Turbo Grafx 16 A/V out mod? (RCA/composite)

[kspiff]

I'm trying to modify my Turbo Grafx-16 to allow for RCA composite output. I'm not having much luck as yet. I tapped the composite video line and ground (using the expansion connector pinout from gamesx.com), but I can't get a picture when I hook up to my TV.

Has anybody ever seen (or performed) such a modification? At this point I'm wondering if I need to use a video amp like when I did the NES2 A/V mod (again from gamesx.com). That mod also required removing a resistor and cutting a trace, though, so there may be even more to it.

And yes, I know I can just get a CD add-on or Turbo Booster Plus but I don't really care to have either and am trying to do this on the cheap. Actually, though, if anyone happens to have a Turbo Booster Plus schematic or unit they could open and snap a pic of it might help (it's asking a lot, I know).

And before anyone asks I did try to post this question at gamesx.com but something appears to be screwed up w/ their forums.

[kspiff]

A follow-up: anybody know if I'd be running the risk of frying my console if I tried tying composite sync + video together? I tried messing with this again and the sync pin pulses the screen while video does nothing.

*sigh* I should just stick to mods that don't require any thought. Oh, well, back at it then. :deadhorse:

EDIT: Damn. I think I answered my own question by doing some more searching. Looks like the term composite video generally refers to a signal w/ sync. Oh, well.

[FABombjoy]

The composite pin on the big connector can be used as-is, so if you have no picture then there's something wrong with your wiring, connector, or the TG16 itself. At one time I used a homemade A/V cable that connected directly to the video & R/L audio pins.

[kspiff]

Hm. Then I'll try wiring a cable directly to the connector just to see if it works. I'm using a 9-conductor ribbon cable on the inside and I guess the wire may be too thin.


The composite pin on the big connector can be used as-is, so if you have no picture then there's something wrong with your wiring, connector, or the TG16 itself. At one time I used a homemade A/V cable that connected directly to the video & R/L audio pins.

[kspiff]

Ah. You were right. I was using a pic from gamesx.com to orient myself w/ the pinout and when I went back and looked at it (for the 50th time) I noticed the pic was of the female expansion port on the CD add-on (it even had a note had I bothered to do more than skim the article).

Man, this thing looks way crisper w/ composite. Too bad the TV in my living room doesn't support s-video (not that I'd want to be bothered with procuring the chip needed to make the stand-alone convertor D-Lite uses).

[77punk]

hey can you take pictures of the composite tG16 i want to do it now.. The RF on there FAIL!

Thanks