眾所周知(zhi)，日常(chang)生活中我(wo)們使用功(gong)放機，時間久了之后可能(neng)就會(hui)出(chu)現各種各樣的問題，那么(me)(me)，功(gong)放機出(chu)現問題的情況下應該怎么(me)(me)解決(jue)(jue)呢？隔山(shan)如(ru)隔行，雖然不(bu)是所有的人都能(neng)解決(jue)(jue)的，但(dan)是了解一些相關方(fang)面的知(zhi)識會(hui)使你迎刃而解。下面介紹功(gong)放機的三種常(chang)見故障及維修方(fang)法。

一、整機不工作(zuo)

整(zheng)機不工作(zuo)的(de)故(gu)障(zhang)表現為通(tong)電(dian)后放大器無(wu)任何(he)顯示，各功能鍵均失效，也無(wu)任何(he)聲音，像(xiang)未通(tong)電(dian)時一(yi)樣。

檢修(xiu)時首先應(ying)檢查電(dian)(dian)源(yuan)(yuan)(yuan)電(dian)(dian)路(lu)。可(ke)用萬用表測量電(dian)(dian)源(yuan)(yuan)(yuan)插頭(tou)兩端的直流電(dian)(dian)阻值(zhi)(電(dian)(dian)源(yuan)(yuan)(yuan)開關(guan)應(ying)接(jie)通(tong)(tong))，正常(chang)時應(ying)有數百歐姆的電(dian)(dian)阻值(zhi)。若測得(de)阻值(zhi)偏小許多，且(qie)電(dian)(dian)源(yuan)(yuan)(yuan)變(bian)壓器(qi)(qi)嚴重發熱，說明電(dian)(dian)源(yuan)(yuan)(yuan)變(bian)壓器(qi)(qi)的初級(ji)(ji)(ji)回(hui)路(lu)有局部短路(lu)處；若測得(de)阻值(zhi)為大，應(ying)檢查保險(xian)絲是否熔斷、變(bian)壓器(qi)(qi)初級(ji)(ji)(ji)繞(rao)組是否開路(lu)、電(dian)(dian)源(yuan)(yuan)(yuan)線(xian)與插頭(tou)之間有無斷線(xian)。有的機器(qi)(qi)增加了溫(wen)度保護裝置，在電(dian)(dian)源(yuan)(yuan)(yuan)變(bian)壓器(qi)(qi)的初級(ji)(ji)(ji)回(hui)路(lu)中接(jie)人了電(dian)(dian)流保險(xian)絲(通(tong)(tong)常(chang)安裝在電(dian)(dian)源(yuan)(yuan)(yuan)變(bian)壓器(qi)(qi)內部，將變(bian)壓器(qi)(qi)外部的絕緣紙去掉即(ji)可(ke)見到)，它損壞后也會使電(dian)(dian)源(yuan)(yuan)(yuan)變(bian)壓器(qi)(qi)初級(ji)(ji)(ji)回(hui)路(lu)開路(lu)。

中文字幕日韓歐美一區二區三區:重慶音響工程公司稱若電源插頭兩端阻值正常，可通電測量電源電路各輸出電壓是否正常。對于采用系統控制微處理器或邏輯控制電路的放大器，應著重檢查該控制電路的供電電壓(通常為+5V)是否正常。如無+5V電壓，應測量三端穩壓集成電路7805的輸入端電壓是否正常，若輸入端電壓不正常，應檢查整流、濾波電路。若7805輸入端電壓正常，而輸出端無十5V電壓或電壓偏低，可斷開負載看+5V電壓能否恢復正常。若+5V電壓正常，則故障在負載電路；若+5V電壓仍不正常，則故障在7805本身。若系統控制電路的+5V供電電壓正常，應再檢查微處理器的時鐘及復位信號是否正常、鍵控與顯示驅動電路有無損壞。

二、噪聲(sheng)大

放(fang)大器的(de)噪(zao)聲(sheng)有交流(liu)聲(sheng)、爆裂(lie)聲(sheng)、感應噪(zao)聲(sheng)和白噪(zao)聲(sheng)等。

