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I've been fiddling with Easy EDA a lot lately too, pivoting off of Frank's work. Getting better with it (I think). Working on this right now:


Just want my test bench to be uncluttered. The one I've used for so long has just been a stripped out harness from a cab. I put a 3P3T switch for all 3 voltages. A hole for calibrating the meter. A DPDT switch for onboard audio to output to an external speaker or to attenuate the signal for the onboard speaker. Test points for a probe. Extra +5v and +12v connections. Ability to use external controls. Most importantly, momentary switches for signal inputs.
I like this a lot. What connection are you using for video?
That's a great question.

I do and I don't. Not one of my PCBs, the end finished result, is autorouted.

If it's a small and simple design, I hand route.

If it's a complex design or I'm just feeling out the placement of components, I autoroute as a guide. A guide to see if the path of traces is optimal and also as a guide to determine the shortest path from point A to point B. With this information I remove the autorouting and hand route.

The autorouter is smart at routing the shortest possible path and keeping within design rules but is dumb when it comes to trace placement around vias or when to (and not to) jump between layers. It's also not always optimal regarding via usage (often using them unnecessarily).

I'd recommend autorouting and then verifying with your own eyes and brain. Delete, modify, move traces as you see logical.

Use the round track manual trace placement tool too. This provides you with autorouter logic but offers more control. It uses the same algorithm as the autorouter but allows you to create traces one by one.
Alrighty then. Auto-route, then manually fine tune it is. Almost done. Just need to beef up some traces and ensure the audio attenuation circuit is correct for the onboard speaker, then I can put in the order and test the sucker out.

Added JAMMA edge test points in this latest rev, moved the test points away from anything it could ground to, and made it a bit wider.

Are you going to provide a parts list as well? I'm really keen to see what you're using

I assume you're using the same tactile buttons as the Minigun but I'm definitely curious to know what speaker you're using, headers for external controls etc

The block of power connections on the side, is that power input or multiple test points? If multiple test points how do these work?
Right now, it is just a personal project with my wants and to suit my available tools and spare parts.

The block of power connectors is for powering auxiliary devices. Original intent was just to have a +5v connection for the Gonbes 8200 (GBS modded) to be powered for PCB repair. Then with some manual switching, I can pipe the video into a CRT for CRT repair and calibration. There is enough room on the board that I added extra taps for +5v and +12v to power what ever else might be needed: optical joysticks, analogue controls, small LCD screen. Designated test points are there to be used with clips for the probe.

The external controls use the 2x10 multi console pinout. I want to keep things compact, maybe even portable. So the idea is for me to use undamned USB controllers for external controls. Or wire up some of my cheaper fightsticks for test bench purposes. Honestly, momentary switches should take care of 90% of inputs in a test bench scenario. External controls is a luxury or for extended testing.

Will be using this speaker. I looked at other small speaker options out there, but mounting and size become difficult to solution. Not the best speaker in the world, but just need something for proof of audio working status in a test bench scenario. Fidelity isn't a consideration for the onboard speaker. Form factor and size is. There is a DPDT switch to output to an external speaker if needed.

Need a little help with attenuating the audio levels down for this speaker.
Thank you very much for verification!

Here are my files, feel free to use them for yourself :thumbup:

Please keep in mind that I'm not responsible for any harm this adapter does to you or your hardware. You can use my design at your own risk!
This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License.
And here is my redesigned version:
  • Replaced the solder pads with solder holes
    • Thereby allowing the signal lines to be accessible from either side
    • Eliminating the need for drill holes
  • Offset the jumpers and solder holes on the parts-side towards the empty key area
  • Removed one of the wiring stress relief holes from either side and moved the mount holes and remaining stress relief holes inwards
    • The more narrow profile should now allow the adapter to be bolted through to a cabs existing JAMMA harness so it doesn't come off easily
Gerber coming shortly........
Gerber attached. Use at your own peril :).


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Ha, I definitely had a deja vu looking at that last adaptor design there! ^^
Mounting screw holes is a nice addition for little projects!
any chance someone can make passthrough fingerboard similer to this one?
i need it for cps1.5


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The problem with making a so tiny passthrough is finding a PCB manufacturer that can bevel it at a reasonable price. JLCPCB and PCBWay require a way bigger PCB to do the beveling.
Frank posted a straight passthrough fingerboard in the first post on this thread. If you want it smaller, try taking a crack at it yourself. He posted the JSON file so you can do just that.
the issue isn't the passthrough
but the total width
and short pads on one edge...
not as nice as Frank's design
but it seems to fit