Homemade composite to VGA converter

Anyone has a way to do a homemade electric diagram of an RGB to VGA adaptor that would work on a MVS motherboard (MV1A to be precise)
I did one already but I have problems with the Vsync that doesn't seem to work...
I could just buy one, but I'd really like to build one myself

Flavien

Corrected

http://elm-chan.org/works/sc/report.html
http://www.analog.com/en/analog-to-digital-converters/video-decoders/ADV7181B/products/product.html

Are you sure you did one already?

Err, if you'd done one already, you'd at least know that the MVS outputs RGB, not composite.

Hewitson said:

Err, if you'd done one already, you'd at least know that the MVS outputs RGB, not composite.

Click to expand...

lol
yes sorry about that... Im doing the composite output right now lol. Nixed up things
Ill check the first 2 links a bit later, Ill keep you in touch with that

Thank you