I have an ongoing problem with this TV set that I can not seem to solve on my own. Initially about a month ago, I turned on the set and after an hour or so it shut down. I unpluged & repluged and it powered back on & stayed on. The next day I turn it on & it shut down. Afterwards, I could hear a faint "ticking" sound. After viewing numerous posts in various TV forums, I ran across a post in this forum by someone named "pasty" who advised the following: "common for the horizontal output to short in these models is a 2sc3892a which shorts because of a 10uf 160V filter capicator on the primary of the H drive transformer deteriorates & distorts the Waveforms causing H out transistor to overheat & short". I also found another solution in another TV forum that advises that a 22uf@50V cap located at C871 on the power supply board is also known to cause problems. I have also found a solution that said to also replace the IC regulator along with the HOT. To summarize, I have replaced the HOT, the IC regulator, and the following electrolytic caps: a 22uf@50V on circuit # C871 on power supply board, and a 10uf@160V on circuit # C416 on the same board where the H.O.T. is located. Now then, after installing the above new parts, the TV powered up with a wonderful clear & crisp picture, but after 15 minutes it shut down. After it shut down there was NO "ticking" sound. I unplugged & replugged & it again powered on but again shut down after 15 minutes. The HOT tests good with my DMM, and I am at wits end trying to figure what is causing the TV to shut down. I am looking for a straight foward solution to help solve my problem. I have limited experience, therfore a step by step solution would be most appreciated!! I thank you.
The cuestion is if every time it shut down you have the hot shorted,or not. have measure the flyback/yoke/Hot working current? it must be under 0.6Amp ,if is greater something is wrong and cause overheating.Normally I touch with my fingers to "measure" the temperature. and what about the Micro?.there´s one pin that control power on/off ,is it good-solid data or is crazy . micro gets hot, have a correct 5Volt on its VDD pin. lot of cuestion that I hope helps you!!!
Posted on Jul 13, 2007
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I suspect the IC regulator as it has lousy connections by a TV repairman. I have checked all other connections & they look good. There is a lot of damage on that part of the board where the IC regulator is. It must have burnt out sometime in the past. I think I have maybe a few bad resistors somewhere, but without knowing the values upfront & have to go by the colors on each will take me forever!!
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