nmalinoski – isn’t game PCB sync output typically TTL? So, it really would be a simple direct connection for RGBS to a HD-15 the appropriate pins on AV3 (csync on pin13)?
I don’t really have experience with arcade hardware, but if it’s TTL RGBS like an SNES, then yeah; you could slice off the end of any old VGA cable, attach R, G, B, and S to the screw terminals (Good luck making a connection with ground/shield, though), and AV3 should take it.
The possible concern is if it’s not very-high-quality RGB output, like a lot of old home consoles. If that’s the case, it would be better to use a cable with components, or something like a supergun, to take advantage of the better low-pass filtering on AV1.
(Good luck making a connection with ground/shield, though)
You mean the shield on the cut VGA cable? Yeah, how exactly is the best way to bond to that? I’ve seen in my scart cables that they basically just pinch the shield against a ground point or ground wire, so it’s making constant contact, but it’s by no means mechanically attached.