I’d recommend getting a supergun. You can hook your JAMMA board to scart input without external devices as well, but you’ll then probably need pots on RGB lines and ~470ohm series resistor on 5V TTL sync line.
Thinking of consolizing an MVS, and have read about making sure not to damage the OSSC when hooking it up without a supergun.
In some topic I’ve read that you could also output the video to a din socket, and then use one of these Pakapunch cables (https://www.retrogamingcables.co.uk/sega/mega-drive-2/sega-mega-drive-2-sega-genesis-2-rgb-av-scart-cable-tv-lead) that have a built in 470 ohm resistor on the sync line.
When choosing this route, would the OSSC be safe?
I have also read about the amped audio output possibly being unsafe for OSSC. Is that true?