Jamma Extension Hardness/Loom Problem

Arcade cabinet hardware and accessories
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gamescollector
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Jamma Extension Hardness/Loom Problem

Post by gamescollector »

Hello Guys
I recently purchased 4 extensions jamma.
http://www.ebay.com/itm/ARCADE-MACHINE- ... 41900b2d20"
I have a big problem when I use them. Let me explain, if I plug a standard jamma everything works perfectly. But if I connect a CPS2 A + B game gives me a full black screen.
I have tested on four different cabins

please help me

Ivan
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ikaruga007
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Re: Jamma Extension Hardness/Loom Problem

Post by ikaruga007 »

Bought one of those a few years ago, just when I bought my first cab. They're total crap I'm afraid, mine came with at least one completely loose solder joint and IIRC it uses too few wires for ground which is alway a sign of a cheap loom. I've since butchered it when I've needed some wires. Hope you get it sorted, but I'd look into getting some higher quality looms.
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crunchywasp
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Re: Jamma Extension Hardness/Loom Problem

Post by crunchywasp »

Those cheap extensions or JAMMA harnesses on eBay tend to have an inadequate quantity of copper on the +5v lines too (usually there are only one or two thin gauge wire(s) soldered to all 4 pins :problem: ) so there's probably a big drop between your cab and the board which would explain the black screen. If you check the voltage at the JAMMA edge with and without the extension I'll bet there's a significant difference. Adding some thicker gauge wire to all 4 +5v pins and the missing grounds is likely to remedy the problem.
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Re: Jamma Extension Hardness/Loom Problem

Post by gamescollector »

Thanks I try tonight, hope to solve the problem.
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Re: Jamma Extension Hardness/Loom Problem

Post by KmanSweden »

Wtf?!
The edge in the pic is missing almost half of the connections?
Up the Irons!
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