Thank you all so far

The impression I now have is that i should forget about the composite video output, and instead try to convert an existing monitor for use with the Classics logic board. This does not only require a special monitor, or some experience of fiddeling with an existing one, something that I'm not quite capable of doing

Sadly, this is not really what I had in mind...

Is there really no circuit known to man, that could convert the video out to a standard VGA signal? I will forget about composite video, but please help me get VGA