同軸電纜和大對數電纜的區別
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來源：未知發布日期：2020-03-17 10:22
同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)先由兩根同(tong)(tong)(tong)軸(zhou)(zhou)心(xin)、相互絕緣的圓柱(zhu)形(xing)金屬導(dao)體構成(cheng)基(ji)本單(dan)元(同(tong)(tong)(tong)軸(zhou)(zhou)對)，再由單(dan)個或多(duo)個同(tong)(tong)(tong)軸(zhou)(zhou)對組成(cheng)的電(dian)(dian)(dian)(dian)纜(lan)(lan)。同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)從用(yong)途上分(fen)(fen)可(ke)分(fen)(fen)為基(ji)帶同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)和寬(kuan)帶同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)(即網絡同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)和視頻同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan))。同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)分(fen)(fen)50Ω 基(ji)帶電(dian)(dian)(dian)(dian)纜(lan)(lan)和75Ω寬(kuan)帶電(dian)(dian)(dian)(dian)纜(lan)(lan)兩類。基(ji)帶電(dian)(dian)(dian)(dian)纜(lan)(lan)又分(fen)(fen)細同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)和粗同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)。基(ji)帶電(dian)(dian)(dian)(dian)纜(lan)(lan)僅僅用(yong)于數字(zi)傳輸(shu)，數據率可(ke)達10Mbps。同(tong)(tong)(tong)軸(zhou)(zhou)電(dian)(dian)(dian)(dian)纜(lan)(lan)由里(li)到外分(fen)(fen)為四(si)層(ceng)(ceng)：中心(xin)銅線(xian)(xian)，塑料絕緣體，網狀導(dao)電(dian)(dian)(dian)(dian)層(ceng)(ceng)和電(dian)(dian)(dian)(dian)線(xian)(xian)外皮。電(dian)(dian)(dian)(dian)流傳導(dao)與(yu)中心(xin)銅線(xian)(xian)和網狀導(dao)電(dian)(dian)(dian)(dian)層(ceng)(ceng)行(xing)程(cheng)的回路。因為中心(xin)銅線(xian)(xian)和網狀導(dao)電(dian)(dian)(dian)(dian)層(ceng)(ceng)為同(tong)(tong)(tong)軸(zhou)(zhou)關系而得(de)名。
同軸電(dian)(dian)纜(lan)的(de)(de)得名與它的(de)(de)結(jie)構相關(guan)。同軸電(dian)(dian)纜(lan)也是局域網中最常見的(de)(de)傳輸介(jie)質之一。它用(yong)來(lai)傳遞信息的(de)(de)一對導(dao)(dao)體是按照一層(ceng)圓筒(tong)式的(de)(de)外(wai)(wai)導(dao)(dao)體套在(zai)內導(dao)(dao)體(一根細芯(xin))外(wai)(wai)面(mian)，兩個導(dao)(dao)體間用(yong)絕(jue)緣(yuan)材料互相隔離的(de)(de)結(jie)構制選的(de)(de)，外(wai)(wai)層(ceng)導(dao)(dao)體和中心(xin)軸芯(xin)線的(de)(de)圓心(xin)在(zai)同一個軸心(xin)上(shang)，所以(yi)叫做(zuo)同軸電(dian)(dian)纜(lan)，同軸電(dian)(dian)纜(lan)之所以(yi)設計成這樣，也是為了防止外(wai)(wai)部電(dian)(dian)磁波(bo)干擾異常信號的(de)(de)傳遞。
同軸電纜，比如寬帶、多路電話和電視。
大對數(shu)即多(duo)對數(shu)的(de)意(yi)思，系指很多(duo)一(yi)(yi)對一(yi)(yi)對的(de)電纜(lan)(lan)(lan)組成(cheng)一(yi)(yi)小捆(kun)，再由(you)很多(duo)小捆(kun)組成(cheng)一(yi)(yi)大捆(kun)(更大對數(shu)的(de)電纜(lan)(lan)(lan)則再由(you)一(yi)(yi)大捆(kun)一(yi)(yi)大捆(kun)組成(cheng)一(yi)(yi)根大電纜(lan)(lan)(lan))。由(you)于線特別多(duo)，且顏色固定(ding)在某幾種色，因此沒有掌握(wo)技巧是不容易(yi)區分(fen)出所有線纜(lan)(lan)(lan)對應(ying)的(de)線序的(de)。下面介紹一(yi)(yi)下如何區分(fen)線序：
基本色：a 白 紅 黑 黃 紫 b 藍 桔 綠(lv) 綜 灰
區分法：
1. 線(xian)對區(qu)分(fen)法
每(mei)對線由a和b色(se)組成(cheng)。如：a色(se)的白色(se)分別與(yu)b色(se)中各色(se)組成(cheng)1-5號線對。依此類(lei)推(tui)可組成(cheng)25對，這25對為一基本單位。
2. 扎(zha)帶區(qu)分法
基(ji)本(ben)單位間用(yong)不同顏(yan)色(se)(se)的扎帶扎起來(lai)以區(qu)分順序(xu)。扎帶顏(yan)色(se)(se)也由(you)基(ji)本(ben)色(se)(se)組(zu)成，順序(xu)與線(xian)對排(pai)列順序(xu)相同。若(ruo)：白藍扎帶為第(di)一組(zu)，線(xian)序(xu)號(hao)1-25;白桔扎帶為第(di)二組(zu)線(xian)序(xu)號(hao)26-50，依此類(lei)推。
大(da)對(dui)數線即(ji)大(da)對(dui)數電(dian)(dian)纜(lan)，比如(ru)電(dian)(dian)話電(dian)(dian)纜(lan)。
