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Any good quality bipolar cap should be fine - I would probably use Cornell Dublier just because I have them on hand for Midway sound boards but Nichicon is an excellent brand and should be a perfect replacement
 
I have them a plenty. 2 built and about 8 boards left. All Because I needed one for my test bench.

Price is negotiable I had them listed in the sales forum at $80usd but the Aussie dollar has crashed since that post so $75 is more like it now and that was just an estimate of the parts cost plus my time. I don't do this to make money. Any proceeds will go into building the TD-IO (which I have a few PCBs spare as well if anyone else is interested in building one) Not yet offering the TD-IO as a built unit untill i have worked out the wrinkles. $5 donation to @Frank_fjs on the minigun is included in any sales likewise (but only $2.50 as its just a blank PCB) for the TD-IO.

Mine are the 8Pin Mini DIN if you are looking for the 9Pin @xodaraP is you man.
 

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I'm happy to report I managed to build one as well!
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It was great fun, but it's actually my second attempt at it, the first attempt a couple of months ago was one of the first things I seriously attempted to solder and it didn't have a happy ending, although mostly due to a very silly thing. I had everything put together except for the JAMMA connector which I thought would be easy, but while soldering I didn't pay attention to the alignment with the board at all, so it ended up at an angle, which I disliked heavily... so I thought I'd try to desolder it and try again. That was a mistake:
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... I did eventually get better at it and desoldered rest of the components to use on a fresh board (and also bought a cheap desoldering pump with integrated heating, which made this 100x easier :P), but not without breaking legs off some components at first - thankfully, there were not many casualties so I was able to reuse almost all of it for the second attempt.

Differences from the digikey BOM of the final attempt:
- I replaced the 100uF capacitor (I broke the leg off the original) with a similar Nichicon but with lower temperature rating I got from Aliexpress - this is the sketchiest difference, since I ordered a batch of 10, but I tested them in a tester and half of them were closer to 50uF - I picked one that tested good but I'm definitely replacing it next time I'm ordering something bigger from Digikey
- mini DIN socket is also from Aliexpress, I broke a leg off the original - this one seems fine, just a bit lower quality
- SMD ceramic capacitors are also from Aliexpress, I somehow broke a couple of the digikey ones when desoldering and didn't have enough, so I thought I might as well use all from the same manufacturer, perhaps for no good reason at all
- the chip is new, I didn't bother desoldering it from the first board, but I bought a couple spares in the first place since I was most afraid of messing up this part
- JST socket is new I bought locally, the original one looked rough after desoldering, even if probably functional
- you might notice that the Service button is different from the Test button, that's because the original one was broken! (that was the only thing that didn't work right off the bat on my succesful attempt, so I replaced it with another I had around) - I'm forced to assume I somehow broke it while desoldering as well, but it looked fine visually so this one really surprised me
- bipolar capacitors are by Panasonic, since Nichicons from the BOM seem to be not available anymore
- I read in this thread that the slide switch is wired backwards, so I used a generic one I bought locally instead which seems to behave more intuitively
- I replaced the LED with a generic green one I bought locally - I don't like blue LEDs, they're painful to look at!

Many thanks for coming up with this project, it was indeed pretty satisfying to finally get working. Now was it easy for a beginner? I was certainly encouraged by many people in this thread that said something to that effect but I'm not sure "easy" is correct, maybe it would be more fitting to say it's tough but definitely achievable (and I may have had something working on first try but I'll never know, I didn't even test the attempt with the crooked connector :P).

Some thoughts/questions/observations:
- contrary to many people here, I think I actually had the hardest time with through-hole components - SMD might be small and might require some precision, but I got some practice from Aliexpress kits after the first attempt (someone earlier in the thread asked about what to do for practice if not another minigun - there's absolutely loads of DIY electronic kits available there for cheap, including SMD, I highly recommend), and I think I'm decent at it by now, but for some reason THT soldering in this project was harder - there were some joints that simply didn't want to work, and I didn't have this problem this frequently on any practice kits I tried before that - solder just didn't want to stick and I got very obvious cold joints. I eventually resorted to just using a copious amounts of soldering paste before even trying the next ones and it kinda worked out, but that runs contrary to the experience of other people here (easy and kinda fun, not at all sticky to clean up :P) The only thing that makes sense to me is that the joints just didn't get enough heat quickly enough before flux from the wire burned off, and I do recall reading that on real circuits there is more heat sinks like ground planes that can make it a problem so maybe my soldering station is just not powerful enough? I have a 40W one, do you all guys have more powerful ones, or any other tips on what could I have been doing wrong? I tried to make a decent contact with both the pad and the leg, and melt solder on the connection between the two and all that stuff, so I think my basic technique should be correct.

- is it documented anywhere what each of the 4 mini dip switches do exactly? From playing around with them myself and reading the thread I think the first two are for button 4 and 5 from JAMMA edge, and I'm guessing the other ones might be related to the kick harness (which I can't test), but I think it would be nice if this was clearly documented somewhere (unless I missed it?)

- the heatshrink from the digikey BOM doesn't actually fit all that well on the fork terminals from the BOM - I had an extremely hard time sliding it over the bigger insulated part (you can see on the picture that I only managed to pull it all the way through for the red one, I gave up halfway for the other ones, and for AC I used different tubing I had) - it's an extremely tight fit. I saw no one else mention this (I guess heatshrink tubing is cheap and plentiful elsewhere, I got it mostly for free digikey shipping)

- turns out crimping Molex pins is nigh impossible without a good crimping tool - I gave up and soldered it, and folded the bigger wings over the insulation with pliers


Good luck to anyone else attempting this, if I managed to do it you probably can too!
 
