Our Samsung HDTV LN-T4661F was making that clicking noise you find so many people complaining about on the Internet. Since the moment I heard it I said this was a capacitor related problem resulting in a non stabilized enough direct current causing on and off switching of an internal relay which ultimately is the one responsible for the noise. Relays are used to drive with low voltage and currents sources of higher voltage and current in other words control high power with low power.
The TV started doing a couple of clicks instead of just one click and within weeks it deteriorated to end up taking minutes to turn off. I was sure this was a capacitor related problem as electrolytic capacitors start leaking lowering their capacity and as they continue to be used their capacity only goes lower (after all leaking cannot be stopped).
A simple inspection in the Power supply board will give you the culprit in these cases. Commonly the capacitor will appear open on top of it. Electronic suppliers learned a while ago (after some explosions) to make a weak aluminium top that will break apart acting as a escape leaking valve.
But I wanted to run this by Samsung so I called them just to get as response that my warranty had expired. I decided to take care of it myself. So I took the opportunity my brother visited us for Thanksgiving and he helped me taking the TV to the dining table. We placed it screen facing down (my brother's recommendation) and as you can see from the picture I located the power supply on the left of the board:
I opened the power board and I was right. Three capacitors were broken. Look at the three in the middle on your left:
However the most important part of this story is what I learned when I open that TV. Basically a factory mistake was the culprit for this problem. A capacitor was placed in reversed polarity causing the device to malfunction of course. If you see the previous picture you will notice the bottom of the three capacitors has the negative sign pointing to the left and that is a factory mounting mistake. As you see below its negative polarity must be facing right instead:
This is definitely something Samsung should fix for free. I would not be surprised of people getting explosion inside of their TVs as it is demonstrated here. One of those experiments we use to make in the 80's.
It was thanksgiving week so I pulled an old VCR and I took capacitors from it for the repair:
They were not the same capacity but as long as the capacity is bigger they should work as they work with linear current basically stabilizing the alternate rips, the bigger the capacity the better (within certain margins as you do not want to demand too much current in one shot on power on). The other very important metric is the voltage. The capacitor must be able to handle the voltage and the ones I found were at least for one of them less voltage than the original. However in this case I was lucky because Samsung had placed capacitors that handled voltage bigger than the one in the board. An inspection of the real voltages in the board (following the PCB routes to the power distribution connector) allowed me to determine it was OK to use those as replacements.
I am impressed how customer support treats everybody as if we were all the same. I am telling you I am an electronic engineer and for what is worth I was just trying to help Samsung when I told them they better come to my house and repair the TV for free as this was a factory problem I read about on the Internet and as a profesional of the field I was able to confirm. Hopefully you will make your Samsung TV inspected by a professional or be lucky enough to have current warranty. If not perhaps you will take advantage of this post and call Samsung and they'll probably make their mind especially if they understand there is a real risk of an unwanted explosion inside your TV.
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