samsung le32r73 picture problems

[andyfitz48]

Hi folks
The above TV startedhaving picture problems. After a few mins of use the picture would start breaking up until eventually it would freeze or go black
I took the back opp and 1 bad cap on the psu near the mainboard connector. I replaced that but after a few mins the cap bulged again and the picture went soon after. I replaced the cap again with a higher rated 1 and the tv worked came on and worked fine for about half an hourbut had no sound this time and then the picture went again.
Ive not had chance to take the back off again but im thinking the mainboard is at fault but could the mainboard cause the psu to fail?
I will upload photos tomorrow evening if need. Thanks

Andy

[Andrew F. Ali]

Re: samsung le32r73 picture problems

Test the Opto-isolators...one of them may be not sending feedback to the Power IC to regulate the voltage.

[andyfitz48]

Re: samsung le32r73 picture problems

Thanks for the pointer. I got hold of a working psu and fitted that but the problem persists so suspicion now falls on the mainboard.
As the picture is fine for a while from cold its looking like its heat related so the 1st thing I was going to do was take out the mainboard and look for dry solder joints. Is there anything which could cause the TV to fail once its warmed up? Cheers

Andy