Ma Cable TV network kwa ana aang'ono. Gawo 6: RF Signal Amplifiers

M'nkhaniyi tiwona ma amplifiers apamwamba kwambiri a wailesi ya kanema pagawo la coaxial la mzere.

Zamkatimu zankhani

• Gawo 1: Zomangamanga zonse za netiweki ya CATV
• Gawo 2: Mapangidwe ndi mawonekedwe a wave
• Gawo 3: Chigawo cha analogi cha chizindikiro
• Gawo 4: Digital gawo la chizindikiro
• Gawo 5: Coaxial Distribution Network
• Gawo 6: RF Amplifiers
• Gawo 7: Optical Receivers
• Gawo 8: Optical backbone network
• Gawo 9: Mutu
• Gawo 10: Troubleshooting pa chingwe TV maukonde

Ngati m'nyumba muli cholandira chimodzi chokha (kapena ngakhale mu chipika chonse) ndipo mawaya onse okwera amapangidwa ndi chingwe cha coaxial, kukulitsa chizindikiro kumafunika pachiyambi. Mu maukonde athu, timagwiritsa ntchito kwambiri zida zochokera ku Teleste, chifukwa chake ndikuwuzani kugwiritsa ntchito chitsanzo chawo, koma makamaka, zida zochokera kwa opanga ena sizosiyana ndipo magwiridwe antchito amasinthidwe nthawi zambiri amakhala ofanana.

Mtundu wa CXE180M uli ndi zosintha zochepa:


Monga mukukumbukira m'magawo am'mbuyomu, chizindikiro chili ndi magawo awiri ofunikira: mulingo ndi malo otsetsereka. Ndiwo omwe angathandize kukonza makonzedwe amplifier. Tiyeni tiyambe mu dongosolo: mwamsanga pambuyo cholumikizira cholowera pali attenuator. Zimakuthandizani kuti muchepetse chizindikiro cholowera mpaka 31 dB (pamene jumper yabuluu ikasinthidwa molingana ndi chithunzi, mizere ya mfundo imasintha kuchokera 0-15 mpaka 16-31 dB). Izi zitha kukhala zofunikira ngati amplifier ilandila chizindikiro chopitilira 70 dBµV. Chowonadi ndi chakuti gawo la amplifier limapereka kuchuluka kwa siginecha ndi 40 dB, ndipo pazotulutsa sitiyenera kuchotsa zosaposa 110 dBµV (pamlingo wapamwamba chiŵerengero cha ma signal-to-phokoso chikutsika kwambiri ndipo chiwerengerochi ndi choyenera ma amplifier onse a Broadband ndi olandila okhala ndi amplifier yomangidwa) . Chifukwa chake, ngati 80 dBµV ifika pakulowetsa kwa amplifier, mwachitsanzo, pazotulutsa idzatipatsa 120 dBµV yaphokoso ndi manambala amwazikana. Kuti mupewe izi, muyenera kuyika chothandizira kuti chikhale chotsitsa cha 10 dB.

Kumbuyo kwa attenuator tikuwona wofanana. Ndikofunikira kuthetsa kupendekera kobwerera, ngati kulipo. Izi zimatheka pochepetsa kuchuluka kwa ma siginecha kumalo otsika pafupipafupi mpaka 20 dB. Ndikoyenera kudziwa kuti sitingathe kuthetsa otsetsereka pokweza kuchuluka kwa ma frequency apamwamba, kumangopondereza otsika.

Zida ziwirizi nthawi zambiri zimakhala zokwanira kukonza zopatuka zazing'ono zachizindikiro kuchokera pachizoloŵezi. Ngati izi siziri choncho, mutha kugwiritsa ntchito zotsatirazi:

Woyeseza chingwe, yopangidwa mwa mawonekedwe oyikapo omwe amatha kuikidwa molunjika kapena molunjika, monga momwe dzinalo limatanthawuzira, amafananiza kuphatikizidwa kwa gawo lalitali la chingwe, pomwe kuchepetsedwa kwakukulu kwa ma frequency apamwamba amtunduwu kuyenera kuchitika. Izi zimakuthandizani kuti muchepetse kutsetsereka kwachindunji ngati kuli kofunikira, kupondereza 8 dB pamalo okwera pafupipafupi. Izi zitha kukhala zothandiza mukayika ma amplifiers mu cascade patali pang'ono, mwachitsanzo.

Pambuyo paziwonetserozi, chizindikirocho chimadutsa gawo loyamba la gawo la amplifier, pambuyo pake timawona kuyika kwina, komwe kumatithandiza kuchepetsa kupindula. Chodumphira chotsatira chidzatithandizanso kupondereza ma frequency otsika kuti tipeze malo otsetsereka. Zokonda ziwirizi ndizofanana kwenikweni ndi chowongolera ndi chofananira, koma kugwira ntchito ndi gawo lachiwiri la cascade.

Pakutulutsa kwa gawo la amplifier tikuwona test tap. Ichi ndi cholumikizira cholumikizira chomwe mungalumikizireko chida choyezera kapena cholandirira kanema wawayilesi kuti muwunikire mtundu wa chizindikirocho. Sizida zonse ndipo pafupifupi palibe ma TV omwe amatha kukonza bwino chizindikiro chokhala ndi dBµV zana kapena kuposerapo, chifukwa chake zoyeserera pazida zilizonse zimapangidwa nthawi zonse ndi 20-30 dB kuchokera pamtengo weniweni. Izi ziyenera kukumbukiridwa nthawi zonse potenga miyeso.

