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Discussion Starter #1
Working from Video Essentials... all references to test patterns are from it. Set is a KV-35S42


1) Even with Sharpness all the way down, the black part of the needle pulse is bent. Is there anything that can be done? Or is that an issue with power?


2) When adjusting VSIZ and VPOS with Overscan pattern, the right side of the pattern "wraps around" itself short of the edge of the screen. So, if I move it far enough left to not be wrapped around itself, there's a half-inch of black down the right side of the screen.


3) ROTC (Rotation Coil) rotates the whole image (again with the Overscan pattern). But the error is more of a vertical trapezoid... top and bottom horizontal lines are skewed, but left and right vertical are OK. Start to rotate to correct top and bottom, and the sides get out of whack. Any way to compensate for that?


4) I cannot find an adjustment for SVM. There are three video "modes" in the user menu... "Vivid" (read: torch mode), "Movie", and "Standard". I'm on Standard, but I know what seems reasonable, isn't necessarily. Anyone know if Movie might be more accurate?
 

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I *think* the answer to #4 is to use Movie mode--I think that defeats SVM on Sony TVs.
 

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I have the same problem on my Sony KV-36XBR250-- an outward bowing throughout the lower half of the needles. I don't think it's a power problem, though. My understanding is that geometry problems from overtaxing the power supply tend to cause insufficient voltage to be applied to the deflectors, which I would think would cause an inward bowing. See the demonstration on the Video Essentials DVD for an example of this. At high white level settings (don't do this) I was able to see a VERY slight inward bowing on the top inch or so of the black needles.


The other reason I don't think it's a power problem is because I see the same effect on circles and crosshatch test patterns, even at very low levels (like 40 IRE or so crosshatch on black)-- about the same amount of bowing (less obvious because it's not JUST the vertical bars), and also only on the bottom 1/3 to 1/2 of the screen. Since the gun's hardly firing on those, there should be loads of power to spare.


That said, I don't know what would be causing these problems. I was starting to wonder if there was defective shielding on my center speaker (which is under the TV), but there's no color distortion.


I guess I'm saying that there may be something we mortals can do without redesigning the power supply, but it would probably require a professional calibration, and I still can't be sure even then.
 

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Hi:

The needle pulse pattern is used to check the power supply and not sharpness. First check your geometry using a crosshatch grid look for any vert. bent lines. If they are fine then go to the needle pattern. Slowly turn down the contrast or picture setting and the needle should start to straighten out. You stop when the line is straight or when it starts to bend more. Sony has figured a way around this pattern so I think that you more than likely have a geometry problem. You turn of SVM in the user setup/ preferences menu. You use the sharpness pattern to adjust sharpness. Look at the plus sign in the middle of the screen, ignore the overscan lines they are wrong on this pattern. If you see a ghosting effect just to one side of the plus sign start backing off on the sharpness until it goes away. Do this after you have turned off SVM as it can be confused for sharpness artifacts. Use the movie setting. Also the bending that you see at the extreme ends of the crosshatch grid is due to the retrace rate of the yoke. It is not fast enough for HDTV 1080i

Hope this helps.
 
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