故障现象：在使用过程中，激光仪面板处电压表显示为70V左右，琴键开关置“连续”状态下，踏下脚踏开关，机内5A玻管保险丝立即熔断，连续数次均如此。根据故障现象分析可能是机内某一元器件短路造成保险丝熔断。卸下后面板，即可看到仪器内部的结构情况。首先从外观上察看元器 Symptoms: During use, the voltmeter at the panel of the laser instrument is displayed as about 70V. When the key switch is set to “continuous” state, the foot switch is stepped on and the 5A glass tube fuse in the machine is blown immediately. This is the case for several consecutive times. According to the analysis of the fault phenomenon, the fuse may be blown due to a short circuit in one component in the machine. Remove the back panel to see the internal structure of the instrument. First look at the appearance of the device