The standby light goes out when the TV is on. (You probably knew that.) My 37" 550 started with no picture and slowly progressed to a light green static with very loud static noise. It takes me a good 5 minutes of restarting to get it to work. Repair man will be out tomorrow to look at it. From what I have read in other posts, board replacements look likely. I hope that fixes it. I bought it online 4 months ago so return is not an option.
Moderators: What happens in that case, does the authorized repair guy replace it?
Anyone able to diagnose this? 1st my 10 year old Mittsubishi Big Screen Projection died and wouldn't power up anymore about 3 months after moving in to my new home. No big deal. New HDTV time. Got a great deal at Best buy for a new LN52A850 and moved it in to my entertainment center, but died one month later. While playing a video game the convergance on the left hand of the screen went way out of wack and had 3-5 images overlaid on only the left half of the screen. It would go away after turning the set off for a couple hours and then bad convergence would return after 20 min sometimes it would be good half the day. The TV source had no bearing on the issue. The Samsung repairman tried but couldn't fix it and suggested taking it back.
After a trip to Best Buy for a return, My replacement LN52A850 worked beautifuly until it died 3 days ago, after providing nearly 2 months of phenomanl picture. While watching a Blu-Ray the picture just went black, leaving only audio working. At first I thought the set timed out like when I turn my computer off before switching sources, but the standby light wasn't on. Furthur analysis reveals all sources no video, only audio.
What gives. I suspected something with the wall power, but I have had 2 different surge protectors one on each TV, replaced all switches and sockets in the house, also checked the polarity of every single socket in the house with a handheld polarity unit. All check good.
The power out of the sockets are a little high at 121VAC, but I have no way to check the frequency out for any Frequency hiccups. (plugged in alarm clock does not loose time) No other problems with any othe household electrical equipment have been noticed.
After searching online I have found 3 documented cases of the same discrepancy my second set is diagnosed with, leading me to think it just may be the Samsung model.
Any suggestions? After the repair guy fixes this current TV I'm going to get a powerline filter/surge protector (monstercable maybe but I'm hessitant thinking that a powerfilter is a little like a snake-oil hoax) I also have my power company coming out to check the feed. Anyone had a simillar problem or heard of a fix or troubleshooting method? I am not going to buy a new TV every 3 months. Have I just had some really bad luck with sets?

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