论文部分内容阅读
一台熊猫3608型彩电,最初出现光栅亮暗闪烁的故障,持续数分钟后可恢复正常。经修理不但故障依然,而且发生冒烟新故障。断开电源打开后盖,发现主电源的FB706和D708已烧毁,保险电阻R708也已烧断。用万用表测得IX0689内电源调整管和保险管正常,于是用5.6Ω电阻暂行代替R708,并接上60W灯泡作假负载。通电开机发现灯泡耀眼,R708迅速“冒烟”,关机。测电源厚膜块第①、②、③脚(误差取样端)外围元件均正常,怀疑其内部损坏。但拆下测量其各引脚间直流阻值均正常。突然想起在拆取厚膜块时,烙铁头与焊点之间发出几声“吱吱”响声,怀
A panda 3608 color TV, the first grating light and dark flashing failure, after a few minutes to return to normal. Not only the failure of the repair, but also the emergence of new smoke. Disconnect the power to open the back cover and found the main power supply FB706 and D708 have been burned, insurance resistor R708 has also been blown. Use a multimeter to measure IX0689 internal power supply regulation tube and fuse normal, then temporarily replace the R708 with a 5.6Ω resistor, and connected to the 60W bulb for fake load. Turn on the power to find the lamp dazzling, R708 quickly “smoke”, shutdown. Measuring power thick film block ①, ②, ③ feet (error sampling end) peripheral components are normal, suspected of its internal damage. However, remove the measurement of the DC resistance between the pins are normal. Suddenly remembered in the demolition of thick film block, the tip between the soldering iron and issued a few “creak” sound, pregnant