故障现象:每当推动调音台右声道主推拉电位器时,音箱总会发出“沙沙”声。分析与检修:根据故障现象分析,该故障可能是因调音台上右主控输出推拉电位器出现触点和炭膜磨损或因灰尘积累而接触不良所致。检修时,只要通过直接触摸和试听就可以确定出故障部位。这种故障比较多见,尤其是功率放大器上的音量电位器经长期使用也会有类似的故障出现。在一些高质量的调音台上,虽然其推拉电位器不采用炭膜结构的接触方式而采用光电结构,但是灰尘进去过多仍会出现故障,这种现象可以通过清洗来排除。对严重磨损的电位器应及时更换。荨 Symptom: Whenever you push the mixer right channel main push and pull potentiometer, the speaker will always issue “chars ” sound. Analysis and Maintenance: According to the analysis of the fault phenomenon, the fault may be caused by the mixer on the right master output push-pull potentiometer contacts and carbon film wear or due to dust accumulation and poor contact. Maintenance, as long as the direct touch and audition can determine the fault site. This kind of breakdown is more common, especially the volume potentiometer on the power amplifier will have a similar failure after long-term use. In some high-quality mixer, although the push-pull potentiometer does not use the carbon film structure of the contact mode and the use of optoelectronic structure, but too much dust will still fail, this phenomenon can be ruled out by cleaning. The serious wear and tear of the potentiometer should be promptly replaced. Nettle