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SAMSUNG LE37R88BD - dark picture - peak whites flaring

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200sx:
Hi everyone. Been searching for a repair forum for ages and stumbled across the site yesterday, and I must say that you all seem a very friendly, helpful bunch   :thumbup:
Been out of the repair game for 15 years so I know nothing about LCD. I've now bought a new TV but thought I may as well try and repair the Samsung instead of binning it.
The set is 3 years old and the problem started about 6 months ago. Initially all the peak whites started to crush and flare. I found that if I came out of Dynamic mode and backed off the contrast a bit, the picture was again acceptable, but not as good as before. I tried the service reset at this time but it didn't improve things. Things remained steady until about 10 days ago when the picture brightness suddenly halved while watching it. If I turn brightness up full, backlight full and contrast around 75, the picture is watchable but poor during dark scenes.
I've read loads about PSU capacitors failing prematurely and taking the eeprom with them. Do you think its worth replacing these? Can they cause problems as discribed? I'm still handy with a Fluke and a soldering iron - just lack the modern theory !!

TIA

sparky:
hi
do any of the elcos in psu look like
they have started bulging if so change
them and see how the pic  looks then
dave

200sx:

--- Quote from: sparky on January 07, 2011,14:25:44 ---hi
do any of the elcos in psu look like
they have started bulging if so change
them and see how the pic  looks then
dave

--- End quote ---

No, they don't - was the first thing I checked. Is it generally the 2 1000uf and 2 1500uf that cause probs or can it be any? I don't mind ordering a bucketload if it could be worthwhile ! Would be a cheap and easy fix   :c017:

sparky:
hi
have you checked the lead to screen drive panel(tcon)
post a pic of fault
dave

200sx:

--- Quote from: sparky on January 07, 2011,15:14:44 ---hi
have you checked the lead to screen drive panel(tcon)
post a pic of fault
dave

--- End quote ---

Sorry, I'm a bit lost with LCD jargon. Could you tell me which lead you refer to? As I said in my original post, although I was a repair Tech for 25 years, I haven't kept up with TV technology (work in IT Support nowadays). This is the first time I've ever had the back off an LCD lol.
The TV is in bits at the moment so I can't post a piccy of the fault. The picture is worse at switch on - dark but watchable. When its been on a while it gets very slightly brighter (but still not really acceptable). Contrast has to be backed off quite a way otherwise any peak whites flare out - like an over contrast situation - the flare becomes green tinged - sort of a glowing effect.. Had it been a CRT, I would be checking A1 voltage to see if I could wind it up a bit.
I really appreciate any advice you could give, but treat me gently, its been a while     :93:

cheers 

Dave

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