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Discussion Starter · #1 ·
one problem I saw when viewing the Cross Hatch pattern on AVIA was what appeared to be a "bulge" of the horizontal lines at the top of the tube. I have a feeling that this is a common distortion in CRT's, but there is a much smaller less noticible "bulge" on the lower most horizontal line. Is there an option in the service menu to adjust this distortion?? Also of note, I have a Polk CS400 center speaker above and now about 8-10 inches behind the front of the Screen (Not a perfect set up, but I'm working on a new shelf to bring the speaker flush). I am wondering if this distortion could be cause by a magnetic field from the speaker. The speaker is "shielded" but I am curious as to whether the speaker is shielded from the front, or just the sides, bottom/top, and back? Thanks
 

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It's possible some of the geometry service menu adjustments could fix this; I was able to find and fix several geometry problems that I picked up on with the cross hatch patterns on my set, but the geometry issues I found with mine were more of the minor pincushion variety (top third only). :p I guess it's also possible that a lack of proper shielding from the speaker could cause this, but AFAIK the magnetic fields from such things don't usually affect geometry too badly but rather really &^$# up the colors on the nearby part of the set. ;)


Perhaps a better description of what you mean by bulge would tell us better if the service menus can fix this or not (though my guess would be yes). :)
 

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Discussion Starter · #3 ·
Ok, let me try to explain it better. With the cross hatch pattern displayed, the uppermost horizontal line is parallel with the other horiontal lines about 1/3 of the way in on each side. In the middle though the upper most horizontal line in particular arcs up and then back down. It is most noticiable on the upper most line but it is present to lesser degrees on the second line down. On the bottom most line the same thing except it arcs down. It almost looks like a crystal ball is place in the middle of screen and just the upper and lower most portions are distorted. I don't know if that makes any sense, kind of a wierd analogy.
 

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Sounds like it should be fixable to me, though you'd almost certainly need to mess with multiple settings in the geometry section of the service menu to get it perfect. I say feel free to have at it after reading up on the service menu stuff first (on this forum and and other sites on the net). Before making any changes, you'll probably want to write down all current geometry settings so you can go back to what you've currently got now. This is important because you will (at least initially) have a tendency to pay too much attention to one area of the screen and get it perfect in that one spot and not realize that an adjustment you made actually made it quite a bit worse in another spot (i.e., worse than the original defect was :p). If you remember to write all original settings down, at least you'll be able to get back to what you originally had, even if you're committing settings as you're going.


You'll also almost certainly decide to spend some time in the dynamic convergence part of the service menus as well once you're satisfied with the geometry - I know that on my set, fixing geometry worsened my convergence in spots until I made adjustments with that as well, though I saw that convergence needed some work before I ever touched the geometry settings anyway. :) As an FYI (and maybe someone could help me here), I could not find anything to make any adjustments to vertical convergence at all; perhaps that can only be done with static convergence adjustment? (i.e., cracking open the set and making some physical adjustments, which is definitely beyond what I'm willing to do :p).
 

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Hello,


I have a 36XBR450 and it has the same problem. This is something that

Sony is aware of. Some sets seem to exhibit it more than others. I had

mine swapped out initially due to this. It was very noticeable when

watching a DVD in 16:9 mode. The set they swapped in its place had

it worse than the one it replaced. The service tech came out three times

to adjust it and he was able to adjust it so it's a bit better. The problem is,

in order to get it perfectly straight, the convergence would not be correct.

He spent a lot of time and came up with the best trade off he could.


He did mention putting a block of some sort under the yoke but I didn't

feel like having that sort of modification done to my XBR.


Regardless of the bow at the top of the picture, this is still the best

looking 4:3 picture I've ever seen. I have digital cable and the picture

is incredible considering it's plain old SD. Even a lousy VHS tape looks

good. DVD still looks phenomenal once you get used to the slight bowing

at the top of the screen.


Regards,


- Snappa
 

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Quote:
Originally posted by flynbw01
Ok, let me try to explain it better. With the cross hatch pattern displayed, the uppermost horizontal line is parallel with the other horiontal lines about 1/3 of the way in on each side. In the middle though the upper most horizontal line in particular arcs up and then back down. It is most noticiable on the upper most line but it is present to lesser degrees on the second line down. On the bottom most line the same thing except it arcs down. It almost looks like a crystal ball is place in the middle of screen and just the upper and lower most portions are distorted. I don't know if that makes any sense, kind of a wierd analogy.
There have been threads discussing this with the KV-34XBR800, too. You might want to check some of the discussions of geometry adjustment with that set. Here is a recent one:

http://www.avsforum.com/avs-vb/showt...hreadid=198611


I have one, but mine was pretty good geometrically as-delivered. I was able to improve it in the service menu a bit, though.


Phil
 
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