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Discussion Starter · #1 ·
I acquired this set with the hopes of repairing it. The initial problem was a series of wavy red lines across the top and bottom of the screen. After much research and testing it looked like a matter of replacing the bad STK392-110's with a new set.

After installing the new ic's it looked a little better but there was a large bow present in both the top and the bottom. I tested all the resistors around the ic's and all except this smallest ones are well within tolerance. The small 1.5, 1.8, 2.2 and 3.3 ones read 1.9, 2.1, 2.5 and 3.6 respectively. These appear to be outside the 5% tolerance however I am unsure if my multimeter is accurate down that low. This was done with one end disconnected.

Beyond that the only other obvious problem is this unknown component on the power/def pwb. Its a small, round green item that appears to be covered in sugar. The top is waxy to the touch. I scraped it off in an attempt to read the numbers. All I am able to read is 180k L4. The other similar looking components are all smooth and clean. I assume this part is bad and need replacement but despite much research it remains a mystery to me.

I have attached two pictures of my convergence problem and the suspect component. Any assistance would be greatly appreciated.

Passive circuit component Electronics Capacitor Electronic component Circuit component


Display device Visual effect lighting Technology Screen Square
 

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Have you tried to adjust the convergence?

It is unlikely that your mystery component is bad. It is a coil and sometimes they are covered in wax that will look this way. Your multimeter is almost certainly not very accurate at low ohms and while in the circuit you cannot measure accurately anyway.

Read the first ten posts of the convergence repair sticky very carefully:

http://www.hometheatershack.com/for.../5600-crt-based-rptv-convergence-repairs.html
 

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Discussion Starter · #3 ·
Yes, I spent hours Sunday afternoon. I managed to get the middle to look decent but the bottom and top are a problem. The bow at the top and bottom is normal on the convergence screen? The pattern runs off the screen so its hard to adjust. Not to mention its just one big sin wave that has to be adjusted line by line back and forth. I have probably spent 4 or 5 hours adjusting it so far.

If all of this sounds normal then so be it. Is there anything else that might help me complete this. And yes, I have read the sticky and hundreds of other posts. I can generally google and problem and eventually fix it but this one just didnt seem quite right to be. Your information is very helpful and for that I thank you. The whole site has been a great aide in this whole process. I am just trying to make sure im on the right track and not wasting my time on a bigger problem.
 

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Plain ole user
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If you can adjust it, then the convergence amps are likely working normally. It looks like you have some corrupt data and may need to start from scratch to straighten out the geometry.
 

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The process varies with brands and models. I would start with the service manual.
 
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