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fdasta0079

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So I recently redid the JAMMA connector on my Super Neo 29 after the old one started popping off, and I noticed that there seems to be some odd ghosting on the monitor now, with lines running down the side of the screen and lines coming off of UI elements. I've tried adjusting hold, RGB level, brightness, nothing seems to fix it. It's super apparent when running the NAOMI through the Capcom IO, but I also see it to a lesser extent when I'm running my Neo Geo board. Not really sure what's causing it (bad ground somewhere?). If anyone has any ideas, it would be much appreciated.



Lines within the "VS" sprite.



Lines to the left side of the screen and coming off the U in Ryu.



Lines to the right of the word Groove.



Lines coming off the right side of Ryu's sprite.



The generic JAMMA connector that might be causing the issues.



The spliced-up wire kraken. I had these wrapped nicely, but I took off the cable ties in case I was getting crosstalk. Didn't seem to do anything.
 
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PascalP

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You used a quality connector and did a decent solder job?
 

fdasta0079

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I used crimp connectors to splice the wires, and just cut from the old connector to splice to the new one. There is a good chance that the connector isn't great, since it's the same no-name harness that it seems like everyone on Amazon and eBay is selling.
 

fdasta0079

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Crud, didn't think of taking one. I'll grab one when I get home and upload it.
 

PascalP

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Ok, and you’re positive this ‘ghosting’ started after the connector swap?
Because if I would judge it without knowing the connector was swapped, I would say the monitor needs some work, e.g. Convergence rings or something
 

fdasta0079

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100%. It's super noticeable on the NAOMI boot screen.

I'm pretty sure it has something to do with the connector, since for a bit it was abated by moving the wires around. However, after removing the edge connector from the Capcom IO to test with the Neo Geo and putting it back on again, it seems to be stuck regardless of how the wires are jiggled. Could it be a bad sync connection?
 

fdasta0079

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I've updated the post with images of the connector and splices, and uploaded the photos to Imgur instead of hosting them on Google Drive. Thanks, guys.
 

PascalP

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well still I would say it is a monitor convergence issue, especially since it is more visible on the edge.
I bet the center of the screen is better? that's how it is in both my cabs, the center is razor sharp the the closer to the edge the convergence gets a bit off.
It's CRT, deal with it ;)

On the other hand, the Jamma connector is the 'standard' Chinese one which I've used on many adapters/fingerboards etc. without issues.
But your splices are just terrible to look at, please cut those piece of shit crimp connectors out of it and do a decent solder job with shrink wrap :)
 

fdasta0079

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Nah, it seems to have the same issues throughout the screen. It's definitely still noticeable on the "VS" in the center of the top screenshot. And it doesn't really look like the same color misalignment that seems to be characteristic of convergence issues.

I'll try rewiring the connector this weekend and see if that helps. Are crimps a bad idea to use?
 

Morzana

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The welds made by the Chinese on the jamma connector are always really bad
Also, 5V & GND wires section are too weak on these cheap harness

So take an soldering iron / shrink sleeve, and do the job by yourself ;)
 

PascalP

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Crimps are also a genuine issue for interference and bad contact, so take those out as well
 

fdasta0079

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The welds made by the Chinese on the jamma connector are always really bad
Also, 5V & GND wires section are too weak on these cheap harness

So take an soldering iron / shrink sleeve, and do the job by yourself ;)
I had noticed that the wire gauge was pitiful compared to the original harness. I might just have to get good at soldering up my own.
Crimps are also a genuine issue for interference and bad contact, so take those out as well
I'm going to try decrimping the video wires to see where that gets me, and then go from there. Probably ending with a complete overhaul of the connector.

Thanks for the advice!
 

twistedsymphony

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That ghosting you're getting is a classic analog video interference issue.

back before HDMI I would get that kind of effect on my projector when using shitty cables or shitty video switches.

You need to make sure the video ground on your JAMMA edge is not connected to the same ground as the power input. Make sure you're using good gauge wire for your video wires (22awg or larger). and make sure that the video wires are NOT run near the power wires.

Also get rid of all those shitty butt-connectors. They're straight trash and will cause more problems than they solve. You should avoid splicing wires whenever possible and use clean, un-cut wires between connectors with proper pin crimps at both ends. If that's not possible and you absolutely must splice wires then you should be using a "Linemans splice"
western-union-or-linemans-splice.jpg

I would be willing to bet that your noise is being caused by either
A. the crappy butt connector adding impedance on the video wires
B. the rats nest of wires you've got there leading to interference in your video wires
C. low quality/thin wires of that cheap JAMMA harness causing greater impedance and making the wires more susceptible to interference.
or D. a combination of all of the above.

Also make sure your earth grounds are all good, between your monitor and your cab and your AC block, and make sure that your video input wires are not run along side your AC input wires on your monitor (this can cause interference as well)
 

stj

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just buy a decent edge connector and a few meters of translucent heatshrink sleeving and do it right.
you dont want joints all over the place, and i dont trust crimp-style edge connectors.
those are probably the cause of all the burned atari boards from about 1977 till about 1984 when they just went to "universal mate-n-lok" connectors for the power.
 

fdasta0079

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UPDATE: So I bought a new Happ Super Jamma Harness, rewired everything, removed the Naomi power supply from the system, and I'm still seeing the same thing. Gonna check all my grounds and make sure everything is done up correctly.
 

streetfighterken

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Commenting to follow this. I have a Total Carnage with a soft image after swapping out the whole damn monitor and adding ferrite magnets to the video cable. Interested in secret and mysterious video problems.
 

fdasta0079

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Final update on this, ended up cutting some bad grounding out of the video wire that seemed to be the cause. Monitor looks crispy as hell now. Thanks for your help, guys!
 
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