Ukubheka Amafomu Ahlukene Okusakazwa Kwemsakazo
Ukusakazwa kwemisakazo ukuhanjiswa kwe-wireless unidirectional phezu kwamagagasi omsakazo okuhloswe ukufinyelelela izilaleli eziningi. Ukusakazwa kuhlanganisa ubuchwepheshe obuningi obudlulisela okuqukethwe noma idatha. Ngenxa yokwethulwa kobuchwepheshe obusha, indlela umsakazo ichazwa ngayo iyashintsha ngisho nangaphezulu.
I-Nielsen Audio, eyayibizwa ngokuthi i-Arbitron, inkampani e-United States esekelwe emazweni asakaza umsakazo, ichaza "isiteshi somsakazo" njengesiteshi se-AM noma FM esinikezwe ilayisense; isiteshi se-HD Radio; ukusakaza kwe-intanethi kwesiteshi esinelayisensi sikahulumeni esivele sikhona; enye yeziteshi zomsakazo wesathelayithi kusuka ku-XM Satellite Radio noma i-Sirius Satellite Radio; noma, mhlawumbe, isiteshi esingekho ilayisensi kahulumeni.
Ukusakazwa komsakazo wendabuko
Ukusakazwa komsakazo wendabuko kuhlanganisa iziteshi ze-AM ne-FM. Kunezinhlobo eziningana ze-subtypes, okuwukuthi ukusakazwa kwezebhizinisi, okungezona ezokuhweba ezemfundo, izinhlobo zokusakaza zomphakathi kanye nezinzuzo ezingenzi nzuzo kanye nomsakazo womphakathi kanye neziteshi zomsakazo wezemfundo ekolishi emhlabeni wonke.
Indlela yokuqala yokuqala yomsakazo womsakazo, obizwa ngokuthi i-valve thermionic, yasungulwa ngo-1904 ngu-physicist we-English John Ambrose Fleming. Ukusakaza kokuqala kubikwa ukuthi kwenzeke ngo-1909 nguCharles Herrold eCalifornia. Isiteshi sakhe kamuva saba yi-KCBS, okwamanje ikhona njengamanje esiteshini sama-AM esivela eSan Francisco.
AM Radio
I-AM, uhlobo lokuqala lomsakazo, luyaziwa nangokuthi i-amplitude modulation. Ichazwa ngokuthi ubukhulu begagasi lenkampani yenethiwekhi elihlukahlukene ngokuhambisana nesici esithile sesignali yokumisa. Ibhendi le-medium-wave lisetshenziselwa emhlabeni jikelele nge-AM ekusakazeni.
AM ukusakaza kwenzeka eNyakatho Melika yaseMelika emkhawulweni wezinombolo we-525 kuya ku-1705 kHz, owaziwa nangokuthi "i-band evamile yokusakaza." Le bhanti yanda eminyakeni yama-1990 ngokungeza iziteshi eziyisishiyagalolunye kusukela ngo-1605 kuya ku-1705 kHz. isignali ukuthi ingatholakala futhi iphenduke umsindo ngezinto ezilula.
Ukungahambi kahle komsakazo we-AM isignali ingaphansi kokuphazamiseka kombani, iziphepho zikagesi nezinye ukuphazanyiswa kwe-electromagnetic njengemisebe yelanga. Amandla amashaneli wesifunda abelana ngemvamisa kufanele ancishiswe ebusuku noma abekwe obala ukuze agweme ukuphazanyiswa. Ebusuku, izimpawu ze-AM zingaya ezindaweni eziningi ezikude, noma kunjalo, ngaleso sikhathi ukukhula kwesignali kungaba nzima kakhulu.
Umsakazo we-FM
I-FM, eyaziwa nangokuthi i-modulation modulation, yasungulwa ngu-Edwin Howard Armstrong ngo-1933 ukuze anqobe inkinga yokuphazanyiswa kwe-radio-frequency, okuyinto eyenza umsakazo we-AM. Ukufometha kwefayili kwakungendlela yokugcizelela idatha engxenyeni ehamba phambili ngokushintshashintsha imvamisa yesikhala. I-FM ivela kuma-airwaves e-VHF ku-range 88 kuya ku-108 MHz.
