I have a Samsung HCP4752W Rear Projection TV (Chasis P59A) The colors are blurred and I have two semi circles at the top and bottom of the screen giving an hourglass effect, so reading all of the other posts I believe I have a convergence problem. I have replaced the STKs but the problem remained. Has anyone got any ideas?
I have the same model tv HC-P4752W. i have replaced BOTH convergence ics. i noticed in this post that absolutely noone mentioned to use the higher amperage STK392-040. the -040 is a 7 amp version of the -010(-010 is 5 amp) but the -040 is what any tv repairshop that knows thier stuff will reccommend. you can also use the STK392-020 which is the 6 amp version but i would highly suggest the -040 because theyre around 10/each on amazon give or take. DO NOT GET CLONES IF AVOIDABLE. ive not tried them myself but i heard from numerous other forums they do not last. i used oz freeze instead of the white paste for longetivity of the ics. NUMEROUS forums advise against the white stuff as the chips get HOT and youd be replacing again soon.so better stuff is good(freeze,ic diamond,arctic freeze) will not damage nothing. SOLDER CORRECTLY!!! do not splurge. its not hard to learn and will save you a huge headache. and as told to me by a tv tech on the phone, when getting resistors use atleast 1/2 watt maybee even 1 watt for the 3.9 ohms.(they look like 1/4 watters) bigger wattage units WILL NOT damage nothing except the lack of headaches:). and by all means you CAN get away with carbon film standard run of the mill resistors but they arent my first choice. use flameproof if possible they are dirt cheap. same for the 150 ohm ones. bigger wattage is better long as they fit and use flameproof ceramics if possible last resort carbon film. my set works near perfect but i still need to replace the resistors and it may need manual convergence.:)
if you follow the tips that i have passed onto you free of charge that were advised to myself by the professionals your repair will outlast the set itself.
I have the same covergence problem on same model. I have checked the 3.9ohm fusible resistors all twelve seem to be OK, they read exactly 3.9 +/-0.05 ohms. I don't suspect the 150 Ohm resistors since they seem to be normal ceramic resistors across the input and output of each channel of the STK chip. If they burn, there should be some kind of discoloration, which is not the case. I hope that changing the STK only will do me some favor of getting the unit back to operation. Is it OK to use the same conducting material as that used in PC microprocessors? How did you solve the V-Shape line problem, just in case I get it.
I have the same covergence problem on same model. I have checked the 3.9ohm fusible resistors all twelve seem to be OK, they read exactly 3.9 +/-0.05 ohms. I don't suspect the 150 Ohm resistors since they seem to be normal ceramic resistors across the input and output of each channel of the STK chip. If they burn, there should be some kind of discoloration, which is not the case.
I hope that changing the STK only will do me some favor of getting the unit back to operation. Is it OK to use the same conducting material as that used in PC microprocessors? How did you solve the V-Shape line problem, just in case I get it.
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Each convergence IC has a fusible link going to the IC. On the foil side of the board you will see the fuse size, usually 3.15a. Check both with an ohmmeter, like you would check a normal fuse. Replace the one that is open and that should take care of your problem. Good Luck.
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Thanks for the info. I replaced both ICs but the fault remained. I then found two 3.9 ohm resistors bad, so I replaced them and it fixed the convergence problem but I now have a vertical line running doen the centre of the screen and when a TV Channel is selected the line has different colours and a noticeable v-shape can be sen to the left of the vertical line. The line and V-shape look like some one has drawn on the screen with a whiteboard marker/pen. The lens, rear os the screen and mirror are clean. Has anyone got any ideas.
If you take the lower cover off the rear of the TV you will see two large circuit boards the one on the right handside looking from the rear is the board where the ICs are located. The ICs are part number STK392-010 you can see one without removing the circuit board, it's on the left hand corner and will have STK392-010 marked on it they are large in size. I got replacements from www.bdent.com. Take the board out (disconnect leads etc and remember where they came from etc). The IC's are soldered in to the board and are screwed onto the heatshrink and also have a compound on them for transferring the heat, you will need to order this aswell (bdent.com Part No. 120-5). The pico fuses are green in color and look like a resistor without the color coding. Also check the 3.9 ohm resistors and 150 Ohm (i think) resistors. They are located near the ICs the 3.9 ohm are grey in color and have the following color code orange, white, gold, gold white. Good luck.
I also have the same problem on my Samsung HC-P4752. I fixed it by replacing the 2 STK392-010 Chips. I also found two 3.9 ohm resistors that were open (R142 and R143) and replaced them. Once I reinstalled the sub board, I had to setup the convergence on my TV. However, I noticed that the Red Convergence would not move left or right but would move up or down. Is this the way it should be? How can I get the Red Grid to move left or right? My picture is about 95% working. There is something I'm missing when setting up the convergence.
same set replace ics ck res but the q 433 was bad put new one in gets hot???
how do u get into the service mode to adjust convergence ??
I have a blurred picture looks like a 3d effect what do u think it is i got a repair man to check it he said it might be the convergence problem and he haves to change the skt thing but im reading all the others posting . And he is also charging me 320 to fix it that why im tring to do myself...
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