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Happy
Grand Master
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Hello,

I have come to the point today that either using the most common jamma extenders or putting the supergun or the jammafier directly to the pcb both solutions are so fragile when it comes to change often PCBS.

- Jamma cable : loss of voltage, loose pins, solder going bad
- Straight to the connecter : plastic enclosure can break when trying to put out the pcb with left/right movement, pcb solder can break also when it's not perfectly aligned

Today I came to the conclusion I need a strong quality built jamma extender cased on both sides with the right cable gauge, and good quality pins.

Is there such a product available ?

Thanks

UPDATE 20181221 : Here are the parts to order :



IDC Connectors


IDC Sockets


Ribbon Cable


24 Pin Female Socket


30CM ATX Cable
 
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I'd be interested in getting a quality JAMMA extension too - all the ones I've seen for sale have been garbage.
 
After reading some discussions on other threads I found that some good basics on electricity would be welcome before making such cables, (gauge, length, interferences, ground straps or not...)

I guess some people here can share good information on how to build a proper jamma extender cable that doesn't affect the pcb.

@twistedsymphony it would be a nice project to make printed casing for jamma end

found this casing at least for one side

https://www.arcadeworlduk.com/products/JAMMA-Harness-Cover.html

Jamma_Harness_Cover_1__97831.1434019635.jpg
 
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I've been toying around with an idea...

How about producing them from flexible PCBs? Utilise a rigid PCB for each end, one as the male finger and the other as the jamma edge connector, and interconnect with a flexible PCB ribbon.

I've been meaning to get something designed and mocked up, just haven't gotten around to it.
 
Is there any alternative to protect the jamma end on the male side ?
What shape is the PCB? you can't design a protective cover unless you know the shape of the PCB and have some holes or something that you can secure the cover to.

I'd suspect something like that doesn't exist because no two finger-boards are similar enough to make a product that works for everything.
 
I've been toying around with an idea...

How about producing them from flexible PCBs? Utilise a rigid PCB for each end, one as the male finger and the other as the jamma edge connector, and interconnect with a flexible PCB ribbon.

I've been meaning to get something designed and mocked up, just haven't gotten around to it.
Sounds like a great idea. However it seems like we need some electrical knowledge on what are Jamma standards. I have read that some requirements are needed like AWG 18 for common cables and maybe more like AWG 20 for +5V -5V and ground. There are tons of conflicting discussions about what is really required to avoid a lot of problems I wasn't aware of, like how different grounds are used in different pcbs, electromagnetic noise, audio insulation, voltage
drops...

I also find this informative :

http://www.therealbobroberts.net/jh.html

Is there any alternative to protect the jamma end on the male side ?
What shape is the PCB? you can't design a protective cover unless you know the shape of the PCB and have some holes or something that you can secure the cover to.
I'd suspect something like that doesn't exist because no two finger-boards are similar enough to make a product that works for everything.
Good point. I haven't compared the fingerboards available, I was assuming they were all the same size.
 
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This is something I would most definitely be interested in going in on as group buy if multiples needed to be ordered. Hopefully someone will step up to the plate that can make them. Ebay Jamma extenders are terrible in quality and I myself would at the very least need three of them made just for myself.
 
Simply put I only consider extending JAMMA for testing. I never recommend extending a JAMMA harness in practice or production unless necessary. Thin wires cause resistance / voltage drop, but even with thick or proper gauge wire you lose some amount of voltage with every foot of wire. Overly thick wires have their own issues too.

What is most peoples use for these? If just for supergun use, making a product run might be feasible with enough interest.
 
Thin wires cause resistance / voltage drop, but even with thick or proper gauge wire you lose some amount of voltage with every foot of wire
Technically true but not a huge issue for the lengths most people need:
ResistanceChart 001.jpg
 
I know that in paper. In practice... You lose volts most of the time. I know generally 5ft or less is negligible for analog, but we are talking a huge mess of unshielded wires.
 
I know that in paper. In practice... You lose volts most of the time. I know generally 5ft or less is negligible for analog, but we are talking a huge mess of unshielded wires.
I think voltage drop will be slight but nothing adjusting your PSU up a little can't accommodate.

the bigger issue is, as you said, the unshielded wires, interference on the video out and audio buzzing will probably be the first symptoms.
 
I find video interference to be affected as much or more by PSU age than shielding but both help.

Adjusting the PSU is fine of course within reason.
 
What is most peoples use for these? If just for supergun use, making a product run might be feasible with enough interest.
I need one because the stupid flash drive sticking out of the front of the Griffin Aerotech hardware makes it so I have to disassemble my HAS SuperGun to make it fit! :D

IMG_4960 (1).jpg
 
My System C2 was so tight inside the HAS that it couldn't get out without some left/right movement which broke a piece of plastic. I was able to glue this piece of plastic again but it's definitely broken.

This is something I don't want to happen again. I also use a jammafier and I want it to stay secure from accidents.

Shit can also happen on the jamma side when feet are not aligned.

I think this thing can happen accidentally even with good care.

Having a good quality short extender could save from breaking some things.
 
As nice as they look, and I love the design, doesn't it defeat the purpose by being on a large PCB? May as well just connect a supergun directly. Also the power wires look inadequate.
 
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