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一、故障原因分析彩电彩色图像良好,但是图像蒙上一层网纹状干扰,大大影响收看效果。引起网纹状干扰有二个即:机外干扰和机内干扰。机外电磁干扰,如:电视机本振频率泄漏引起干扰,广播电台的干扰,高频加热设备干扰;在有线电视覆盖范围内.如果有线电视用户放大器被雷击或高温状态损坏.输出了网状信号等。机内网纹干扰的原因是:高放、中放、视放产生自激和高放 AGC 起控太迟。机内故障率最高的元件有:SAWF 声表面滤波器不良、38.0 MHz 图像检波中周与AFT 中周内部的电容发黑变质、画中画彩电的信号分
First, the failure analysis Color TV color image is good, but the image cast a layer of reticular interference, greatly affect the viewing effect. Mesh-shaped interference caused by two, namely: external interference and internal interference. External electromagnetic interference, such as: TV local frequency interference caused by leakage, radio interference, high frequency heating equipment interference; in the cable coverage. If the cable user amplifier is damaged by lightning or high temperature state. Signal and so on. The reason for the internal network interference is: high-placed, put, depending on the release of self-excited and high-AGC control too late. The highest failure rate in the machine components: SAWF surface acoustic wave filter is poor, 38.0 MHz image detection week and AFT weeks internal capacitance blackening deterioration, picture-in-picture TV signal points