功放機常見故障怎么維修

一、整機不工作

1、故障現象

整(zheng)機不工作的故(gu)障表現為通(tong)電(dian)(dian)后放(fang)大器無任何(he)顯(xian)示，各功能鍵均(jun)失效，也無任何(he)聲音，像未通(tong)電(dian)(dian)時一樣。

2、檢修方法

檢修時首先(xian)應檢查電(dian)(dian)源(yuan)電(dian)(dian)路，接(jie)通電(dian)(dian)源(yuan)，用萬用表測(ce)量電(dian)(dian)源(yuan)插頭兩端的直流電(dian)(dian)阻(zu)值(zhi)，正常時幾百歐的電(dian)(dian)阻(zu)值(zhi)。如果差距太大(da)，且電(dian)(dian)源(yuan)變壓(ya)器嚴重發熱，說明電(dian)(dian)源(yuan)變壓(ya)器的初級回(hui)路有(you)(you)局部短路處(chu)。如果無窮大(da)，應檢查變壓(ya)器初級繞(rao)組是不是開路、保險絲有(you)(you)沒有(you)(you)熔斷、插頭和電(dian)(dian)源(yuan)線間(jian)有(you)(you)沒有(you)(you)斷線。

該圖片由注冊用戶"橘子de殿堂"提供，版權聲明反饋

二、無聲音輸出

1、故障現象

無聲(sheng)故障表現為操作各功能(neng)鍵時(shi)，有相應的狀態(tai)顯示，但無信(xin)號(hao)輸出。

2、檢修方法

檢(jian)(jian)修有(you)(you)保護電(dian)(dian)(dian)(dian)(dian)路的放大器時(shi)，應(ying)(ying)看開(kai)機后保護繼(ji)電(dian)(dian)(dian)(dian)(dian)器能(neng)不(bu)(bu)(bu)能(neng)吸合(he)。如(ru)果(guo)(guo)繼(ji)電(dian)(dian)(dian)(dian)(dian)器無動(dong)作，應(ying)(ying)測量功(gong)放電(dian)(dian)(dian)(dian)(dian)路中點(dian)功(gong)放，過(guo)流檢(jian)(jian)測電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)是(shi)不(bu)(bu)(bu)是(shi)正(zheng)常(chang)(chang)、輸出電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)有(you)(you)沒有(you)(you)偏移。若中點(dian)輸出電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)偏移或過(guo)流檢(jian)(jian)測電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)異常(chang)(chang)，說明功(gong)率放大電(dian)(dian)(dian)(dian)(dian)路有(you)(you)故障，應(ying)(ying)檢(jian)(jian)查正(zheng)、負(fu)電(dian)(dian)(dian)(dian)(dian)源(yuan)是(shi)否正(zheng)常(chang)(chang)。如(ru)果(guo)(guo)正(zheng)、負(fu)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)不(bu)(bu)(bu)對(dui)稱，可斷開(kai)正(zheng)、負(fu)電(dian)(dian)(dian)(dian)(dian)源(yuan)的負(fu)載電(dian)(dian)(dian)(dian)(dian)路，這樣判(pan)斷是(shi)功(gong)放電(dian)(dian)(dian)(dian)(dian)路有(you)(you)故障還是(shi)電(dian)(dian)(dian)(dian)(dian)源(yuan)電(dian)(dian)(dian)(dian)(dian)路本身不(bu)(bu)(bu)正(zheng)常(chang)(chang)。如(ru)果(guo)(guo)正(zheng)、負(fu)電(dian)(dian)(dian)(dian)(dian)源(yuan)正(zheng)常(chang)(chang)，應(ying)(ying)檢(jian)(jian)查功(gong)放電(dian)(dian)(dian)(dian)(dian)路中各(ge)放大管是(shi)不(bu)(bu)(bu)是(shi)損壞。

三、音輕

1、故障現象

音(yin)輕是(shi)指音(yin)頻信號在(zai)放大傳輸過程中(zhong)，因某個放大級放大量變化或在(zai)某個環節被(bei)衰減，使放大器的增(zeng)益(yi)下降或輸出功率變小。

