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Discussion Starter #1
Hi all,

In reading the DIY thread, I believe I have a good idea of what needs to be done to correct convergence issues on my 10-year-old prized Toshiba 50H82. Heeding the advice of the article, though, I'd like to confirm that what I am experiencing can be traced to the convergence ICs.

After about 10 minutes of use last week, my set suddenly went "3D". It is very clear that the green color is "off" from the red and blue, creating a ghosted, 3D-like image.

The autofocus on the TV fails when the button is pushed (returns an error). The red and blue can still be adjusted in both directions when entering the user convergence menu. The 9-point convergence screen clearly shows a green "+" shifted to the right of the red and blue "+" (which are still on top of each other).

As I understand it, the green convergence is the "baseline" for this set. Meaning, it is not user-adjustable and the red and blue are adjusted off of it.

Since I have good red and blue control, and they are well aligned, is this still possible an issue with the convergence ICs? I wasn't sure if they control all three colors (even the green which is not user-adjustable) or only red and blue.

Thanks in advance. Looking forward to tackling this repair. Replaced the remote sensor within the unit about a year ago which was also a satisfying repair.

Thanks!
 

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Actually, in the service menu, you do have control over the green. You should get a service manual and be prepared to adjust the dynamic convergence once you resolve the problem. The "autofocus" is not really very "auto". It simply adjusts the convergence back to wherever the last value stored might be, relative to the sensors.

Before going any further, I would check for bad solder connections and blocked sensors on the screen. These sets commonly have bad connections throughout the main board which can either cause misconvergence or cause an IC failure.

If you do not feel confident troubleshooting, soldering, or doing convergence adjustments, I suggest you find a professional that does. Many people repair these themselves if they have these skills.
 

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Actually, in the service menu, you do have control over the green. You should get a service manual and be prepared to adjust the dynamic convergence once you resolve the problem. The "autofocus" is not really very "auto". It simply adjusts the convergence back to wherever the last value stored might be, relative to the sensors.

Before going any further, I would check for bad solder connections and blocked sensors on the screen. These sets commonly have bad connections throughout the main board which can either cause misconvergence or cause an IC failure.

If you do not feel confident troubleshooting, soldering, or doing convergence adjustments, I suggest you find a professional that does. Many people repair these themselves if they have these skills.
Thanks. I was aware the service menu had some more adjustment than the user menu, but at the same time, with nothing else having changed, I did not want to just jump in and start making adjustments.

I opened the TV up for the first time and the quantity of dust was overwhelming. Cleaning it all up now to get a better look...

Any key, specific points to look at for the bad solder connections and blocked sensors?

Thanks!
 

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Check all of the sensors around the screen. Sometimes spider webs and dust can create a problem.

As for solder joints, if you have good soldering skills and good equipment, I just resolder any joint that looks suspicious. Anything with a ring crack, or anything that for any reason does not look right. Be careful not to bridge any joints.
 

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Discussion Starter #5
Check all of the sensors around the screen. Sometimes spider webs and dust can create a problem.

As for solder joints, if you have good soldering skills and good equipment, I just resolder any joint that looks suspicious. Anything with a ring crack, or anything that for any reason does not look right. Be careful not to bridge any joints.
Thanks. Would one expect the convergence to suddenly "go out" as I've described as a result of a sensor issue?Since red and blue move OK, I'm wondering if it makes sense to get in to the service menu and try the full 56-pt convergence set?
 

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Probably not caused by a sensor, but you can't count on the auto convergence if they are not clear.
I would not do any convergence beyond testing until it is fixed. If you cannot adjust the green in either H or V you either have a bad chip, open resistor, or bad solder joint. Most of the time that is.
 

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Discussion Starter #7
I jumped in to the 56-point convergence just to try to understand it and see if everything moved. I found that green will not adjust left to right. All other adjustments seem to work.
 

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Discussion Starter #8
For reference, this is what the green grid looks like in the service convergence adjustment. Red and blue are perfectly straight.

 
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