thanks, i could manage to knock one up, except for the fact i don't have any d-subs that aren't already functional (regular) RGB cables. (or 9-pin Serial cables for that matter)
S-video is luma/ground chroma/ground which is compatible with the regular 8pin DIN (40col) connection (which has luma/chroma), but not the RGBi, you'd have to buy a converter...i was able to knock together a commodore 40col -> SVideo adapter just with dollar-store SVideo+RCA extension cables. (though i didn't notice any real improvement in quality)