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Hi everyone. Finally getting into building this supergun thanks to this thread!

But, of course, I've run into my first problem. Does anyone have experience with a Mean Well RT-125A? It seems like no matter what I do, the green light just blinks when I power it on. I believe it's some kind of voltage protection mode? Either way, it's not sending electricity to anything properly. I'm located in the US, and the PSU is definitely set to 120v mode.

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The AC cord I'm using is a 10amp computer power supply cord. Do I need a 12amp or a different kind of cord?

Any advice on how to fix the green blinking light would be greatly appreciated. Thanks!
 
What @nem said. You need a bigger load on the power supply. Either a jamma board or some honking resistors.
 
Thanks for the replies!

I did try it with the supergun by itself, but I actually did not test it with a jamma board yet. I assumed the supergun by itself would draw power but I guess that's not how it works lol...

I'll try it with a jamma board and report back.

I already know it won't work properly, though. This was my first try at soldering and I screwed up bigtime on the microchip. I bridged the pins then ripped one of them off trying to desolder. But, hopefully I can still get some power flowing even if it won't work right.

Thanks again, much appreciated.
 
I already know it won't work properly, though. This was my first try at soldering and I screwed up bigtime on the microchip. I bridged the pins then ripped one of them off trying to desolder. But, hopefully I can still get some power flowing even if it won't work right.
When you say "the microchip" I assume you mean the THS7374 video amplifier. If that is left unpopulated, you obviously won't get any video output from the minigun. Though maybe you can see some LEDs light up and hear some audio out from your jamma board.
 
+1 for those answers. As the proud(?) owner of 3 x 125a’s I can confirm that they need to be powering something to actually work.

Expected behaviour with no load is flashing green light.

So you’re doing everything right, that power supply is working as expected. When you finish your supergun and connect it all up the magic pixies will flow
 
Thanks for the support, everyone. I am extremely pleased to report that it "works" lol

I'm just happy that it boots up and nothing exploded.

List of problems I noticed:
- Power LED on minigun doesn't work, but that's certainly my fault as I did not purchase the exact model from the parts list.
- Can't get any sound yet. It might work, I just haven't found out what the issue is. Nevermind sound works great! Just had to plug in the cord all the way...
- R pot works perfectly fine, but...
- G pot goes FULL GREEN when touched. Otherwise works and adjusts fine.
- B pot does absolutely nothing, which is why all my games display as blown-out blue.
- Yes, my arcade stick is currently a cardboard box... but anyway, when playing neogeo games the D and switch buttons on my controls do not work, and little test button on the minigun does not work.

I think that's it so far. If anyone has suggestions about these issues feel free to share. Maybe one power question I have is: Is it safe to leave the -5v connected to the power supply for a neogeo 4-slots? I disconnected it when testing because I was worried, but it would be easier if I could just leave it hooked up.

Thanks again everyone for confirming my wiring was good and telling me to just try a jamma board. I was too scared before.

From here I will order more parts and try making a 100% working minigun.

its-alive.JPG


When you say "the microchip" I assume you mean the THS7374 video amplifier. If that is left unpopulated, you obviously won't get any video output from the minigun. Though maybe you can see some LEDs light up and hear some audio out from your jamma board.
Ah, so that's what it does. Well then probably that pin I ripped off controls the color blue!
 
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Thanks for the support, everyone. I am extremely pleased to report that it "works" lol

I'm just happy that it boots up and nothing exploded.

List of problems I noticed:
- Power LED on minigun doesn't work, but that's certainly my fault as I did not purchase the exact model from the parts list.
- Can't get any sound yet. It might work, I just haven't found out what the issue is.
- R pot works perfectly fine, but...
- G pot goes FULL GREEN when touched. Otherwise works and adjusts fine.
- B pot does absolutely nothing, which is why all my games display as blown-out blue.
- Yes, my arcade stick is currently a cardboard box... but anyway, when playing neogeo games the D and switch buttons on my controls do not work, and little test button on the minigun does not work.