檢修時，應先(xian)判斷噪(zao)(zao)聲(sheng)(sheng)來自(zi)于(yu)前(qian)(qian)級(ji)(ji)還是(shi)(shi)來自(zi)于(yu)后(hou)級(ji)(ji)電(dian)(dian)(dian)(dian)路。可把前(qian)(qian)、后(hou)級(ji)(ji)的(de)信(xin)號連接插頭取下，若(ruo)噪(zao)(zao)聲(sheng)(sheng)明顯變小，說明故障(zhang)在前(qian)(qian)級(ji)(ji)電(dian)(dian)(dian)(dian)路；反之(zhi)，故障(zhang)在后(hou)級(ji)(ji)電(dian)(dian)(dian)(dian)路。交(jiao)流(liu)聲(sheng)(sheng)是(shi)(shi)指聽感低沉、單調(diao)而穩(wen)定的(de)100Hz交(jiao)流(liu)哼聲(sheng)(sheng)，主要是(shi)(shi)電(dian)(dian)(dian)(dian)源(yuan)部分濾波不良所致，應著重(zhong)檢查電(dian)(dian)(dian)(dian)源(yuan)整流(liu)、濾波和(he)穩(wen)壓(ya)元件有無(wu)損壞。前(qian)(qian)、后(hou)級(ji)(ji)放(fang)大電(dian)(dian)(dian)(dian)路電(dian)(dian)(dian)(dian)源(yuan)端(duan)的(de)退(tui)耦電(dian)(dian)(dian)(dian)容(rong)虛焊或失(shi)效(xiao)，也會產生一種類(lei)似交(jiao)流(liu)聲(sheng)(sheng)的(de)低頻振蕩噪(zao)(zao)聲(sheng)(sheng)。

感應噪(zao)聲(sheng)(sheng)是(shi)(shi)成(cheng)分(fen)(fen)較復雜(za)且刺耳的(de)(de)交流(liu)(liu)聲(sheng)(sheng)，主要是(shi)(shi)前(qian)(qian)級(ji)電(dian)(dian)(dian)(dian)路(lu)中的(de)(de)轉(zhuan)換(huan)開關(guan)、電(dian)(dian)(dian)(dian)位(wei)器(qi)(qi)接(jie)地不良(liang)(liang)或信號(hao)連(lian)線(xian)屏蔽不良(liang)(liang)所致。爆裂(lie)聲(sheng)(sheng)是(shi)(shi)指間斷的(de)(de)“劈啪”、“咔(ka)咔(ka)”聲(sheng)(sheng)，在(zai)前(qian)(qian)級(ji)電(dian)(dian)(dian)(dian)路(lu)中，應檢查(cha)信號(hao)輸(shu)入(ru)插頭與插座、轉(zhuan)換(huan)開關(guan)、電(dian)(dian)(dian)(dian)位(wei)器(qi)(qi)等(deng)是(shi)(shi)否接(jie)觸不良(liang)(liang)，耦合(he)電(dian)(dian)(dian)(dian)容有無虛焊、漏(lou)電(dian)(dian)(dian)(dian)等(deng)。后(hou)級(ji)放大電(dian)(dian)(dian)(dian)路(lu)應檢查(cha)繼電(dian)(dian)(dian)(dian)器(qi)(qi)觸點是(shi)(shi)否氧化、輸(shu) 入(ru)耦合(he)電(dian)(dian)(dian)(dian)容有無漏(lou)電(dian)(dian)(dian)(dian)或接(jie)觸不良(liang)(liang)。另(ling)外(wai)，后(hou)級(ji)電(dian)(dian)(dian)(dian)路(lu)中的(de)(de)差分(fen)(fen)輸(shu)入(ru)管(guan)或恒流(liu)(liu)管(guan)軟擊(ji)穿(chuan)，也會產生(sheng)類似電(dian)(dian)(dian)(dian)火花的(de)(de)“咔(ka)咔(ka)”噪(zao)聲(sheng)(sheng)。白噪(zao)聲(sheng)(sheng)是(shi)(shi)指無規則(ze)的(de)(de)連(lian)續“沙沙”聲(sheng)(sheng)，通常(chang)是(shi)(shi)由(you)前(qian)(qian)、后(hou)級(ji)放大電(dian)(dian)(dian)(dian)路(lu)中的(de)(de)輸(shu)入(ru)級(ji)晶體管(guan)、場效應管(guan)或運放集成(cheng)電(dian)(dian)(dian)(dian)路(lu)的(de)(de)性能不良(liang)(liang)產生(sheng)的(de)(de)本(ben)底噪(zao)聲(sheng)(sheng)，檢修時，可用同規格的(de)(de)元件代(dai)換(huan)試(shi)之。

三、音量輕

專業中文字幕日韓歐美一區二區三區:音響工程公司稱所謂音輕故障，是指音頻信號在放大傳輸過程中，因某個放大級放大量變化或在某個環節被衰減，使放大器的增益下降或輸出功率變小。檢修時，首先應檢查信號源和音箱是否正常，可用替換的辦法來檢查。然后檢查各類轉換開關和控制電位器，看音量能否變大。

