I recently finished building a supergun for my MV-1C Neo Geo. I built two video output connectors into it:
1. RGB-Scart directly connected to the JAMMA harness with 100 Ohm resistors on the 5V and sync line.
2. VGA using the cheap GBS-8220 converter, so I can use the MVS in my NAOMI cab.
I tested the RGB video on two TVs. On the first TV (Samsung plasma) the output is wavy, meaning lines are rolling diagonally over the screen. It's not very pronounced, but nevertheless noticeable. I assume it's because of the Neo Geos deviation from the standard 60 Hz frequency. Is this assumption correct?
On the second TV (Samsung LED) the picture doesn't have this problem, but whenever loud sounds are played there are lines rolling vertically over the screen. The louder the sound, the worse the problem. For the lines to disappear I have to crank down the amplifier on the MVS board nearly to zero. Is there any way to fix this problem without bypassing the internal amplifier?
Lastly the picture output by the GBS-8220 is jerky. Pixels seem to jump slightly on the screen. It's especially noticeable on the "Metal Slug X" logo on the attract screen and the names on the hi-score screen. Is this to be expected with the GBS-8220 converter or does mine have technical problems? From reading threads here most seem to be satisfied with the GBS, but I find this problem pretty annoying that's why I'm wondering.
1. RGB-Scart directly connected to the JAMMA harness with 100 Ohm resistors on the 5V and sync line.
2. VGA using the cheap GBS-8220 converter, so I can use the MVS in my NAOMI cab.
I tested the RGB video on two TVs. On the first TV (Samsung plasma) the output is wavy, meaning lines are rolling diagonally over the screen. It's not very pronounced, but nevertheless noticeable. I assume it's because of the Neo Geos deviation from the standard 60 Hz frequency. Is this assumption correct?
On the second TV (Samsung LED) the picture doesn't have this problem, but whenever loud sounds are played there are lines rolling vertically over the screen. The louder the sound, the worse the problem. For the lines to disappear I have to crank down the amplifier on the MVS board nearly to zero. Is there any way to fix this problem without bypassing the internal amplifier?
Lastly the picture output by the GBS-8220 is jerky. Pixels seem to jump slightly on the screen. It's especially noticeable on the "Metal Slug X" logo on the attract screen and the names on the hi-score screen. Is this to be expected with the GBS-8220 converter or does mine have technical problems? From reading threads here most seem to be satisfied with the GBS, but I find this problem pretty annoying that's why I'm wondering.
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