2、檢修方法

檢修時，首先應檢查(cha)(cha)信(xin)號源和(he)音(yin)箱是否正常(chang)，可用(yong)替換(huan)的(de)辦法來(lai)檢查(cha)(cha)。然后(hou)(hou)檢查(cha)(cha)各類(lei)轉換(huan)開(kai)關和(he)控(kong)制電(dian)(dian)(dian)(dian)位器，看(kan)音(yin)量能否變大。如果(guo)都正常(chang)，那就看(kan)故(gu)障(zhang)是在(zai)前級(ji)(ji)還是后(hou)(hou)級(ji)(ji)電(dian)(dian)(dian)(dian)路(lu)(lu)。對于(yu)某一個聲道音(yin)輕，可將其前級(ji)(ji)電(dian)(dian)(dian)(dian)路(lu)(lu)輸(shu)(shu)出的(de)信(xin)號交換(huan)，輸(shu)(shu)入(ru)到(dao)另一聲道的(de)后(hou)(hou)級(ji)(ji)電(dian)(dian)(dian)(dian)路(lu)(lu)。如果(guo)音(yin)箱的(de)聲音(yin)大小不變，則故(gu)障(zhang)在(zai)后(hou)(hou)級(ji)(ji)電(dian)(dian)(dian)(dian)路(lu)(lu)。

四、噪聲大

1、故障現象

放大(da)器(qi)的噪(zao)聲有交(jiao)流聲、爆裂聲、感應噪(zao)聲和白噪(zao)聲等

2、檢修方法

檢修時(shi)，應(ying)先判斷噪聲來(lai)自于前級(ji)還是來(lai)自于后級(ji)電(dian)路。可(ke)把前、后級(ji)的信號連接插頭取下，若(ruo)噪聲明顯變小，說明故(gu)障在(zai)前級(ji)電(dian)路。反之，故(gu)障在(zai)后級(ji)電(dian)路。

如何保養功放機

1、用戶(hu)應(ying)將(jiang)功放(fang)機放(fang)置在(zai)(zai)干燥、通(tong)風的地方(fang)，避免(mian)在(zai)(zai)潮濕、高溫、油煙化學制劑有腐(fu)蝕(shi)性的環境中工(gong)作。

2、應將功放放置在安全、平穩(wen)、不易掉落(luo)的(de)臺面(mian)或(huo)(huo)機柜(ju)中使用，以免(mian)碰損或(huo)(huo)跌落(luo)在地上，將機器損壞或(huo)(huo)引起更(geng)大的(de)人為災害，如火災、觸電等。

3、應將功(gong)放避開(kai)電磁(ci)干擾嚴重的(de)環境，如日光燈鎮流器(qi)老化(hua)等放射(she)的(de)電磁(ci)干擾將會引起機(ji)器(qi)CPU程序錯(cuo)亂(luan)，導致機(ji)器(qi)不(bu)能正常工作。

4、功(gong)放機用完后(hou)，各功(gong)能(neng)鍵要復(fu)位。如(ru)果功(gong)能(neng)鍵長(chang)期不(bu)復(fu)位，其牽拉鈕簧長(chang)時期處于受(shou)力狀態，就容易(yi)造成功(gong)能(neng)失(shi)常。

5、開關音響電源(yuan)之(zhi)前，應把功(gong)(gong)放的(de)(de)音量電位(wei)器旋至最(zui)小，這是對功(gong)(gong)放和音箱的(de)(de)一項最(zui)有(you)效的(de)(de)保護手段。這時候功(gong)(gong)放的(de)(de)功(gong)(gong)率放大幾乎為零，至少在誤操作(zuo)時也(ye)不至于對音箱造成危害。

6、在長期不(bu)使用的情況下尤其(qi)在潮(chao)濕、高溫(wen)季節(jie)，最(zui)好(hao)每天通電半小時。這樣可利用機內元器件工作時產生的熱量來驅除(chu)潮(chao)氣，避免內部線圈(quan)(quan)、揚聲器音圈(quan)(quan)、變壓器等受(shou)潮(chao)霉斷。

7、每隔(ge)一(yi)段時間要用(yong)干凈潮(chao)濕(shi)的(de)軟(ruan)棉布擦拭機器表(biao)面。不用(yong)時，應用(yong)防(fang)塵罩或蓋布把機器蓋上(shang)，防(fang)止灰塵入(ru)內。

8、音響器材正(zheng)常的(de)工作(zuo)溫度應該為18℃～45℃。溫度太低(di)會降低(di)某些機器的(de)靈敏度，太高(gao)則容易燒壞元(yuan)(yuan)器件，或使(shi)元(yuan)(yuan)器件提(ti)早老(lao)化，夏天要特別注意降溫和(he)保(bao)持(chi)空氣流通。