论文部分内容阅读
一台飞跃12D1电视机,在收到电视节目时,无规则地产生声影全无的故障,且故障持续时间很短,只有数秒钟,故障过后又一次恢复正常,有时候一分钟内出现儿次故障,有时候连续几小时都正常。在无电视信号输入时也产生此毛病,即图象噪声和伴音噪声同时消失。由于故障持续时间很短,所以检修也比较困难。检修时用几只万用表同时监测高频头、中放、预视放、AGC电路的几个关键电压值,发现一旦故障出现时中放AGC和高放AGC电压都升到5V以上。进一步检查时发现,在故障
A leap 12D1 TV, when receiving the TV show, no sound and shadow generated a random failure, and the fault duration is very short, only a few seconds, once again after the fault back to normal, and sometimes appear within a minute Secondary failure, sometimes normal for hours. This problem also occurs when no television signal is input, that is, image noise and accompanying noise disappear at the same time. Due to the short duration of the fault, overhauling is also more difficult. Overhaul with several multimeter simultaneous monitoring of the tuner, in the release, pre-release, AGC circuit of several key voltage values found in the event of failure in the release AGC and AGC high voltage AGC above 5V. Further inspection found that the fault