The standard 8-pin DIN that you buy at any electronics shop has the pins too close together for the mega drive 1. They have to be severly bent and forced into the unit. Any thoughts? Does sega have a specialised 8-pin connection?
It's actually the U shaped 8-pin DIN that's found on the Genesis, whereas the roundish one is found on the Neo Geo amongst others. Both are standard plugs, as is the mini DIN plug used on the Genesis 2 etc. - the only Sega consoles to use proprietary A/V plugs are the Saturn and Dreamcast.
The 8-pin U-shaped ("offset") plug, suitable for the Genesis/MD 1, can be bought from http://www.maplin.co.uk - the order code is FG40T.
You only need the 8-pin plug if you're wiring up a RGB cable - if you're doing a standard composite A/V cable, a 5-pin or 3-pin DIN will do.