I think that's it so far. If anyone has suggestions about these issues feel free to share. Maybe one power question I have is: Is it safe to leave the -5v connected to the power supply for a neogeo 4-slots? I disconnected it when testing because I was worried, but it would be easier if I could just leave it hooked up.

Thanks again everyone for confirming my wiring was good and telling me to just try a jamma board. I was too scared before.

From here I will order more parts and try making a 100% working minigun.

Not trying to be mean. But that is an awful lot of issues. I suggest getting more practice with soldering before trying again.

The power LED on the minigun might be connected backwards. That is a common problem people have.
 
Actually, sound works perfectly. I just didn't have the 3.5mm cord plugged in all the way!

Not trying to be mean. But that is an awful lot of issues. I suggest getting more practice with soldering before trying again.

The power LED on the minigun might be connected backwards. That is a common problem people have.

I totally would practice more beforehand, but honestly I don't know how without just doing another supergun. Are there cheap practice boards and microchips I could get? This was my first time soldering, and by the end of this first supergun I already felt much more comfortable.
 
Actually, sound works perfectly. I just didn't have the 3.5mm cord plugged in all the way!



I totally would practice more beforehand, but honestly I don't know how without just doing another supergun. Are there cheap practice boards and microchips I could get? This was my first time soldering, and by the end of this first supergun I already felt much more comfortable.
Next time you are throwing away something electronic, disassemble it can take out the circuit board. You can practice removing and reattaching parts.
 
Next time you are throwing away something electronic, disassemble it can take out the circuit board. You can practice removing and reattaching parts.
I like that idea, thanks. I think I have some old stereo equipment I can dig out.
 
Stupid question.
Would HD Retrovision cables work from this minigun?
Thank you

Also can someone recommend a prefered power supply?
 
Stupid question.
Would HD Retrovision cables work from this minigun?
Thank you

Also can someone recommend a prefered power supply?
Any Genesis 2 RGB cable will work, if you have the 9 pin din version, hd retrovision included.
 
Hello everyone! I'm new to this forum, and had some questions regarding the Minigun Supergun. Now I ordered the Minigun V2.5, all the components, proper cables, built everything...the whole shebang. I have everything hooked up properly, getting proper voltages, but I'm having ONE problem...no video whatsoever. I get sound and controls while testing, so basically all is working, but no video. The only thing I can really think of at this point, is a bad converter board. I scrolled through each video output setting in the converter pcb menu, but no such luck. I'm using the 9 pin din to Y/Pr/Pb to the converter, then Y/Pr/Pb to VGA to the monitor. I've read that these converter boards are pretty much a crap shoot as far as functionality, so I'm hoping that's the issue. Anybody out there have any suggestions?? It would be greatly appreciated...as I am also still learning as I go, and am about ready to pull my hair out trying to troubleshoot the problem. Thank you for your time! :)
 

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you are using the component input on the gbs. I think you should use the CGA/EGA input on the left of the VGA input connector where you can feed RGB and sync.
 
you are using the component input on the gbs. I think you should use the CGA/EGA input on the left of the VGA input connector where you can feed RGB and sync.
Not quite sure how I would go about doing that? You'll have to forgive me..as I am still learning.
 
The converter pcb DID come with a wiring harness for the header pins directly in front of the VGA "in" input. Not sure how I would wire that into the 9 pin din connector though? Or would I be able to solder it directly to the jamma connector on the Minigun??
 

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This is a dumb question but for the 12V input does anyone have a link to a supply that works?
 
Quite sure the Minigun is only outputting RGBS, so no component without a transcoder @ph4ntomlord
The video out from the Minigun does indeed want to go to that wiring harness (the vga, rgbs pins and harmens are all the same input more or less…).
You can connect the Jamma boards directly to the GBs with some Jamma adapters:
eBay example
You will struggle to find a common cable to connect the two unfortunately.
Maybe someone knows of a US supplier of the above type breakout board…
 
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