Neo geo problems

Hi everybody,

I explain the worry I have with a neo geo AES bought on the bay.

So I bought the console, the seller specified that it had sound but no picture and that it probably came from the scart cable.

Once the console was received, I had the blurred image and no sound. I cleaned the connectors of the console and the cartridge (art of fighting) and then I had the sound but still with the scrambled image (I saw the game start).

So I have clean again the console and the cartidge (with white vinegar), and since I have this image at the start of the console (and no sound):

WITH CARTRIDGE:




WITHOUT CARTRIDGE:




The picture is like scrambled but we can see when no cartridge is blue.

So I checked whether this could come from the transformer provided with the console, so I checked the voltage and it sends 15v instead of the 9 displayed



So I changed the transformer to see if the console was better with another and I tested with a 9v 1A, but I have the same result as with the other.

Would you care where the worry comes from? Here is a picture of the motherboard:



Thank you in advance !

Have you tried hooking it up to a different TV (preferably a CRT) ?

You seriously cleaned the cartridge slot and a cartridge with white vinegar? You only use that for battery/capacitor damage, not for general cleaning.

If it's not the TV, it looks like the console has a bad sync signal.

Clean it again with an alcohol/water solution or use the eraser trick. Once the qtips come back spotless, then see if you are still having issues.

Also, not sure what that wire is doing there.

just desolder the yellow cable. I tested on another TV. I tried with another cable scart bought on ebay http://www.ebay.fr/itm/361027198062 I have the same problem but in black and white.

Would you have another idea?

sync signal issue probably , this AES is a EURO RGB modded, distributed by Guillemot in France , the mod wire was done for the TV commutation.

The scart cable is probably carrying the C-sync on pin 20 instead of composite video. Most French TV will only sync on composite video.
Make sure pin 20 connects to pin 3 of DIN8 connector

Vendest said:

The scart cable is probably carrying the C-sync on pin 20 instead of composite video. Most French TV will only sync on composite video.
Make sure pin 20 connects to pin 3 of DIN8 connector

Click to expand...

I have checked with a multimeter and pin connectors to pin 3 of DIN8 connector

In between I made this modification and tested on another TV :




With cartridge



Without cartridge:



I still do not have the display that works

The sync issue seems solved , but you have another one , and more serious this time .... certainly not due to the scart cable .

This type of screen with garbled character usually indicates issues with the bios. Any bad traces from/to the bios?

Do you think it is possible that by changing the bios for a Universe bios, would this solve the problem?

It could, if anything it'll help narrow down the problem. Might be looking at bad traces or RAM.