Observation of the machine automatically lights up two red light red but the boot and normal after the shutdown. After the distortion of the pillow, check the pillow school circuit found a cement resistance 2W10 open circuit, normal after replacement. But the starting about ten to thirty minutes after the white screen phenomenon, light, sound normal, the image is magnified not clearly carved territory, only white, but also remote control station.
The investigation 12V power output circuit diagram and the possible variation of some small value of high power resistance were tested were not found the problem. As the sound is normal, the power source should be normal. According to the failure phenomenon concluded that the video amplifier parts, when I turn on the TV chassis cover, the failure phenomenon does not appear. Of course, I am not free every day to repair the machine, I am not a professional machine repair personnel. I suspect that the fault is a video signal generated in front of weld after interruption. But when a fault is discovered has retrace line not too clear, it may be treated without 230V tube collector voltage to the ground caused. I had to open the machine cover after boot waiting for fault test voltage, waiting for nearly an hour fault finally reproduction, I hurried to measure depending on the voltage collector tube, then only 12V around. Carefully check the 230V power supply circuit, see between the circuit board and the main board of a cable has poor contact, simple figure out carefully insert fault will no longer appear.