DarkOnus, thanks for sharing all this information. Also thanks for mentioning composite, I'm not sure how that option escaped me lol. Just pull it off the expansion port.
I was just checking the Ace's thread on sega-16 and it sounds like people are running into similar issues in the last few pages of the thread. They were discussing a couple of fixes. I have some pots I could replace the resistors with to fiddle around with. They were also trying putting caps inline with the rgb input resistors. not sure why. I think he originally designed it to work with genesis rgb so it may be worthwhile to compare the pc engine signal to the genesis one. I'll take a better look at my options once the boards get here and i can do some testing.
I also read through the SEGA-16 threads on ACE's mod, as well as those same issues and possible attempts to correct them. I had a couple pots to try myself, but for me the pots seem to be really finicky and difficult to adjust accurately and individually for each channel. Just popping in various resistors for each channel was easier and more accurate for me to try, though I did not have enough various resistors to attempt to test and try dialing in better combinations until a week ago when I received a large varying resistor kit . . . unfortunately I have not had adequate time to start testing the different resistors yet.
I did join the SEGA-16 forum last November too when I was first interested in trying ACE's design, and even though my account was registered, it was only ever partially activated, so even though I could login, send PM messages to other members, I could never post, change areas of my profile and some other things.
I would have been reluctant to post there and try to discuss the mod in detail anyway because there were only ever a few brief mentions of these mods being used with the TG-16 already in the thread discussing the BA7230LS mod, and since my only interest was in the TG-16, and it's not an NEC forum, I'm sure most their SEGA loyal membership wouldn't be highly receptive to any long discussion in getting the mod to work better with a TG-16 system anyway.
I did send a PM to ACE directly asking just a few questions about the mod, and his advice if it would be OK to discuss the mod on their forum concerning its use with a TG-16 system, but I never received a response, so I just let it go. That's why I joined this forum, in hopes that others here might have tried the mod already and could start discussing it more, or maybe some members would show interest in wanting to also try it after this new discussion was opened about it, or at least would want to join in on a discussion about it if they might be able to offer some suggestions. Sadly, that doesn't seem to be the case so far, except for KC offering some possible tips, and you actually buying a Helder board to try the design yourself poponon.
So I am really anxious for you to get the boards and start your testing, and I hope you will share all your results and ongoing experience with your testing of it here in this thread with me!
I'm also still wondering, have you thought about whether you are going to internally mod your console using the boards, or make an expansion port plug-in like I have done?
~ Craig ~
PS: Oh, and if anyone was interested at all what-so-ever in trying a different board than Helder's boards on OSH Park, I have quite a few extra boards of the ones I specifically designed using ACE's schematic, they are the same as the green PCB one I posted pictures of earlier in the thread. Anyone can PM me if they need more pictures and details of the board, and if interested in trying one.