Hi, obviously you had some documentation of the circuit boards or even a service manual. I am not so lucky. I purchased my SONY KP46 several years ago in the US, but later moved to Germany and had the KP46 running for a while, using PAL to NTSC converters and a 230V/110V transformer. But out of a sudden, some strange noise like "crickle-crackle" and the picture went bläck. After a few weeks I was able to get it working for another couple of hours, but then again, this strange noise and then it stopped working. I guess it has some thing to do with the power supply unit, but no circuit diagram is available. The German repair shops don't have them either, because the KP46 für NTSC standard is not available here. Any idea ? Klaus