若(ruo)以上各部分均正(zheng)常，應(ying)判(pan)斷出(chu)(chu)(chu)故(gu)障是(shi)在前(qian)級(ji)(ji)還(huan)是(shi)在后(hou)級(ji)(ji)電路(lu)(lu)。對于某一(yi)個聲(sheng)(sheng)(sheng)道音輕，可將(jiang)其前(qian)級(ji)(ji)電路(lu)(lu)輸(shu)(shu)出(chu)(chu)(chu)的(de)(de)信號(hao)交換輸(shu)(shu)入(ru)到另一(yi)聲(sheng)(sheng)(sheng)道的(de)(de)后(hou)級(ji)(ji)電路(lu)(lu)，若(ruo)音箱的(de)(de)聲(sheng)(sheng)(sheng)音大(da)小不(bu)變，則故(gu)障在后(hou)級(ji)(ji)電路(lu)(lu)；反之(zhi)，故(gu)障在前(qian)級(ji)(ji)電路(lu)(lu)。后(hou)級(ji)(ji)放(fang)大(da)電路(lu)(lu)造成的(de)(de)音輕，主要有輸(shu)(shu)出(chu)(chu)(chu)功(gong)率不(bu)足(zu)和增益(yi)不(bu)夠兩種原因。可用(yong)適當加大(da)輸(shu)(shu)入(ru)信號(hao)(例(li)如將(jiang)收錄機輸(shu)(shu)出(chu)(chu)(chu)給揚聲(sheng)(sheng)(sheng)器(qi)的(de)(de)信號(hao)直(zhi)接加至后(hou)級(ji)(ji)功(gong)放(fang)電路(lu)(lu)的(de)(de)輸(shu)(shu)入(ru)端，改變收錄機的(de)(de)音量，觀察功(gong)放(fang)輸(shu)(shu)出(chu)(chu)(chu)的(de)(de)變化)的(de)(de)方(fang)法來判(pan)斷是(shi)哪(na)種原因引起的(de)(de)。

若加(jia)大(da)(da)輸(shu)(shu)入信號(hao)后，輸(shu)(shu)出(chu)的(de)(de)聲音(yin)足(zu)夠大(da)(da)，說明功放輸(shu)(shu)出(chu)功率足(zu)夠，只(zhi)是(shi)增(zeng)益(yi)降(jiang)低，應著(zhu)重檢(jian)(jian)查(cha)繼(ji)電(dian)(dian)(dian)(dian)器(qi)觸點有無(wu)接觸電(dian)(dian)(dian)(dian)阻(zu)(zu)增(zeng)大(da)(da)、輸(shu)(shu)入耦合電(dian)(dian)(dian)(dian)容容量減小、隔離電(dian)(dian)(dian)(dian)阻(zu)(zu)阻(zu)(zu)值(zhi)(zhi)增(zeng)大(da)(da)、負(fu)(fu)反(fan)饋(kui)電(dian)(dian)(dian)(dian)容容量變小或(huo)(huo)開(kai)路(lu)、負(fu)(fu)反(fan)饋(kui)電(dian)(dian)(dian)(dian)阻(zu)(zu)阻(zu)(zu)值(zhi)(zhi)增(zeng)大(da)(da)或(huo)(huo)開(kai)路(lu)等(deng)現象。若加(jia)大(da)(da)輸(shu)(shu)入信號(hao)后，輸(shu)(shu)出(chu)的(de)(de)聲音(yin)出(chu)現失(shi)真(zhen)，音(yin)量并(bing)無(wu)顯著(zhu)增(zeng)大(da)(da)，說明后級放大(da)(da)器(qi)的(de)(de)輸(shu)(shu)出(chu)功率不足(zu)，應先(xian)檢(jian)(jian)查(cha)放大(da)(da)器(qi)的(de)(de)正、負(fu)(fu)供電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓是(shi)否偏(pian)低(若只(zhi)是(shi)一(yi)個聲道音(yin)輕(qing)，可(ke)不必檢(jian)(jian)查(cha)電(dian)(dian)(dian)(dian)源(yuan)供電(dian)(dian)(dian)(dian))、功率管(guan)或(huo)(huo)集成(cheng)電(dian)(dian)(dian)(dian)路(lu)的(de)(de)性(xing)能是(shi)否變差、發射極電(dian)(dian)(dian)(dian)阻(zu)(zu)阻(zu)(zu)值(zhi)(zhi)有無(wu)變大(da)(da)等(deng)。前級電(dian)(dian)(dian)(dian)路(lu)中轉換開(kai)關、電(dian)(dian)(dian)(dian)位器(qi)所造(zao)成(cheng)的(de)(de)音(yin)輕(qing)，采用直(zhi)觀檢(jian)(jian)查(cha)較(jiao)易發現，可(ke)對其進行清洗或(huo)(huo)更換。如懷(huai)疑某信號(hao)耦合電(dian)(dian)(dian)(dian)容失(shi)效，可(ke)用同值(zhi)(zhi)電(dian)(dian)(dian)(dian)容并(bing)聯試(shi)之；放大(da)(da)管(guan)或(huo)(huo)運(yun)放集成(cheng)電(dian)(dian)(dian)(dian)路(lu)性(xing)能不良，也可(ke)用代換法檢(jian)(jian)查(cha)。另外，負(fu)(fu)反(fan)饋(kui)元件有問題(ti)，也會造(zao)成(cheng)電(dian)(dian)(dian)(dian)路(lu)增(zeng)益(yi)下降(jiang)。