Okay, I got a Neo Geo CD top loader in the mail the other day but it doesn't have the AC adapter. I have a pinout for it (10v 1A, GND, 5V 2A) and I made several adapters for it to try to get it to work. I used a 5V 2A ac adapter and then wired it to the console and used a seperate 9.5V 3A adapter (comes out as 10.2v) and connected it. The system starts up, I hear the opening chimes and the CD spins but no video?? It's a Japanese NTSC version so the composite out should work fine but I get no picture at all. (just some very dim strange black lines at the top of the screen). I then tried a 5v 3A adapter (LT1085), a 8.5v 3A adapter, and even a 12v 1A adapter....all with the same result.
Does anyone have this system and an AC adapter that they could tell me the EXACT voltage using a multimeter? The exact current draw would be really helpful too. but maybe there's something else wrong. I tried bypassing the protection didoes (in case they were the problem) but that didn't help anything either. I'm starting to think the problem is maybe the CXA1645p chroma encoder....any ideas?
Any help appreciated, thanks!
-Segasonicfan
NEO CD systems are incredibly fragile, they're dead as often as not, but it's usually the drive and AC adaptor that fails. It sounds like you've got the right idea, but it could just be that your system's somehow cacked it.
I don't have any AC adaptors anymore, but if you've got the specs and pinout then I can't imagine anyone measuring an AC with a multimeter will give you more accurate info.
ah, I WAS on the right track! I just pulled the RGB lines directly from the board (before they go through the CXA1645) and I got a great RGB picture =) So the problem is definitely that chip as I suspected since it has a voltage drop along all the outputs. I wonder how that blew?
No matter, I have a working Neo Geo CD =)
and Lawrence, I'm going to test the JP/US jumpers right away so I can verify that they work and add that import mod to GameSX =)
-Segasonicfan
Thats odd that the chip appears to be dead. Its not a very power finicky chip, and it sounds like you have a decent 5volts going to it. If your nuts you could transplant one from a dead genesis :)
yea i transplanted one from an old PSX....and it worked :D Sytem's running great now ^_^
-Segasonicfan