故障现象:开机后光栅极亮,且有满屏白回扫线,伴音正常。分析与检修:图1为该机末级视放电路原理图。开机后测得显像管各极电压除阴极③、⑦、⑨脚电压为0.4V左右外,其他各脚电压均正常。顺着③、⑦、⑨脚线路查到视放集成块TDA6103Q的⑦、⑧、⑨脚,测得该三个脚电压也为0.4V左右,顺便测得TDA6103Q①、②、③脚电压均为0.6V,④脚接地,⑤脚电压为0.1V,⑥脚为200V,关机,把视放板从显像管上拔 Symptom: After turning on the grating very bright, and full screen white rewind line, sound normal. Analysis and Overhaul: Figure 1 shows the final stage of the machine put the circuit schematic. After the boot measured the cathode voltage in addition to cathode cathode ③, ⑦, ⑨ pin voltage is about 0.4V, the other pin voltage are normal. Along the ③, ⑦, ⑨ foot line found to see the integration of blocks TDA6103Q ⑦, ⑧, ⑨ feet measured the voltage of the three feet is about 0.4V, by the way measured TDA6103Q ①, ②, ③ foot voltage is 0.6 V, ④ feet grounded, ⑤ pin voltage is 0.1V, ⑥ pin is 200V, shutdown, put the video board from the picture tube up