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Great work on the build, it’s looking good!

The Minigun is definitely doable as a DIY project but you will need some practice before you build it. Given most components are through hole it does make it easier than trying to build something with lots of 0805 SMD components

The wattage on most soldering irons is the power of the device itself, and if you have an iron with a ceramic heater your soldering tip is going to have a hard time maintaining temperature. The quality of the tips also makes a big difference here

If are planning to do more similar projects I would recommend a more powerful unit with better thermal recovery and higher quality tips like a Hakko FX-888D, or a TS100 or similar unit where the soldering tips are cartridges that contain the heating element

The switches are documented and are labelled on the board - they turn button 4/5 or off for player 1 and player 2 for those games that can have issues

Heatshrink is supposed to be a close fit and then gives good protection of the connection underneath once shrunk but can sometimes be too small. If the recommended size just go one size bigger. It’s very easy to find even at local electronics retailers

Yes, pins on wire harnesses are very difficult to crimp without the proper tool, it can be done but it’s not worth it. If you’re only doing 1 or 2 it’s easier to just buy a premade one (a lot of people on here will happily make you one for a small fee) or if you are planning on making your own moving forward you can get a good quality crimp tool from Aliexpress for about $30USD
 
Nice job on the MiniGun. If you were having problems soldering the through hole components it could definitely be equipment. @xodaraP gives a good recommendation for this type of work. I think the Yihua 982 is available on aliexpress cheaply, is reasonable quality and takes cartridge tips. Just be careful as some take C210 cartridges and other C115. I personally use similar to the C210.

For this work I typically use a fine hooked tip and 0.3mm solder for SMD parts and a blade tip and 0.5mm or 0.7mm for the through hole, but through hole can be difficult without the correct technique with a small tip and i can definitely notice it when i am not making good contact with either the pad or part. Something to maybe consider is that heat transfer through molten solder is more efficient than through the iron. With some of these joints I really just put a small ball of solder on my tip, if you are making good contact with both the pad an part it sort of finds its own place and you can sort of see when it flows through the hole to the other side as it shrinks a little. If you have a cold part or pad it just stays on the tip or parts that are hot.

I do SMD like this also, while I have seen people put a blob on a pad and slide the part in while it's hot. I find it easier to put a small amount of solder on my tip and while holding the part in place with tweezers touch the pad and part briefly. This is also how I do small ICs like the THS7374 on the minigun. When you get good at this technique you can sort of put the blob on the tip while the iron tip is on the part (if that makes any sense). I tried learning SMD many years ago using the blob method and it wasn't until I switched to my method that I could really master fine pitched stuff. Each to there own just remember there are many ways to do things.

Nice job
 
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- is it documented anywhere what each of the 4 mini dip switches do exactly? From playing around with them myself and reading the thread I think the first two are for button 4 and 5 from JAMMA edge, and I'm guessing the other ones might be related to the kick harness (which I can't test), but I think it would be nice if this was clearly documented somewhere (unless I missed it?)
Amazing work - so satisfying to look at something like after its made and know exactly how it was made. Congratulations!

To answer your question those DIP switches are to control the behaviour of some of the player buttons
Specifically
P1B4 = Player 1 Button 4
P1B5 = Player 1 Button 5
P2B4 = Player 2 Button 4
P2B5 = Player 2 Button 5
By default (dip on) the button presses will go to BOTH the Jamma edge and the kick harness header.
Normaly the default is desirable behaviour. JAMMA is 3 buttons per player, many common boards are Jamma, but not exactly and not all of them. For example NeoGeo is JAMMA like (4 buttons + change game, no kick harness), some boards are JAMMA+ (5 buttons no kick harness), CPS2 is 6 buttons per player (with kick harness), and various other weird combinations.
Defaulting to "both" saves a lot of fiddling around.

But there are a few games that insist on one or the other, but not both
For example it is not possible to do Akuma "raging demon" in SF2T with the DIPs set to both. The punches must come only from the JAMMA edge and not the kick hardnes, and the Kicks must only come from the kick harness, not the JAMMA edge
There are other examples too but I forgot them, maybe someone more knowledgable than I can fill the gap

TL;DR - for those rare cases where a system insists on only having kick input on the kick harness and specifically not on the JAMMA edge the DIP switches allow you to control this behaviour.
 
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For example it is not possible to do Akuma "raging demon" in SF2T with the DIPs set to both. The punches must come only from the JAMMA edge and not the kick hardnes, and the Kicks must only come from the kick harness, not the JAMMA edge
Oh wow I thought I was just terrible with a joypad when not able to do this when running the minigun on the test bench.
 
A couple of cased ones left, if anyone is interested see my sale thread or DM me. I also made a stl for some button extensions for anyone who already has a minigun without the pacifier shell and wants to add a shell. This just brings the service and test buttons to the top shell (see pictures), you still need a 'thin' trimpot tool for the rgb pots, a pair or tweezers for the mono/stereo jumper, a tooth pick for the b4 & b5 dips and the lpf switch, and a lot of patience for the kick harness. I couldn't find a solution to those. I like it without a shell as all those things are easy to access but I know some prefer a shell still. DM me if you want the button extension stl. It's is such a specific thing so I will keep it of thiniverse and I couldn't really find a place here to post it that made sense either, but happy to share.
 

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