AES 3-5 RGB Cable Noise and Audio Hitch

doaal

Mr. Big's Thug
Joined
May 7, 2018
Posts
209
I've noticed an odd visual problem with my AES when using RGB. I'm using RGC's Genesis Model 1 SCART cables with breakaway audio for stereo (more info at https://www.retrogamingcables.co.uk...1-stereo-rgb-av-scart-cable-tv-lead-pro-build). They are well shielded cables with good build quality. But while they work perfect on my Genesis I get a sweeping noise pattern on my AES. It's a horizontal line that scans from bottom to top at some kind of slow frequency.

I wish I had a good way to capture it, but here's my best attempt. Notice the horizontal static at the bottom of the text window in the attached picture.

I also have an odd problem with my stereo jack. When the jack is plugged in all the way, certain notes in the lower register don't play. It's most notable during the bootup jingle where it sounds incomplete. Bass lines are missing from songs like the character select theme in AoF2. But when the jack is unplugged halfway, all the notes play properly.

I've cleaned all of the trouble areas with 99% iso, but that's about the extent of my knowledge. These are far from dealbreakers when using my AES, but if anyone can help me with either problem it'd be much appreciated.
 

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Neo Alec

Ned's Ninja Academy Dropout
20 Year Member
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11,925
I hope someone has a more definitive answer, because I just have some general concerns.

I'm guessing the cables use sync-on-composite, which could be causing the problem. If they don't, and use CSYNC instead, then there is too much resistance in the cable for the Neo Geo, because it's needed to attenuate the TTL sync from the Genesis.

As for the audio, I think there's something wrong with your headphone jack or cable. Does the Neo Geo work fine with headphones?
 

doaal

Mr. Big's Thug
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May 7, 2018
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In retrospect, I really should have tried another audio jack. Turns out it works fine with headphones! So while a Model 1 Genesis cable technically works, I guess its design is specced for that hardware, and I'll get a dedicated AES SCART cable to use. Thanks for the help.
 

Xian Xi

JammaNationX,
15 Year Member
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Dec 1, 2005
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Why would you use a Genesis 1 cable on a Neo geo? They're two different sizes of connector. One is a 262 and the other a 270. That's probably where your problems are. Use one made for the Neogeo.
 

doaal

Mr. Big's Thug
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At some point I was told the cables were interchangeable. And this does work well for the most part. Much better than composite and it'll suffice until I get the proper cable.
 

Xian Xi

JammaNationX,
15 Year Member
Joined
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Posts
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At some point I was told the cables were interchangeable. And this does work well for the most part. Much better than composite and it'll suffice until I get the proper cable.
You're going to end up damaging the AV socket on the AES, be warned.
 

maki

Edo Express Delivery Guy
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Jan 1, 2022
Posts
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At some point I was told the cables were interchangeable. And this does work well for the most part. Much better than composite and it'll suffice until I get the proper cable.
only the composite video cable with 5 pins is compatible
the full 8 Pin DIN connector has a different arrangement of the pins, you need to force it on and will probably damage the port

the Genesis/Mega Drive RGB cables are not really compatible!

Neo Geo will produce signals that are fit for monitor/CRT consumption

the Mega Drive/genesis RGB cable OTOH has extra components (R C) in it, these cause your problems

 

doaal

Mr. Big's Thug
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May 7, 2018
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In retrospect it makes sense they wouldn't output the same RGB.

Since that post I've gotten a proper AES cable and it works great.
 

maki

Edo Express Delivery Guy
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Jan 1, 2022
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hindsight is always 20/20 ;)

the power supplies of the Model 1 Mega Drive/Genesis and the 9V AES (POW3)are compatible, maybe thats why people mix that up

they both use the same RGB amp (CXA1145), but Sega decided to leave out components that are actually required and put them into the cable instead..
 
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