Choyika china chimayikidwa musanatuluke. Chithunzi cha amplifier chikuwonetsa kuti muvi womwe wawonetsedwa pamenepo umalozera ku terminal yolondola. Ndipo izi zikutanthauza kuti sipadzakhala chizindikiro kumanzere. Kuyika kotereku kumaphatikizidwa mu amplifiers awa "kunja kwa bokosi", ndipo mkati mwa bokosi lokha pali chinanso chophatikizidwa muzoperekera:

Zimakupatsani mwayi wogwiritsa ntchito chotulutsa chachiwiri, koma mosakayikira zimabweretsa kutsika kwa 4 dB.

Poyang'ana koyamba, mtundu wa amplifier CXE180RF uli ndi zokonda kuwirikiza kawiri:


M'malo mwake, zonse sizowopsa: kupatula kusiyana kwakung'ono, zonse apa ndizofanana ndi zomwe takambirana pamwambapa.

Choyamba, pompu yoyesera idawonekera pazolowetsa. Zimafunika kuwongolera siginecha popanda kulumikiza chingwe kuchokera pazolowetsa amplifier ndipo, molingana ndi izi, popanda kusokoneza kuwulutsa.

Kachiwiri, zosefera zatsopano za diplex, komanso zotulutsa zotulutsa ndi zofananira, ndizofunikira pakukhazikitsa njira zotumizira za DOCSIS, chifukwa cha nkhaniyi ndingonena kuti zosefera zimadula ma frequency omwe awonetsedwa ndipo izi zitha. kukhala vuto ngati mu ma sipekitiramu ma sipekitiramu TV mayendedwe amawulutsidwa pa ma frequency awa. Mwamwayi, wopanga amawapanga ndi zinthu zosiyanasiyana ndikuzisintha ngati kuli kofunikira sikovuta.


Makono (komanso jumper, yomwe imayambitsa kutsika kwa 10 dB) imakhudza njira yobwerera yokha ndipo sangathe kusintha chizindikiro cha kanema wawayilesi.

Koma ma jumper atatu otsalawo amatipatsa kuti tidziŵe ukadaulo monga mphamvu yakutali.

Popanga nyumba, amplifiers nthawi zambiri amaikidwa m'malo omwe pangakhale mavuto ndi magetsi kuchokera kumagulu ogawa. Kuphatikiza apo, plug-socket pair iliyonse, yomwe imaphatikizansopo chowotcha (chomwe chimatha kukhazikitsidwa pamalo osayembekezeka), chimayimira kulephera. Pachifukwa ichi, ndizotheka kugwiritsa ntchito zida zamagetsi mwachindunji kudzera pa chingwe cha coaxial. Kuphatikiza apo, monga momwe zimawonera pazolemba pamagetsi opangira magetsi, zitha kukhala zosintha kapena zachindunji ndi mitundu yayikulu kwambiri yamagetsi. Chifukwa chake: ma jumper atatuwa amathandizira kuthekera kopereka zomwe zikuyenda pakalipano, komanso chilichonse mwazotulutsa ziwirizo padera, ngati tifunikira kupatsa mphamvu amplifier yotsatira mu cascade. Pamene chokwera ndi olembetsa chikutsegulidwa, magetsi sangathe kuperekedwa ku zotsatira, ndithudi!

Ndatchula kale mu m'mbuyomu gawo lomwe pamakina oterowo matepi akuluakulu apadera amagwiritsidwa ntchito:

Amagwiritsa ntchito zinthu zazikulu komanso zodalirika, ndipo thupi lalikulu limapereka kutentha ndi chitetezo.

Gwero lamagetsi pankhaniyi ndi chipika chokhala ndi thiransifoma yayikulu yomangidwa:


Ndikoyenera kunena kuti, ngakhale zikuwoneka kuti njira yabwino yoperekera magetsi akutali, ma amplifiers omwe amagwira ntchito motere sakhala ndi mwayi wopulumuka kulephera kwa magetsi kunyumba popanda zotsatirapo, ndipo powasintha, ogwira ntchito zaukadaulo ayeneranso kuyang'ana ndikuzimitsa. mphamvu ku unit yokha, kuti musagwire ntchito ndi zingwe zamoyo ndipo, motero, Pamene amplifier imodzi yasinthidwa, nyumba yonse imakhalabe popanda chizindikiro. Pazifukwa zomwezo, ma amplifiers amafunikira popi yoyeserera pakulowetsa: apo ayi muyenera kugwira ntchito ndi chingwe chamoyo.

Zingakhale zosangalatsa kudziwa kuchokera kwa anzako momwe machitidwe omwe ali ndi magetsi akutali alili, lembani mu ndemanga ngati muwagwiritsa ntchito, chonde.

Ngati mukufuna kulumikiza ma TV ambiri mkati mwa nyumba kapena ofesi, mukhoza kukumana ndi kusowa kwa msinkhu pambuyo pa mndandanda wa ogawa. Pankhaniyi, ndikofunikira kukhazikitsa amplifier pamalo olembetsa, pomwe zida zazing'ono zokhala ndi zoikamo zochepa komanso mulingo wocheperako zimagwiritsidwa ntchito.
Mwachitsanzo, monga chonchi:


Source: www.habr.com