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Discussion Starter #1
Hey guys,

So a few weeks ago my set turned off and returned the 3 blinking red light error code. After some research we decided to go inside and perform the convergence repair as is apparently standard with these older sets. We replaced the two IC STK392-110 chips with two new STK392-120 chips, and also the R7060 and R701 resistors as those were the only two that appeared damaged. The two aforementioned resistors are 0.27ohm 1 watt resistors but we were only able to find 0.27ohm 5watt resistors to replace them with (possible source of problem?). All 6 of the commonly replaced 2.2 ohm resistors that are in front of the convergence chips appear to be intact. Anyways after putting everything back into place our set powers up fine and stays on with no error codes. However, we have absolutely no picture. The bulbs simply do not seem to be fully powering up. Anybody else have a similar problem or any suggestions?
 

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Discussion Starter #3
Thanks for the quick response lcaillo. This is my first repair of this magnitude so I know that's definitely an option. I've decided to wait until tomorrow to open it again to get a fresh perspective and I'll update the post then.
 

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Discussion Starter #5
Hey lcaillo,

All wires are accounted for. Upon closer inspection though R7011 one of the resistors directly in front of the convergence chips and often identified a a possible failure in these repairs is definitely discolored. Would it make sense for the system to fully power up and not return an error message though if this resistor was in fact burnt out?
 

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I am not sure that an open resistor would cause no video. IIRC it would usually cause shut down and would likely damage an IC. Something else must have changed. You can pull the ICs and the set should run fine with no convergence correction. You will have no convergence, but you should get an image.

Maybe you cracked a solder joint moving the boards around. Not an uncommon issue. Did you adjust anything?
 

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Discussion Starter #7
That's definitely an option. I did all of the work without completely removing the board so something may have been dinged around. Hopefully I will get some time to sit down and check it all out tomorrow.
 

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Discussion Starter #8
Got a chance to open it again today. I replaced the possibly burned out resistor and took a while to really examine the soldering on the board. There did not seem to be any damaged joints but when I put it all back together and powered up the set the same problem occurred. To be a little specific from the back of the set when it is powered on the three bulbs are clearly glowing at the bottom but no light is coming out of the lamps above them. Any thoughts? Or perhaps any other information I could provide?
 

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Do you have scanning? Did you adjust the screen controls? Some sets are touchy about those controls.
 

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Discussion Starter #10
I tried to make some adjustments but to no avail. The t.v. doesn't even respond to changing the input. What do you mean by scanning? The set does have channel scanning but that's not really accessible without the menu even appearing.
 
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