I just wire a straight 7486 here to combine the H, V sync to get composite
out, with a 75ohm matching resistor on the output whenever I hook up a
monitor. It has enough power to run the signal over the cable about 3ft. No
need for the extra components, RC delay in that schematic. Then depending if
you have pos. or neg. sync's you need a 2nd one to invert, as in that
schematic(4th 86) - that all what's done on a arcade board. I don't know
off hand if the Amiga has pos or neg syncs.
your welcome to have a few '86's , just let me know, I'll drop them in the
mail.
=Dan
--http://www.vintagecomputer.net/ragooman/