| Samsung tv has sound but no picture I have a 40 incg samsung lcd that the picture currently went out on. The tv still has sound but there is no picture. The strange thing is that when I press on the power supply cord on the back of the tv, the picture will reappear however as soon as I release the pressure, the picture turns off again. I tried replacing the power supply chord but had no luck fixing the problem. Also thought it could be the backlight inverter, but I replaced it as well with no luck. I was told that it couldn't be the power supply board because there is still sound. Any ideas?? |
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 UHFAll static, all day, ForeverPremium,MVM
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| said by :I was told that it couldn't be the power supply board because there is still sound. Any ideas??
Not necessarily true. It certainly sounds like a power supply board issue to me, probably a cold solder joint somewhere on that board, and pressing on the connector flexes the board enough to make that bad joint make contact. |
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| reply to gthreat24
said by :when I press on the power supply cord on the back of the tv, the picture will reappear however as soon as I release the pressure, the picture turns off again.
That's a bad connection, be a cold solder joint, broken wire, delaminated trace, etc. You need to remove the cover and find it. Sometimes a close visual inspection is enough.
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TheMGPremium
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Canada
kudos:2 | said by aurgathor:Sometimes a close visual inspection is enough.
Just a week ago I was troubleshooting an SMPS out of a PA speaker amplifier. It would cut out whenever the board was flexed or even just the tiniest vibration.
Looked all over the board for cold solder joints: nothing. What the heck, lets re-flow all the solder connections anyways. No luck. Hmmmmm, maybe a component itself is at fault? I started gently tapping on each component hoping to find the culprit, I was just about ready to give up, when out of the corner of my eye I saw a tiny blue spark near the base of the transformer. As it turned out, one of the windings had broken off when it connect to the solder pin, but was just barely making contact.
Interesting thing is, it seems that two speakers are exhibiting the same fault. I wonder if the winding is being nicked in the manufacturing of the transformer and over time the vibrations cause it to break.
Intermittent problems can be easy or quite difficult to figure out. |
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| reply to aurgathor
I checked around for cold solder joints but don't see anything unusual. I will resolder all suspicious looking joints and if that fails I'll probably just order a new one.. Thanks for the help |
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| reply to gthreat24
with the power supply cover off, using a plastic tool, press on the board in different spots, and see what area is most sensitive, intensify your search there.. and using that plastic tool, tap on various components, the one that is most sensitive is the one causing the problem. remember that transformers and chokes can have bad connections where the wires connect to the pins.. |
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