(一)概述大家知道,彩电的“黑屏”故障绝大多数发生在飞利蒲机心当中,这是由于飞利浦机心中特有的“沙堡”脉冲的特殊作用所决定的。“黑屏”故障常见的表现形式为:有伴音、无光栅、无字符或有伴音、无光栅、有字符。但需要澄清的是,“黑屏”故障虽然有时就是无光栅,但二者的故障机理却截然有别。实践证明,“黑屏”故障是一种非行扫描电路故障所引起的无光栅现象。即在行扫描电路正常时,其他电路发生故障所引起的解码电路中基色或色差激励电路自动关闭,使视放管截止以后,造成的荧光屏无光。无光栅故障严格地说 (A) Overview As we all know, TV “black screen” failure occurred in the vast majority of Philips hearts, which is due to the unique “sand castle” pulse in the Philips movement determined by the special role. Common manifestations of “black screen” failures are: no sound, no raster, no character or sound, no raster, with characters. However, it needs to be clarified that although the “black screen” fault sometimes has no grating, the fault mechanism of the two is entirely different. Practice has proved that “black screen” failure is a non-line scan circuit failure caused by the phenomenon of no grating. That is, the line scan circuit is normal, the other circuit failure caused by the decoding circuit in the primary color or color difference excitation circuit automatically shut down, so that after the release of the tube, the resulting screen dull. No grating fault Strictly speaking