Fault phenomenon: Characters are displayed when the device is turned on, but no channels can be received. For Skyworth TV, characters are displayed upon startup, but no channels can be received. Analysis and repair: Upon turning on the device, measure the voltage of each pin of TU101 and find that the AGC voltage is abnormal. Measure IC300?45 foot (TU-AGC) to be 0V, so suspect that IC300 is damaged. Contact Beijing Skyworth TV after-sales service hotline. After replacement, the fault persists, then suspect it's a data issue. When attempting to enter repair mode, it's found that it cannot be entered (due to lack of repair data display). Simply start the program to enter repair mode, then press "5" and "0" keys, and find that the machine works normally, thus confirming it's indeed a data problem. After adjusting all parameters, the fault is resolved.
Content transferred from; Beijing Skyworth TV after-sales service hotline http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3687333.