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Discussion Starter · #1 ·
The television was free. I brought it home and noticed that it seems like the colours were not lining up correctly. Is this a common problem with rear projection tv's? Is it an expensive fix? Easy Fix? I opened up the back and adjusted the lenses the best I could, but it seems like the green light and lens bends towards the corners of the display. Please give any input you can, the television was free, its a 52 inch, and if it can be fixed fairly easily I would like to attempt it. Thank you!
 

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Quote:
Originally Posted by svendawgg /forum/post/20839683


The television was free. I brought it home and noticed that it seems like the colours were not lining up correctly. Is this a common problem with rear projection tv's? Is it an expensive fix? Easy Fix? I opened up the back and adjusted the lenses the best I could, but it seems like the green light and lens bends towards the corners of the display. Please give any input you can, the television was free, its a 52 inch, and if it can be fixed fairly easily I would like to attempt it. Thank you!

You didn't say the model or even the technology, but it sounds like a three-CRT rear projection. If that is the case, get the model number and try Mr.Bob's thread called 'Don't Dump Your CRT RPTV' at http://www.avsforum.com/avs-vb/showt...95922&page=310


A photo of what the screen looks like will help.
 

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Discussion Starter · #5 ·
Hello, Still looking for assistance with this set. I purchased a service manual online for it, and have opened it up. I can get the center of the television to line up and look sharp, but the colors separate along the corners. I am brand new at this, and am wondering if it could be an issue with parts, or if a calibration may do the trick. Thanks!
 

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If you can't get the convergence set correctly with a service menu calibration then it's possible that the 'convergence circuit' is failing.


I have an old Toshiba 42" 1080i CRT RPTV and a couple of years ago I turned it on to find that one colour was completely out of line with the rest. I tried to fix it through the convergence menus, but after some additional research I found that it's a common problem on alot of the older sets that the circuit board that handles conversion tends to fail.


I was quoted about $300 for a tech to come to my place and replace the circuit, or if you're handy you can do it yourself for less than $50 in parts.


I'm sure there's a thread on here somewhere, but here's a link to a thread on another forum that discusses the problem and how to fix it DIY.

http://www.digitalhome.ca/forum/show...ht=convergence
 

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Discussion Starter · #7 ·
Thanks for the info! I was just lookin for something to tinker with, and figured if it was something I could do manually I would give it a shot. The person I got it from told me that the right corner was the only spot out of focus. But by the time I got it home (bumpy truck ride, up a set of stairs, etc) the thing was completely out of wack. Ill keep tinkering with it though... was just hoping that I would be able to adjust it somehow.
 

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Well your problem doesn't look quite as severe as mine or some of the other examples I've seen, so it's possible that the 'guns' were physically misaligned during transport. However it's also possible that this is just the first sign of a failing IC...


Good luck and hope you get it fixed, these sets still look great when setup correctly!
 

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Discussion Starter · #9 ·
Thanks, based on the photo's ive seen, and what I have been reading, I think I can probably go home and solve the issue I am having. I am able to focus everything, and make the center of the screen look crystal clear. Like I said, it is the corners that become out of wack. The service manual explains a process that you can use to line things up again. Hopefully that does the trick. Ill just go in behind the tv again and focus and center things up the best I can, then use the remote and try to align the corners. Thats what I understand I am able to do from what I read in the manual anyhow!
 

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If your problem is anything like ours was (it should be, it looked almost identical to ours based on the symptoms in the photos you had), you'll either need to resolder or replace the convergence ICs inside the set. From what I understand, over time, the heat inside these builds up and either causes or "helps move problems along for" cold solder joints where the convergence ICs attach to the board. When one or some of these points either only partially or fully stops making connection, massive convergence failure (like what is pictured) occurs. For many people who have seen the problem start overnight can still sometimes fix it the "cheap way" by either bumping the base of the set or taking the back off and physically tapping the IC (or ICs) in question. If doing any of that provides a temporary remedy for the picture and you're not afraid of diving into the set, resolder the ICs.


