If you do have access to an optional NEC TG-16 A/V Booster, it will give you better picture detail over using the original R/F switch box provided with the TG-16 console. I've noticed better crisper video output image when using a Monster Cable RCA composite video cable.
Of course, the TG-16 and Turbo Duo consoles can output in S-VHS (or Super Video) and analog RGB (either European Scart or Japanese RGB output) provided they have been modded properly. Will require special Gamebit screwdriver (with interchangeable screwbit heads) to screw out the special screws that hold the consoles together.
PC Engine Fan X! ^_~