JAMMA extension - How to connect it properly.

Daeds

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Hello there!
As a green onion with all these connections, boards and adapters I've came to a big and dangerous doubt now that my JAMMA extension arrived,
It has no indicators on which way I should connect it and I'm scared to death of frying something. o_O
Here it is in all it's glory:

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I see it has a notch on the board that connects to the Supergun and I know the way it should connect on the board (the black connector), I just need to be sure o which way to connect the board thingy to the Supergun.

Can you help this newbie out?
Thanks!
 
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The power cords start at pin 1.
That extension is of low quality. :(
The power pins should be bridged on both sides, or better, each pin has it's own cable.
Same at the other side (pins 27&28).
 
That won't fry your stuff, but depending on the current the board drains, the connectors can get warm.
 
That won't fry your stuff, but depending on the current the board drains, the connectors can get warm.
Maybe I should solder a thicker wire, at least in grounds and power, right? It's 20awg, seems too thin.
Direction wise, what is the correct way to connect the board thing into my Supergun connector?
 
You power wire in jamma should always be 18ga or thicker to allow for better flow of the 5V and 12V DC power. The cheap china stuff just uses thicker insulation and is not as effective in allowing enough current to flow for some boards. Your red (5V) yellow(12V) and black (GND) wires help you with orientation of the jamme edge connectors. Once I have the correct orientation of the edge connectors I mark them with parts side (top of the board) and solder side so I know which way it goes for future reference.
 
Look at a JAMMA pinout. The black, red and yellow wires are your power and grounds (black ground, red 5V, yellow 12V). That lines up with the board accordingly and then you trace the wire back and orient it the same way at the other end.
 
You power wire in jamma should always be 18ga or thicker to allow for better flow of the 5V and 12V DC power. The cheap china stuff just uses thicker insulation and is not as effective in allowing enough current to flow for some boards. Your red (5V) yellow(12V) and black (GND) wires help you with orientation of the jamme edge connectors. Once I have the correct orientation of the edge connectors I mark them with parts side (top of the board) and solder side so I know which way it goes for future reference.
Yeah, I suspected it, I never use thin wire for power in any other electronic stuff, will have to change those up at least.
Look at a JAMMA pinout. The black, red and yellow wires are your power and grounds (black ground, red 5V, yellow 12V). That lines up with the board accordingly and then you trace the wire back and orient it the same way at the other end.
Thank you!
 
You should throw that thing in the trash and make a decent extension.
More and more I guess this is what I should do... It was a cheap buy from China and I guess I shouldn't use it,
I could use the connector and the board for some decent cabling, right?
Thanks!
 
More and more I guess this is what I should do... It was a cheap buy from China and I guess I shouldn't use it,
I could use the connector and the board for some decent cabling, right?
Thanks!
Run all 4 +5V and GND connections back to the fingerboard and it'll at least be usable.
 

You can see from this pic on Twisted quarter website they populated all the power pins including the -5V.

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@RiddledTV makes some good quality jamma extensions.
Sadly it's far across the globe for me. :(
Run all 4 +5V and GND connections back to the fingerboard and it'll at least be usable.
It's not that I need it, it would make my life a bit easier since I'm playing through the supergun and would be easier to disconnect and connect the boards. :D

You can see from this pic on Twisted quarter website they populated all the power pins including the -5V.

View attachment 843858
What a difference, just saw mine misses lots of pins, what a bummer. Well that's what I get for the price I guess.
 
It's a good learning lesson. Do you have the ability to solder? If so, this might make for a excellent small project to practice on. Like Mike said above just add the missing power wires and that should be ok for now.
 
It's a good learning lesson. Do you have the ability to solder? If so, this might make for a excellent small project to practice on. Like Mike said above just add the missing power wires and that should be ok for now.
Yup, I do love soldering and I'm learning electronics, one of the things that brought me to collecting the PCBs is that part actually. :)
 
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