Panasonic PT-47WX53 G

I replaced the ic's. The green bow is gone but now I cant converge the red to the right. Di I mis solder on of the ic pins or could it be something else?

My TV too got a "bow" at the bottom of the screen. Seem like many suggested replacing this STK chip and also it's $10/each so I went ahead buy 2 to replace the 2 in my TV.

Below is a pic of the inside of my projector TV with the STK-392-110 circled in green and as you can see it is easy to ID due to the HUGE heat sink that it mount on to help dissipate the heat. (sorry for the small size since Fixya limit the file size to 150KB)



I unplugged the TV for more then 3 days and that seem to discharged most of the components.

So here are the steps I take to do the fixing.
1) Before I even order the chip I open it up to verify the part number and it was STK-392-110. Did many research try to find as much as I could about this chip and make sure I order the correct one... so I made the order. While waiting for the product, the TV had been unplug ever since.

2) Well, in order to even get to the inside I need to dismount the back panel. So it had stayed open ever since, of cause out of reach of children.

3) The components arrived and I prepared:
- soldering iron
- solder
- heat sink compound (used mainly to fill in a good gap for CPU heatsink inside computer)
- and solder sucker (the sucker later I found to be useless).
- Flashlights
- Screw driver
- Plier.

O, and my brother offer his help which I found to be very useful. My 2 hands weren't enough to do this work.

4) Removed the 4 screws which I marked with the yellow arrow inside the pic.

5) I didn't want to remove any cable afraid that it might create other problems but had to remove about 3 cables to make it easier to lift and move the board around a little while fixing.

6) Removed 4 screws that mount the chip to it's heat sink using a very short screwdriver. Very little space to work with.

7) It was extremely hard to remove the old chip with the board still cabled to the TV. Many times I was tempted to disconnect all the cables. What prevent me from doing so was I couldn't think of a good way to document all the cables that I disconnect and there are just too many (IMO). I did take many pics just in case.
Anyway, what I did might not be the best way but it worked. I tip the chip back and forth to weaken the pins to a point that it broke. It took forever but it did work. After the chip broke off that I can desolder and remove each pin with the plier. Again with the little space to work with that made me want to remove it from the TV. The pins holes were still very messy and full of solder. My brother came up with a way to clean the hole using stripped wires. When the stranded strip wires touch the liquid solder, it help suck the solder out of the hole. I'm sure there are better ways to clean the holes.

8) We had a little hard time putting the new chip in b/c a few pins bended a little and not align with the holes on board. And when added the compound to the chip, it made it even harder since now the chip need to stay away from the heat sink or else it'll stick to the heatsink. Finally we got the new chip in the holes on the PCB with the compound and all, so it just a matter of screwing the chip onto this heat sink.
9) Turn on TV and pic is 99% perfect again. Why not 100% U might ask.. b/c I saw a tiny out of align colors on the left of the screen. Not very noticeable but I can see it when I pay close attention.

Cost for the two chips were $20 included shipping. Hey, it's a lot cheaper then buy new TV and only 2 chips trashed instead of the entire TV. Anyway, I think I knew which chip went bad. Because one chip had hardly any of the compound. This compound help the transfer of heat to the heat sink.

Hope this help someone.

Convergence amp ics are faulty.they start with stk numbers large in size,