Isevisi yomsakazo we-FM yangempela e-US yayiyi-Yankee Network, e-New England. Ukusakazwa kwe-FM njalo kwaqala ngo-1939 kodwa akuzange kube yingozi enkulu embonini yezokusakaza ye-AM. Kwakudingeka ukuthengwa komamukeli okhethekile.
Njengengxenye yokuhweba, yahlala isisindo esincane esasetshenziselwa imisindo yomculo kuze kube ngawo-1960. Iziteshi ezihamba phambili ze-AM zithole amalayisensi e-FM futhi zivame ukusakaza izinhlelo ezifanayo esiteshini se-FM njengasesiteshini samamanje, esibizwa nangokuthi simulcasting.
I-Federal Communications Commission inciphisa lo mkhuba ngawo-1960. Ngama-1980, kusukela cishe wonke ama-radios amasha afaka phakathi kokubili AM and FM, i-FM yaba isikhulu esiphezulu, ikakhulukazi emadolobheni.
I-Newer Technology Technology
Kube nezinhlobo eziningana zeziteshi zomsakazo ezisebenzisa ubuchwepheshe obusakazo obusakazwa kusukela ngo-2000, umsakazo wesathelayithi, umsakazo we-HD nomsakazo we-intanethi.
I-Satellite Satellite
I-SIRIUS XM Satellite Radio, ukuhlanganiswa kwezinkampani zomculo zomsakazo wokuqala wokuqala waseMelika, ihlinzeka izinhlelo ezizigidi zezilaleli ezikhokhela imishini yomsakazo ekhethekile kanye nemali yokubhalisa yanyanga zonke.
Ukusakazwa kokuqala kweMelika kwomsakazo wesathelayithi kwakuyi-XM ngoSeptemba 2001.
Ukuhlela kugoboliswa kusuka emhlabeni kuya kwisathelaythi, bese kubuyiselwa emhlabeni. Ama-antenna akhethekile athola ulwazi lwedijithali ngokuqondile kwi-satellites noma eziteshini zokuphinda ezigcwalisa izikhala.
I-HD Radio
Ubuchwepheshe bomsakazo we-HD udlulisa umsindo we-digital nedatha eceleni kwamasignali e-AM ne-FM anikeziwe. Kusukela ngoJuni 2008, iziteshi zomsakazo ezingaphezu kuka-1 700 HD zazisakaza iziteshi zomsakazo ze-2,432 HD.
Ngokusho kwe-Ibiquity, umthuthukisi wezobuchwepheshe, umsakazo we-HD wenza "... i-AM yakho izwakala sengathi umsindo we-FM ne-FM unjengama-CD."
I-Ibiquity Digital Corporation, i-consortium yaseMelika yezinkampani zangasese, ithi umsakazo we-HD unikeza ukuxhunyaniswa kwe-FM, okukwazi ukusakaza imifudlana eminingi yezinhlelo ngaphezu komvuthwandaba we-FM owodwa ongenayo i-static, free reception.
Umsakazo we-Inthanethi
Umsakazo we-intanethi, owaziwa ngokuthi ukusakazwa okwenziwe noma umsakazo womsakazo, uzizwa njengomsakazo futhi uzwakala njengomsakazo kodwa awusona umsakazo ngempela. Umsakazo we-Intanethi unikeza inkohliso yomsakazo ngokuhlukanisa umsindo emaphaketheni amancane kolwazi lwedijithali, bese uyithumela kwenye indawo, njengekhompiyutha noma i-smartphone, bese uphinde uhlanganise amaphakethe abe ngumsakazo owodwa oqhubekayo womsindo.
Ama-podcasts ayisibonelo esihle sendlela umsakazo we-inthanethi osebenza ngayo. Ama-podcasts, i-portmanteau noma inhlanganisela yamazwi we-iPod nokusakaza, iyinkambo ye-episodic yamafayela womidijithali we-digital umsebenzisi angasetha ukuze iziqephu ezintsha zilandwe ngokuzenzakalelayo nge-syndication webhubhu kumakhompiyutha wendawo yomsebenzisi noma isidlali semidiya yedijithali.