If left this way for too long on, the ICs will eventually fail and either "stick" that way (which no amount of resoldering will fix) or become a short circuit and cause the set to not want to start up at all. Unfortunately, ours was the latter. The community here seems to strongly recommend replacing the ICs, if necessary, only with genuine Sanyo brand ICs, which can only be purchased from a small handful of stores for a slightly higher price. I don't remember for sure where we got ours (it's somewhere in that "Don't dump your CRT RPTV thread within the last 25-40 pages or so. Between Late may and Mid to late June), but we found several coupons to help the price out a bit, and with UPS shipping, it only came out to around $26 for a pair of ICs.


You can also buy an entire convergence board in some cases for some unholy 70-100+ dollar price tag, which is why most people save their money and get out (or learn how to use, in my case) their soldering irons and just replace the ICs.


Back to your other comment - the only thing the service guide will help you with is finding out which ICs originally came with your set (their part number can be put into an internet search, it'll be something like "STK392-110"). Some sets will take higher class ICs than were originally shipped with them. Our Mitsubishi WS-48311 originally had 110s, but Mr. Bob actually recommended to us the STK392-180s, and they've been working out great (they were actually cheaper on the site we ordered them from than the 110s would've been).


If I were you, I'd try "tapping" and "bumping" the ICs, and if the picture momentarily "snaps" to normal, shut off the set and just heat up those solder joints again. If not, then it's probably too far gone and you'll want to purchase another set of ICs. To find out the best kind and where to get them, post in Mr. Bob's "Don't Dump your CRT RPTV" thread, and the users more familiar with the "ins n outs" of "what convergence ICs work well with what" will help you figure out what ICs you need in no time to get your Sony running great again. When you're done, you can celebrate by buying some component cables for your Xbox 360 (if you don't already have some) and watching it in HD!


Good Luck!


- 2 Bunny


PS: From what I read, it almost sounded like you were venturing into the service menu and also playing with the optical focus. Carelessness with either of those can render your set useless, so try to fix the problem at hand first before you mess with those.
 

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Discussion Starter · #11 ·
Good Morning! I just finished reading the previous post. You were right, I was tinkering with the optical focus (for like 3 days now). I didn't have a chance to get back here before today to check the post. The set is now crisp and clear, but I still couldnt get everything to line up right in the top left corner, and bottom right. I know now that it is definately something that will need to be repaired. I did find a replacement set though; as luck would have it, someone from work had an identical set sitting around his house collecting dust. He says it is aligned properly, just a little "dark". So I will be using his instead of the one I have been tinkering with for the past few days. Maybe ill have two fully functioning sets soon... who knows. Been learning lots about this technology lately though. Pretty interesting stuff.
 

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Quote:
Originally Posted by svendawgg /forum/post/20856867


Good Morning! I just finished reading the previous post. You were right, I was tinkering with the optical focus (for like 3 days now). I didn't have a chance to get back here before today to check the post. The set is now crisp and clear, but I still couldnt get everything to line up right in the top left corner, and bottom right. I know now that it is definately something that will need to be repaired. I did find a replacement set though; as luck would have it, someone from work had an identical set sitting around his house collecting dust. He says it is aligned properly, just a little "dark". So I will be using his instead of the one I have been tinkering with for the past few days. Maybe ill have two fully functioning sets soon... who knows. Been learning lots about this technology lately though. Pretty interesting stuff.

Very interesting indeed. If you can drop 26 dollars on ICs, you could have multiple monitors!
(Or use one for Xbox 360 and one as a monitor, or whatever else you want)


- 2 Bunny
 

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Quote:
Originally Posted by svendawgg /forum/post/20842169


Thanks, based on the photo's ive seen, and what I have been reading, I think I can probably go home and solve the issue I am having. I am able to focus everything, and make the center of the screen look crystal clear. Like I said, it is the corners that become out of wack. The service manual explains a process that you can use to line things up again. Hopefully that does the trick. Ill just go in behind the tv again and focus and center things up the best I can, then use the remote and try to align the corners. Thats what I understand I am able to do from what I read in the manual anyhow!

