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jiml

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  1. Sorry for double posting, but i can't edit my posts for some reason...Maybe cause of low post counter? What i mean is that static vertical lines shown in the picture above, suggest something like an rc filter effect on the line with the same phase of the singal, clearly distinct from white noise. Whereas diagonal moving lines suggest white noise or some kind of interference, that can't be phase locked and thus is moving. Grounding or/and better wiring should only help the later case.
  2. Oh, that's interesting. A lot of people say that changing spots to solder helped with the "wavy line" effect , but didn't get rid of if totally. Were the lines you were getting static vertical, or were diagonal moving? Are you sure this picture from the dashboard is 480p and not 720p? Could you try with a game that goes only up to 480p?
  3. Ok, to the people getting this kind of "wavy lines". I've had the same effect with the VGA mod at 480p games. With games running at 720p there are no "wavy lines" and the image is crisp. I tried the console on 4 different lcd monitors/tv and on all of them i had the same effect. This effect can be solved by adjusting the coarse/fine or clock/phase of the monitor, but then the picture gets stretched so much that some of the picture goes off the limits of the screen. This problem only occurs on new lcd displays. I've tested the console on an old crt display and there are no "wavy lines" at all. I'm not 100% sure but, after doing some search i found that xbox outputs EDTV 480p signal standard that translates to 852x480* resolution and not VGA standard 640x480. The monitors recognize the incoming image resolution from the hsync clock frequency. So EDTV 480p and VGA 640x480 have similar horizontal sync clock frequency ~31,7kHz but different pixel clocks([email protected] vs [email protected],125Mhz). That's why, when i set the clock on the image settings of the monitors at 852 exactly, i get no "wavy lines", but the image gets stretched. Those "wavy lines", to my understanding, have nothing to do with noise interference. Thus better shielding/grounding/changing caps etc. won't help at all. What does make the effect worse is the sync clock signals skew or poor rising/ falling clock edges that the encoder chip on the xbox produces at 480p. Might be, that the old crt's aren't effected a lot by this, but the new lcd monitors are more susceptible to this poor signal. This effect gets worse because of the digital upscaling the digital lcd circuitry applies. This has been also tested: On my old 32" Samsung tv monitor, when i connect the xbox via the component input, there are no "wavy lines" at 480p HDTV games. The same xbox set to produce the same component HDTV output as before, but connected to the vga input of my tv monitor produces those "wavy lines". What i can understand from this is that because the monitor uses different circuitry to decode component and vga signals, either can only apply the EDTV 480p standard on component inputs or the circuitry that decodes vga/hdmi is susceptible to clock skew or poor sync signals.

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