Dumb Question - What makes a Happ/SUN PSU special?

varjak0

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I've tried googling this and the answers have basically culminated to "They're just good power supplies" but... why?

What's different inside? What do they do differently that your standard ATX can't? I'm gonna be using them for my Naomi's because I've just been told that's the right thing to do (and tried ATX and it didn't work).

I know the voltages are adjustable but is that the only difference? I think there's something about the rails (whatever those are) inside and the Happ/SUN ones have a rail for each voltage or something.

I know this is probably a real dumb question but everyone starts somewhere. I'm just looking to learn.
 
Nothing. They are pretty much the same as others, with more markup.
 
The SUN PSUs tend to have the correct voltages for JVS support, plus adjustment for each rail. It depends on the model specifically. SUN also has a reputation for quality as well.
 
I've tried googling this and the answers have basically culminated to "They're just good power supplies" but... why?

What's different inside? What do they do differently that your standard ATX can't? I'm gonna be using them for my Naomi's because I've just been told that's the right thing to do (and tried ATX and it didn't work).

I know the voltages are adjustable but is that the only difference? I think there's something about the rails (whatever those are) inside and the Happ/SUN ones have a rail for each voltage or something.

I know this is probably a real dumb question but everyone starts somewhere. I'm just looking to learn.
when you say ATX, you mean a PC power supply? those kind of have dangerous amperage levels. years ago when people were converting those to work with NAOMIs they were adding fuses to the +5V and +12V lines for that purpose.

but if you meant ATX like a 200W Happ PowerPro, the addition of +3.3V line is all the difference. Happ doesn't make anything like that, you can only use that "Tekken 5" (which doesn't even need 3.3V) Peter Chou power supply.
 
when you say ATX, you mean a PC power supply? those kind of have dangerous amperage levels. years ago when people were converting those to work with NAOMIs they were adding fuses to the +5V and +12V lines for that purpose.

but if you meant ATX like a 200W Happ PowerPro, the addition of +3.3V line is all the difference. Happ doesn't make anything like that, you can only use that "Tekken 5" (which doesn't even need 3.3V) Peter Chou power supply.
Yes, by ATX I mean your standard pc power supply.

That particular Tekken 5 power supply is what Ken recommended to me which is why I'm using it. Plus the 3.3v it has means its plug and play once I've made the wiring loom.

I guess I was wondering if there was anything different going on inside to distinguish your average pc power supply vs Happ/Sun.
 
Sun is a good unit. If you can recap and fan it, it should last another 20 years. Happ 44-1095-01 is a good cheap sub with easy to adapt harnessing. The key thing is you can set proper voltages at load on both of these units. With a PC ATX unit, these regulate using circuitry in a PC. Whatever you are planning to use the Sun or Happ unit on is not a PC. How will you get it to regulate?
 
PC power supplies are now generally designed to put out most of their power on the 12V rail. As an example:
1723762847133.png

Now, everyone will be quick to point out that a normal arcade board set is not going to pull anywhere near 18A on the 5V rail and so the above supply will be fine right? Well, what is not show in that graphic is that pretty much every PC power supply will require a minimum load on one or more of the power rails to regulate properly -- these days, it's the 12V rail -- and it's generally not a small load either, sometimes being as much as 10% of the rated output. Good luck finding it documented too. That's going to be the biggest issue using a current PC power supply. They aren't adjustable either, so you can't boost the power supply output to make up for wiring and connector losses -- though really you should be looking at fixing the losses.

Considering you can get a dual voltage MEAN WELL for less than a decent ATX supply, and a Suzo Happ for not much more, the pain of trying to make an ATX computer power supply work just isn't worth the effort, IMHO.
 
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