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Author Topic: Vga - Video Is Shifted And Too Bright  (Read 200 times)

AnnaOlum

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Vga - Video Is Shifted And Too Bright
« on: March 12, 2012, 11:03:00 AM »

Any help please?
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xboxmods2977

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Vga - Video Is Shifted And Too Bright
« Reply #1 on: March 13, 2012, 05:58:00 AM »

So you've stuck with the original LM1881 mod? IF so, try playing with the value of the resistor. Try some different value ones and see if that makes a difference.
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xboxmods2977

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Vga - Video Is Shifted And Too Bright
« Reply #2 on: March 13, 2012, 01:53:00 PM »

Ok, I read somewhere that your problem is another incompatibility with your monitor and your setup. While the H-sync and V-sync signals are almost "VESA perfect" using the buffer method, the Xbox RGB signals are a lower voltage than what standard VGA uses, which is why your picture appears faded. You will either need to build some sort of amplifier circuit for each of the RGB signals, or use a different monitor all together. I believe I remember reading somewhere that this can be fixed by building 3 simple transistor amplifier circuits. One for each color signal. I don't remember where I read it tho.
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ldotsfan

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Vga - Video Is Shifted And Too Bright
« Reply #3 on: March 13, 2012, 11:14:00 PM »

QUOTE(xboxmods2977 @ Mar 14 2012, 03:53 AM) View Post

I believe I remember reading somewhere that this can be fixed by building 3 simple transistor amplifier circuits. One for each color signal. I don't remember where I read it tho.

This article?
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xboxmods2977

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Vga - Video Is Shifted And Too Bright
« Reply #4 on: March 14, 2012, 06:34:00 AM »

QUOTE(ldotsfan @ Mar 14 2012, 06:14 AM) View Post
Nope, but that will work. Thanks L.
Anna, check out the diagrams that ldotsfan posted. There is an amplifier circuit there.

QUOTE(AnnaOlum @ Mar 14 2012, 12:05 AM) View Post

It's not really faded - it's like there's a white semi-transparent layer on the picture. The picture is too bright - not too dark!
The picture appears bright because in a television or monitor, you get dead white (brightness) combined with the RGB data colors (color). If the RGB data colors are not strong enough to match this white level, you get more white than color, causing the picture to appear bright.

QUOTE(AnnaOlum @ Mar 14 2012, 12:05 AM) View Post

BTW - the sync stripper method with the LM1881 did work but the picture was constantly jumping to the left a few inches and back again in higher resolutions. Would there be way to eliminate this?
Never had this issue. Not sure, but this could just be your monitor attempting to "auto-size" the image. Is this an issue with the HDTV? or CRT Monitor? or both?

QUOTE(AnnaOlum @ Mar 14 2012, 12:05 AM) View Post

Was your answer with the resistors related to this problem?
No. I was assuming you were having the brightness issue with the LM1881 method. It probably won't help the shift issue.
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xboxmods2977

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Vga - Video Is Shifted And Too Bright
« Reply #5 on: March 14, 2012, 07:50:00 AM »

It sounds to me as if your HDTV won't be happy, no matter what method you use. I would stick to using component cable for the TV and use your Xbox VGA with your PC monitors.
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