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General discussion

Two different LN52A850 sets died, Suggestions? T/S tips?

Mar 19, 2009 9:27AM PDT

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?

Discussion is locked

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dead sets
Mar 19, 2009 11:53PM PDT

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?

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dead sets
Mar 20, 2009 6:40AM PDT

Fellas,

First of all, I'm sorry to hear you're having trouble with the sets. There is no widespread issue that I'm aware of, but it's entirely possible for two like (or identical) sets to have the same symptom.

The authorized repair should replace any parts that need to be replaced free of charge for the duration of the warranty. If you register your set online, you also get 3 months additional warranty on top of what you have - so I would recommend doing that also. (Just a friendly tip).

I'm not sure if it's a board replacement, or a power supply issue, but whatever is causing this issue, we'll get it fixed up.

Keep me posted.

--HDTech

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repairs
Mar 21, 2009 8:53AM PDT

Well, the TV guys came today while my wife was home. When I got home, no TV. Seems they need to take it back to the shop to troubleshoot. I would have thought they could do that here and return with whatever part needs to be replaced. Now I have a 13" TV sitting where my 37" used to be and am watching with binoculars........... Sad

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Could it be a power issue?
Mar 21, 2009 12:12PM PDT

As stated in my original post I'd like to eliminate the possible power problem, but I'm not sure where else to go, troubleshooting wise. I've changed sockets and switches in the entire house after the first Samsung LN52A850 died, and I've checked the polarity of every socket as well as read out to power coming from the sockets with the kids running around the house turning everything on and off with a steady 121vac after the second one died.

I was thinking that maybe a possible power spike was the cause of the issue, but my surge protectors should have taken care of it. Would buying one of those power filtering surge protectors solve the problem, or posibly an APS? I'm out of Ideas.

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Call your local PUD (power company)
Mar 21, 2009 5:45PM PDT

If you are worried about the voltage at the outlet you have your TV plugged into, you will have to call an electrician to check it. Also, the voltage you measured is with no load. If your wiring is bad, the voltage could drop when you attach a load (such as a TV). But 121v is only .8% over 120v which I would guess is much less then the tolerance allowed by your PUD (assuming your meter is that accurate).

Some of the more advanced surge protectors/filters now have LCD readouts to tell you your line voltage, current draw, and some even tell you how dirty your power is.

Make sure the circuit you have your TV plugged into does not power anything with large motors, or other big energy users (such as refrigerators, compresses, microwaves, heaters, etc) as these can cause power dips or spikes when they turn on or off.

Also, what is an APS?

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I meant an APC UPS ...
Mar 22, 2009 5:26AM PDT

I ment one of APC's battery back-up / surge protector / power conditioner things. APC + UPS = APS lol...

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Repair guy came, could not fix...
Mar 24, 2009 8:23AM PDT

The Samsung repair man finally came by today to try and repair the TV but could not. He replaced the main board (with all the component inputs) to no avail. He said the next step is to replace the entire panel. I told him that I want to rule out the power in my house and he looked at my surge protector and said it was sufficiant and more than capable of stopping damage from occuring. He told me I simply had bad luck with both sets. Incidently it's the same repairman who tried to fix the first set.

The surge protector has 330 VAC Protection Clamping Voltage 15A Current Rating, -70dB EMI/RFI Noise Reduction, 74kA Max Surge Current with a 1,110 Joules Single Pulse Energy Rating capable of handleing up to 150VAC continuous power at 50/60Hz.

I suppose I'll wait until the set is fixed and see what happens.

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Repair guy came, could not fix...
Mar 24, 2009 4:29PM PDT

raceryan,

I'm not convinced that it'd be a power problem on your description. Your joule rating isn't bad, and I suspect that if there was a significant spike that actually hit the TV, it wouldn't start at all.

That said, 2 out of 2 is not a good ratio. That said, I suspect the bad part will be replaced with a part that works properly and you'll be good to go. If not, I'll be here to assist. In the meantime, I apologize that you can't use your television in the meantime.

Please keep me posted.

--HDTech

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same problem
Mar 25, 2009 12:50PM PDT

Was watching my Samsung ln52a850 on Sunday when the screen went black. Geek squad repair man came out today to look at it and after he spoke with Samsung Tech concluded it is probably the inverters. Ordered inverters and main board just in case. Hopefully will be working next Friday. I am not real happy.

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I'm definately not happy now...
Mar 26, 2009 6:35AM PDT

I feel you. The more I look online, the more posts I find with people having the same problem with this model. I contacted the Samsung complaint department and wrote about my experience with the 2 TV's and all I got back was a standard auto reply saying:

"We are very sorry to hear about the trouble you have had with this LN52A850. We feel that we make a high quality product that is, in most cases, free of defects....we do take these concerns seriously..."

Seriously huh? I want my money back to get a Sony XBR now. What's going to happen when the TV craps out again, god forbid it happens 366 days after purchase...I'm out 2500$?? No thank you. The TV looks gorgeous.....when it works.

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New Inverters Fixed Problem
Apr 6, 2009 11:12AM PDT

The Geek Squad came to the house with the new inverters and the tv picture fired right up. New version inverters are blue instead of green. Hope the fix lasts.

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Good to hear!
Apr 6, 2009 11:20AM PDT

Keep me posted!

--HDTech

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TV Fixed with new main panel
Mar 30, 2009 11:22AM PDT

Okay, for those who care my "No Video with Audio still working" gripe was fixed by Samsung with a new Main Panel (entire screen assembly) today. The tech still says it was bad luck with these two sets. We'll see about that in 2 months. (saw those new LED TV's and I wished I'd have waited....)

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Main Board....
Mar 30, 2009 6:36PM PDT

raceryan,

Let me know how it works out. If you have any further issues, let me know and I'll see what I can do to assist. I don't like to see anyone unsatisfied or worried about their unit.

--HDTech

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new main board
Mar 30, 2009 11:51PM PDT

My LN37A550 should be arriving tonight and I am advised that they also had to replace the main board. Hopefully, that resolves my problem.

If Samsung contracts these boards out, I really hope they are getting reimbursement. Sounds like they got a whole batch of bad boards. Maybe a new supplier is indicated.

I wonder, are the same boards used in all of the A550 series?