Screen flashing I have a hitachi 57swx20b, 57" rear projection hd monitor. When the tv has just been turned on, everything is fine. As it warms up, the screen will begin to flash. The flashing is worse the darker the video is. In some of the video, it appears as if when the screen flashes, the convergence is off in the center of the screen. I had a sears repair man out to look at the set, and he said that he wasn't sure what the problem was, and that the tech dept. didn't have anything in their data base. He wanted to just start replacing parts until the problem was fixed. And info you can give me would be greatly appreciated. Thanks, Adam

Experienced SEARS Tech here to give you a possible solution to your problem. Your Hitachi set has been known to have CRT (Picture Tube) problems where there could be debri that may cause occasional grid shorts and produce the exact symptoms you are having. Here is a suggested test. If you are able to take off the front cover and access panel, you will notice three CRTs by the glass necks with purty rings mounted on them. Now VERY CAREFULLY tap on the glass necks of each tube one by one with a plastic object only!!! You will probably discover that one of the CRTs are causing the light show you are having. The best clue you gave was the "warms up" hint. Hope this info. helps.

Thats what gave TV repair peeps a bad name way back in the 70's and early 1980's as almost every set made had moduales and everybody and there brothers and sisters went into the TV repair buisness!! they would shotgun boards till the right one was found. Oh and itf it wasent the board , and lots of times it was external chassis moubnted parts I would get them in for repair as I did work for dealers. Man some of these sets were dog repairs too. Most so called techs didnt have a clue what they were doing. Your problem is a simple one but time consuming to find. Theres capacitor or capcitors that are bad in the sweep power supply and or the main power supply. When we got a set into the shop the first thing I would have an entry level tech do is test all of the maain caps in the sweep/main power supply with an esr type capacitor meter. I found that doing this solved 79% of the problems and stopped alot of recalls because of bad capacitors. After the tech tested all the capacitors and replaced the defective ones the chassis was tested and most the time reasembled and the set adjusted to specs. If the set had additional problems my pro techs would set up the chassis on a test jig and trouble shoot the problem. yes we had our share of dog type repairs BUT always fixed what we were su7pose to. we were noit stupid though .. If a set had multi problems like we found burnt traces or multible bad ICs we would call the customer top see if this set went out during a storm or a power surge. After a little coaxing Most customers would admite they forgot to tell us so then we decided or not if the set was worth the repair or not. find an authorized repair shop to service your set, not a set up like sears that hires students right out of electronic school, but dont get me wrong , its good that they are learning BUt shoud they do it at your experence??? Good Luck