The solution after a bit of investigation turned out to be quite simple, to bypass the Astec video modulator and apply a composite video ... attention to this Atari 800 laptop?

Composite video uses a single plug ... It's best known for being used on the Atari 800, the Commodore 64, and S-VHS players. You might also find S-Video on older DVD players.

[Ben Heck] posted this writeup about getting S-Video/composite out of an Atari 2600. This is actually the hack of [Longhorn Engineer], who showed it to [Ben] at a recent event. If any of you have ...