Umsakazo ungabonakala njengomlingo, kodwa empeleni kulula ukuwuqonda
Njalo njalo, abanye bethu bahlakulela ukuqonda ukuthi umsakazo we-AM / FM uzizwa unjengomlingo omsulwa. Uma ushintsha umsakazo, ungazwa umculo, izwi, noma yikuphi ukuzijabulisa komsindo okusakazwa emthonjeni otholakala emakhulu - noma ngisho nezinkulungwane - amamayela kude! Ngokudabukisayo, akuyona imilingo ngempela. Eqinisweni, ukwamukela umsakazo kulula kakhulu ukuyiqonda uma uchitha phansi indlela amaza emoyeni adala ngayo futhi asakazwa.
Kuyini ama-Waves Radio?
Cishe ujwayele i-AM, okumele i- Amplitude Modulation , ne-FM, okumele i- Frequency Modulation . Zombili izinhlelo zomsakazo we-AM ne-FM zithunyelwa emoyeni ngamagagasi omsakazo, okuyingxenye yohlobo olubanzi lwamagagasi kagesi ahlanganisa: ama-gamma rays, ama-ray, ama-ultraviolet, ukukhanya okubonakalayo, i-infrared, ne-microwave. Amagagasi e-electromagnetic aseduze nathi nxazonke ezindaweni ezahlukene. Amagagasi omsakazo abonisa izindawo ezifanayo nalokho okwenziwe amagagasi avela (isib. Ukucabangela, ukuklabalaza, ukuhlukanisa, ukukhipha), kodwa kube khona emvenini amehlo ethu angawaqondi.
Amagagasi e-electromagnetic akhiqizwa ngokushintsha okwamanje (AC), okuyinto amandla kagesi asetshenziselwa ukuqhuba kahle kakhulu zonke izinhlelo zokusebenza kanye / noma ubuchwepheshe emakhaya ethu nasezimpilweni - kusuka emashini okugeza kumathelevishini kumadivayisi ethu eselula . E-United States, i-alternating yamanje isebenza kuma-volts angu-120 ku-60 Hz. Lokhu kusho ukuthi ama-alternates wamanje (shintsha ukuqondisa) ecingweni izikhathi ezingu-60 ngomzuzwana. Amanye amazwe asebenzisa i-50 Hz njengezinga elijwayelekile. Nakuba kokubili ama-50 no-60 Hz abhekwa njengama-frequencies aphansi, ama-alternate currents ayenayo izinga eliyisisekelo lemisebe ye-electromagnetic (EMR). Lokhu kusho ukuthi amanye amandla kagesi aphunyuka ucingo futhi adluliselwa emoyeni. Ukuphakama kwemvamisa kagesi, amandla amaningi asebenzayo ekubalekela ucingo ukuya esikhaleni evulekile. Ngakho-ke, imisebe ye-electromagnetic ingachazwa ngokucacile ngokuthi 'ugesi emoyeni'.
I-Concept of Modulation
Ugesi emoyeni akulutho ngaphandle komsindo ongahleliwe. Ukuze iguqulwe ibe yizibonakaliso eziwusizo ezithumela ulwazi (umculo noma izwi) kufanele kuqala zilungiswe, futhi ukuguqulwa kwezimpawu kuyisisekelo sempawu zomsakazo we-AM ne-FM. Yilokho okushiwo yi-AM ne-FM, njengoba i-AM imele ukulinganisa kwe-amplitude kanye ne-FM imele ukuguquguquka kwezimpawu.
Elinye igama lokuguquguquka kwemvelo lishintsha. Imisebe ye-electromagnetic kumele ilandiswe noma ishintshwe ukuze kusetshenziswe njengomsakazo we-radio. Ngaphandle kokumodemu, akukho ulwazi oluzobe luqhutshwa yisignali yomsakazo. Ukuguqulwa kwemimoya kuyisimo esilula ukuqonda, ikakhulukazi njengoba sisizungezile. Umqondo wethu wombono uwuyisibonelo esihle sokuchaza indlela ukuguqulwa komzimba okusebenza ngayo. Ungaba nephepha elingenalutho esandleni sakho, kodwa akusizi ngalutho kuze kube yilapho lilungiswa noma liguquliwe ngendlela enenjongo. Omunye kuzodingeka abhale noma adwebe ephepheni ukuze akhulume ngolwazi oluwusizo.
Isizwa sethu sokuzwa esinye isibonelo esihle. Umoya ongenalutho kufanele ulungiselelwe noma ushintshwe ngomculo noma ngezwi noma umsindo ukuze ube usizo. Njengengxenye yephepha, ama-molecule akha umoya ayithwala ulwazi. Kodwa ngaphandle kolwazi lwangempela - amamaki ephepheni noma ozwakala emoyeni - awunawo lutho. Ngakho uma kuziwa emisakazweni yomsakazo, imisebe yombane (ugesi emoyeni) kumele ilandiswe ngolwazi olufunayo ukuthumela.
