My Sony KP57HW40 plays fine for about 1/2 hour, then begins turning reddish color, to a bright red flash, back to great piture, with a repeat of the same process, becoming more frequent, until tv finally turns itself off. Any suggestions as I have not been able to find this type problem posted anywhere.
Initially i would say you have one of two possible problems, Either the 200 volt line is intermittent to the tube or the tube is shorting. If the tube is shorting it needs replaced, this is not a cheep repair. And as far as the other problem it could be that you have a bad focus block. To be honest i see more tubes that are bad then focus blocks. With that tv.You also have to remember that i am telling you this without seeing the tv, and my comments are directed at what i see the most, your problem could be different. It could be a problem with the neck module as well.There is one thing that you can try is to switch the neck modules around put the red on the green tube and the green on the red tube and see if you get a green flash or a red flash. if you get a green flash it is not the tube if you still get a red flash your tube is bad.
Thanks for the info. I have noticed that after it cuts off, it blinks 8 times, which I found out thru the internet search, was a diagnosis code for Sony repair. With 8 blinks it could be the audio or the flyback transformer or associate components in the high voltage circuits are defective on the D board. IS this consistent with your comments? I guess my real question would be if it is worth repairing. It was purchased in 02, with this problem being the first.
i did not look up 8 blink but if it is what you said about the flyback, it could be the tube. the flyback supplies the high voltage to the tube and if the tube is arching it could cause this. You might want to get a diagnosis, because it could be something other than what i have said. Without seeing the tv and diagnosing it myself i can only rely on what i have seen in the past, which may NOT apply to your problem.