Neogeo aes with rgb cable - image jumps around

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Purgatorius

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Hello, I have some video problem with neogeo aes and and I'm looking for help.

Just got my first neogeo, it came with a modded megadrive pal rgb cable ( sync on pin 7). When I hook the console to the tv, image jumps around and is unstable, resolution seems to change every half second. Is there a way to fix this ?

Here is my setup:
-neogeo aes first revision motherboard
-megadrive rgb cable with sync on pin 7
-sony wega crt tv (100hz)

Thanks
 
Atro

Atro

Who?,
20 Year Member
Joined
Jan 30, 2002
Posts
9,213
Hi.

First things first. The MD RGB cable if french, has an amplified signal as it uses transistors inside.
The 100Hz TV is crap for 15Khz gaming. Specially WEGA's. Try on different tube first. If you say it's on pin7, it's raw sync from the system.
However, the MD RGB cable also has that signal amplified and can also be (part of) the cause.
 
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Purgatorius

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Yes it's a french megadrive cable, with a box and transistors inside. I also have a pc engine modded with the same kind of cable and it's working without any problems on the same tv.

I tried the console on a toshiba crt (100hz also, i dont have access to older crt for the moment), image is stable this time but it gets distorted as you go from bottom of the screen to the top.
 
Atro

Atro

Who?,
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It works fine with the PC Engine because the PC Engine *needs* the amplifier in order to get a bright picture. For that purpose, that official MD cable is perfect ( I also use one for my Super Grafx ).

If you can't access a different CRT, try using on a newer TV set with scart RGB. As long as it has RGB you should be good. You just won't have scanlines.

If you plan to use that cable, then do straight connections for the RGB and Sync lines.
 
Xian Xi

Xian Xi

JammaNationX,
15 Year Member
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Posts
27,750
If it's a 1st gen AES, you need to swap out the 100uf caps for 470uf ones, it's a coupling issue.
 
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Purgatorius

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Xian Xi said:
If it's a 1st gen AES, you need to swap out the 100uf caps for 470uf ones, it's a coupling issue.
Click to expand...

Ok I did a full recap of the console with a kit from console5, replaced the 5 100uf caps with 470uf caps and the resistors that comes with the caps also.
Picture is great, but I still have issues with the image going crazy on my TV.

I read somewhere on the internet that the frequency on neogeo is different from other consoles, it's not really 60hz. Could this be the issue ?
 
Xian Xi

Xian Xi

JammaNationX,
15 Year Member
Joined
Dec 1, 2005
Posts
27,750
Purgatorius said:
Ok I did a full recap of the console with a kit from console5, replaced the 5 100uf caps with 470uf caps and the resistors that comes with the caps also.
Picture is great, but I still have issues with the image going crazy on my TV.

I read somewhere on the internet that the frequency on neogeo is different from other consoles, it's not really 60hz. Could this be the issue ?
Click to expand...

yes but don't you have RGB?
 
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