AM Broadcast Radio
Umsakazo we-AM usebenzisa ukuguquguquka kwe-amplitude futhi kuyindlela elula kakhulu yokusakazwa kwemsakazo. Ukuze uzwisise ukuguquguquka kwe-amplitude, cabanga ngesignali esingazinzile (noma i-wave) ukusakazwa ku-1000 kHz ku-AM band. I-amplitude (noma ukuphakama) kwesignali njalo ayiguquki noma ayi-modulated, ngakho-ke ayinayo imininingwane ewusizo. Lesi siginali esigxilile sikhiqiza umsindo kuphela kuze kube yilapho isetshenzisiwe ngolwazi, njengezwi noma umculo. Ukuhlanganiswa kokubili kuholela ekuguqulweni kwamandla okuphakama kwesiginali esizinzile, esanda futhi sinciphisa ngokulingana ngqo nolwazi. Ukushintsha kwe-amplitude kuphela, njengoba imvamisa ihlala ihlala isikhathi sonke.
Umsakazo we-AM emazweni aseMelika usebenza ngezikhathi ezahlukene kusuka ku-520 kHz kuya ku-1710 kHz. Amanye amazwe kanye nezifunda zinemibala ehlukahlukene yemvamisa. Umvuthwandaba othize uyaziwa ngokuthi imvamisa yenkampani yenethiwekhi , okuyinto imoto lapho isibonakaliso sangempela sithathwa kusuka ku-antenna ekusakazeni kumatanisi okwamukelayo.
Umsakazo we-AM unezinzuzo zokudlulisa umehluko omkhulu, ube neziteshi eziningi emkhakheni wezintambo ezinikeziwe, futhi utholakala kalula ngabamukeli. Kodwa-ke, izimpawu ze-AM zithinta umsindo futhi ziphazamisekile , njengesikhathi sokuduma kwezulu. Ugesi olwenziwe ngombani luveza ama-spikes omsindo athathwa yi-AM tuners. Umsakazo we-AM unomkhawulo womsindo olinganiselwe kakhulu, kusuka ku-200 Hz kuya ku-5 kHz, okwenza kube lula ukusebenziseka kumsakazo wokukhuluma futhi ungabi nomculo omncane. Futhi uma kuziwa kumculo, izimpawu ze-AM zingezansi yekhwalithi yomsindo kune-FM.
Ukusakazwa kwe-FM yomsakazo
Umsakazo we-FM usebenzisa ukuguqulwa kwezimvamisa. Ukuze uzwisise ukuguquguquka kwemvamisa, cabanga isignali ngevolumu ehlala njalo nobukhulu. Ukuvama kwesignali kungashintshi noma kungalungisiwe, ngakho akukho lwazi oluwusizo oluqukethwe. Kodwa uma ulwazi lunikezwe kule signal, inhlanganisela ibangela ushintsho kumvamisa , okuhambisana ngqo nolwazi. Uma imvamisa ihlelwe phakathi kokuphansi nokuphezulu, umculo noma izwi liyadluliselwa ngemvamisa yenethiwekhi. Kodwa kuphela izinguquko zenyuka njengomphumela; i-amplitude isala njalo isikhathi sonke.
Umsakazo we-FM usebenza kuma-87.5 MHz kuya ku-108.0 MHz, okuyi-range ephakeme kakhulu yama frequency kune-AM umsakazo. Ububanzi bebanga lokudluliselwa kwe-FM lincane kakhulu kune-AM - ngokuvamile ngaphansi kwamamayela angu-100. Noma kunjalo, umsakazo we-FM ungcono kakhulu kumculo; ububanzi bomkhawulokudonsa ophakeme we-30 Hz kuya ku-15 kHz uveza ikhwalithi yomsindo esivame ukuyilalela nokuyijabulela. Kodwa ukuze ube nendawo enkulu yokufaka, ukuthunyelwa kwe-FM kudinga iziteshi ezengeziwe ukuba zithwale izimpawu eziqhubekayo.
Ukusakazwa kwe-FM nakho kuvame ukuqhutshwa ku-stereo - iziteshi ezimbalwa ze-AM nazo zikwazi ukusakaza izimpawu ze-stereo. Futhi nakuba izimpawu ze-FM zingekho ngaphansi komsindo nokuphazanyiswa, zinganciphisa izithiyo ezingokwenyama (isb. Izakhiwo, amagquma, njll), ezithinta ukwamukela jikelele. Yingakho ungathatha iziteshi zomsakazo kalula kwezinye izindawo kunabanye, kungakhathaliseki ukuthi kungaphakathi kwekhaya lakho noma eduze kwedolobha.