Your convergence is off. Have you tried pressing the "flash focus" button on the tv, behind the vertical door under the screen? This was supposed to self-converge the tv.


If this doesn't work you could have success doing the manual convergence procedure in the service menu as outlined in your service manual.
 

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Discussion Starter · #15 ·
I havent done anything new since my last post. I havent had a chance to get over to the guys house to pick up the new television because hes been ill for the past few days. But I will probably pick it up tomorrow. I did try the flash focus (first thing I did) and it did align the red and blue pretty much perfectly, but still left the green looking way off across the entire set. So I then figured I had nothing to lose because the set was free, so I began tearing it apart. Started with tinkering with the lenses and bulbs themselves, those focus knobs underneith the lenses. Then when that didnt work I came on here. I then learned that I probably should have left the focus knobs alone.


But while tinkering inside there, I was able to wipe the lenses off using a microfiber cloth; This brightened the tv up a bit, and I was able to sharpen the picture up a little bit. Actually while im here, Ill draw up a little sketch of the strange parts of the television.


After coming on here, I downloaded the service manual, tried to manually align the colors. I was able to zoom way in using the back, then zoom back out using the software inside the tv. I came up with something that was better, although still hardly functional when gaming. I was really hoping to be able to fix the set without actually tearing the guts out of the thing. But now that the second tv is available, I think i will give it a shot. Unless I get zapped, I really have nothing to lose!


Anyhow, like I said, the best shot of what the television looks like, to the best of my memory.

 

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Quote:
Originally Posted by svendawgg /forum/post/20869839


I havent done anything new since my last post. I havent had a chance to get over to the guys house to pick up the new television because hes been ill for the past few days. But I will probably pick it up tomorrow. I did try the flash focus (first thing I did) and it did align the red and blue pretty much perfectly, but still left the green looking way off across the entire set.

"Flash focus" is just Sony's name for the "roughly do the convergence for me" mode, which usually isn't all that good. Your problem is probably with the convergence ICs, did you check those at all?

Quote:
Originally Posted by svendawgg /forum/post/20869839


. So I then figured I had nothing to lose because the set was free, so I began tearing it apart. Started with tinkering with the lenses and bulbs themselves, those focus knobs underneith the lenses. Then when that didnt work I came on here. I then learned that I probably should have left the focus knobs alone.

Definitely want to be careful in there as from what I understand, there's quite a bit of high voltage. Also, there are no lamps inside of CRT Projection units of any kind. You should probably get the convergence ICs fixed up first before you do any kind of focusing, as you'll have an easier time being able to tell what you are doing.

Quote:
Originally Posted by svendawgg /forum/post/20869839


After coming on here, I downloaded the service manual, tried to manually align the colors. I was able to zoom way in using the back, then zoom back out using the software inside the tv. I came up with something that was better, although still hardly functional when gaming. I was really hoping to be able to fix the set without actually tearing the guts out of the thing. But now that the second tv is available, I think i will give it a shot. Unless I get zapped, I really have nothing to lose!


Anyhow, like I said, the best shot of what the television looks like, to the best of my memory.


Even in the 64 point convergence, you will be unable to correctly align the set since the Convergence ICs have failed. To fix it, you don't have to take the whole set apart at all. All you've got to do is resolder or replace the convergence ICs (see my post above). That's all that is wrong. Nothing is "out of adjustment" or "broken in the lamp" like the people giving these away on Craiglist would like to deceive you into thinking (I've seen plenty of devious CLers try that
).


Good Luck, and let us know how it goes.


- 2 Bunny
 
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