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I guess I should first ask if convergence issues are a possible problem on tube based TV's, I think I've mostly read of them with respect to projections. Anyways, I'm trying to pinpoint my problem before I call out a "Tech" to fix it, I don't want him doing anymore than he has to. Also, if it's possible, are there any convergence test patterns you recommend.
 

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Convergence issues are definitely possible and improvable on tube-based TVs. The convergence tweaks made on my TV definitely helped. It may be trickier on some TVs than on others though.


I tried several different patterns on my HTPC, but found an array of 1 pixel white dots on a black background seemed to work best after noticing how apparent the convergence was in stars and city lights on Star Wars Episode II (@1080i I should add). A grid of white lines also helped. There's a pattern on the THX Optimizer (contained on many DVDs) similar to this, but it wasn't really detailed enough to make the minute adjustments I wanted. Something similar may be included on calibration disks like AVIA, or perhaps Video Essentials.


The problem manifested on my TV as a kind of general lack of clarity in the the image, and also red or blue color fringing on bright edges towards the borders and corners of the screen. Test patterns should make it easier to identify though.


Fixing convergence alone didn't clear up all the fuzziness around the borders of the screen, but it definitely helped the PQ in my case.
 

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I am wonder what the convergence tweaks you where able to do. Since I had my 34xbr800 ISFed I been really happy with the picture. The biggest issue I have with this set is that the corners are not as clear as the center.

Anyways I have the service manual and theres some good info on page 15 concerning adjusting the convergence. By looking at this it seems that to fixs the screen-corner misconvergence you need to open the TV and afflix a permalloy assembly to the tube itself to make the adjustments.

Since I am not at the point (yet) where I am willing to try that I thought I post here and see what others where able to do in service menu to inprove this issue. I did consider calling a service tech to do this but I have everything else adjusted just the way I like it and am afraid I get some tech that screw it up.
 

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I have a new Sony 32HS510 and I noticed a few areas of the screen with convergence problems. It's not terribly bad, and it's limited to areas of the screen that aren't really "in" the action, however to my discriminating eye, it is bothersome. From previous posts here, it sounds like it would be a considerably involved process to get this corrected. Is it considered a service issue? I mean, is "some" mis-convergence the norm? Would it be worth placing a service call and having the problem corrected?


Thanks!

- Mike
 

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It probably wouldn't hurt to inquire, Mike. I like to DIY, but that's not for everyone.


Ufanco,


I don't know if I did it the right way, or if I can explain my exact approach, but I didn't open my TV. All I used were the the D-Conv settings in the S.M. These improved the clarity IMO but didn't eliminate all the uniformity issues. The RGB guns may be better lined up, but there are still differences in focus, brightness, and clarity as you move from the center of the screen out to the edges. This is apparent mainly with a computer input and test patterns, but not so much with normal video viewing.


To improve the convergence, I basically worked from the center of the screen outwards. The upper right seemed to have the least play though, so I took that into special account when working the othe settings. After getting the center as perfect as I could, then a worked on the top, right side, and upper right corner of the screen until those all looked as good as possible, particularly the corner. Then I moved on to the bottom, left side and the other corners which were more easily adjustable on my TV... FWIW.
 

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ok going have to try that. Did you set all the D-Conv to 31( per service manual) before starting? Also what test pattern did you find the most usefull?


I misplaced my original settings and was wondering if you happened to write yours down before hand? Of course they might not even be the same as mine where but at least I can compare them to the ones on the excel sheet that are floating around on this BB. I did play around somemore and got it alot better than it was.
 

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I didn't start with them all at 31 (see, that's one of the benefits to owning a service manual :) ), but I did notice that all the values range from 0-63, with 31 supposedly being the median. FWIW, for 540p/1080i, the original values on my TV were:


YBWU 29

YBWL 30

RSAP 0

RUBW 62

RUMB 55

RLBW 21

RLMB 54

LSAP 21

LUBW 63

LUMB 34

LLBW 25

LLMB 39

CADJ 29

CPY2 0


I'm not sure what the last setting, CPY2 does.


The first pattern I used was a grid of white lines to give me a better idea what each setting did. To perform the actual adjustments though I just used a tiled array of 1 pixel white dots on a black background like a very orderly-looking star field. (Made in Photoshop and displayed via my computer input. However I think AVIA or VE may include somethin similar.) I tried to adjust the settings until the dots were as small and compact as possible with no red or blue fringing on the edges. Again, I'm not sure this is the recommend method. But it seemed to work in my case. Also if you intend to make any other geometry adjustments, you may want to do that before the convergence.


The order I used to adjust the upper right quadrant was roughly:


CADJ (center of the screen)


RSAP (right middle)

YBWU (upper middle)


RUMB (right upper middle)

RUBW (right upper corner, I assume)


And I followed pretty much the same pattern for the other quadrants of the screen. Perhaps the servoce manual recommends a different approach though.
 

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Ok thanks for the quick answer. This must be one of the things that are adjusted at the factory. Your pretweaked setting are different that the one I found another member had.


There is a comment concerning CPY2 setting in service manual:

After adjusting the following parameter, (D-Conv) write data into the NVM MUTING + ENTER then copy for 1080i CPY2

(D Conv item 13- Change data to 1 then write)
 

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Quote:
This must be one of the things that are adjusted at the factory. Your pretweaked setting are different that the one I found another member had.
Interesting. That would seem to make sense.


Thanks for the info on CPY2 too. Maybe that's some sort of shortcut for duplicating the new convergence settings from 480p to 1080i. Or perhaps it just creates a backup copy of all the settings. (??)
 

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Since the XBR910 seems to have add'l SM convergence controls, I'm not certain how well the approach for the XBR800, etc. would translate to it. The SM controls on the XBR800 are only for horizontal tweaking.


Also, I'm not necessarily sure whether it's best to adjust the middle of a quadrant (RUMB, RLMB, LUMB, LLMB) before it's corner (RUBW, RLBW, LUBW, LLBW), or vice versa. The implied order in the service menu seems to suggest that it's better to adjust the corner before the middle of the quadrant. However, as long as you know what area of the screen is being effected, it may not matter too much.


I'm pretty confident that it's best to adjust the center, sides, top and bottom of the screen first though, before addressing the controls for the middle and corner of each quadrant.
 

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ADU, Ufanco,


Interesting discussion. May I add some 910 comments?


Without any instructions from the service manual, I adjusted the 910 convergence controls in the order that they appeared in the service menu, and never touched CPY2. I didn't reset everything to 31 like Ufanco has mentioned. I just tweaked the original values from whatever they were at. Whatever I changed and saved (MUTING, ENTER) in 480i, automatically showed up in 480p/1080i. The 910 seems to have one convergence data base for all signal formats. CPY2 may not have any real functionality here.


The additional convergence SM items in the 910 are still for the horizontal tweaking only. The interesting thing is that my 910 shows almost perfect center-to-edge convergence using HDNet broadcast 1080i convergence pattern, which has a grid of fine white lines with center crosshair in each square box. The convergence is a little worst in 480i/480p modes using the DVE pattern. I don't know why. Thankfully, I don't watch 480i/480p on this set anyway.
 

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Thanks NTN1. So the 910 does have the CPY2 item, but you don't see much use for it? (I still need to try a few more things to understand this feature a little better.)


IAC, I haven't been able to get perfect convergence everywhere on the screen of the 34XBR800. Some areas require a little compromise. And there are a few areas (notably the upper left on my TV) which are misaligned vertically. But it looks alot better than it did out of the box (even though there was no box. :) )


I wouldn't be surprised if the 910 can be adjusted with greater precision though.
 
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