ithuba lokuhlinzeka ngokugeleza kwamanje kokokufaka, kanye nakuwo wonke umphumela kokubili ngokwehlukana, uma sidinga ukunika amandla i-amplifier elandelayo ku-cascade. Lapho isikhuphukeli esinababhalisi sivuliwe, i-voltage ayikwazi ukunikezwa kokuphumayo, yebo!
Sengishilo ku ingxenye esetshenziswa ohlelweni olunjalo ompompi abakhulu abakhethekile:
Basebenzisa izakhi ezinkulu nezithembeke kakhulu, futhi umzimba omkhulu uhlinzeka ngokukhipha ukushisa nokuvikela.
Umthombo wamandla kuleli cala uyibhulokhi ene-transformer enkulu eyakhelwe ngaphakathi:
Kuyafaneleka ukusho ukuthi, ngaphandle kokubonakala kukuhle kohlelo lokunikezwa kwamandla okude, ama-amplifiers asebenza ngale ndlela mancane amathuba okuthi akwazi ukusinda ekuhlulekeni kokunikezwa kwamandla ekhaya ngaphandle kwemiphumela, futhi lapho ewashintsha, abasebenzi bezobuchwepheshe kufanele bafune futhi bacime. amandla eyunithi ngokwayo, ukuze ingasebenzi ngezintambo ezibukhoma futhi, ngaleyo ndlela, Uma i-amplifier eyodwa ishintshwa, yonke indlu ihlala ingenasiginali. Ngesizathu esifanayo, ama-amplifiers anjalo adinga ukuthepha ngokuchofoza kokokufaka: ngaphandle kwalokho kuzomele usebenze ngekhebula elibukhoma.
Kungaba mnandi ukwazi kozakwethu ukuthi amasistimu ajwayelekile anamandla akude anjani, bhala kumazwana uma uwasebenzisa, sicela.
Uma udinga ukuxhuma inombolo enkulu yama-TV ngaphakathi kwefulethi noma ihhovisi, ungase uhlangabezane nokuntuleka kwezinga ngemva kochungechunge lwabahlukanisi. Kulokhu, kuyadingeka ukufaka i-amplifier emagcekeni obhalisile, lapho kusetshenziswa amadivayisi amancane anenani eliphansi lezilungiselelo kanye nezinga eliphansi lokukhulisa amandla.
Ngokwesibonelo, kanje:
Source: www.habr.com