Donkey Kong power adapter hack for switching power supplies

wantdataeast

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One of my first stops for a replacement switching power supply is Arcade Shop because of their snazzy plug and play adapter. Unfortunately they are out of stock at the time of this writing. So I decided to make my own. I opened my old Donkey Kong jr power adapter to harvest goodies. I used my dremel to chop off the factory power adapter plugs.

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I pulled an Arcade Shop adapter from another Donkey Kong game I had previously installed and toned out the four values 5, -5, +12, GND.



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(note: at the time of the above pic i had the jumper set to send 12v to the coin counter, this is not where I normally keep it. And set as seen above sends 12 vdc to the NU pin at 9P. I wrote the values on my diagram when jumper was in the OFF position, which i think most of us keep it. So ignore where my jumper is set and pretend it is in OFF position when you look at my value at 9P. No other value changes other than the NU spot on 9P when you change the jumper).

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Red 5v
Blue -5
Orange 12v
Black GND
(if you wanted to send 12 v to the coin counter you would ad another orange wire to the NU position on 9P)

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I attached a little piece of plastic to the back of the adapter to cover the exposed connections, a coating of silicone would also do well here.

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BONUS:
I was treated to a BONUS inside my old power supply. A rainbow wire interconnect power wire (which I also needed) to link power between my 2-board stack at P3 (video board) and P12 (CPU board), it was a 12 pin wire, so i just trimmed off the red and brown wire.

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Most switchers don't provide enough amperage on the -5V to run DK/Jr reliably.
Yes that is apparently a problem on occasion, but not enough of an issue to prevent numerous sellers to make Nintendo adapters and sell them with switching power supplies; so they obviously often work. Rebuilding the original Nintendo Power is apparently the correct way to go. The above guide would be for some that lacks the ability to rebuild a power supply, has an extra Nintendo power handy, or hacked one, etc.
 
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Valid point. I ran across this when using a VL switcher and running DJ, Jr and DK3 in the same cab. I'm think a HD switcher like we use for MCR Midway games would be more appropriate.
Most switchers don't provide enough amperage on the -5V to run DK/Jr reliably.
 
Valid point. I ran across this when using a VL switcher and running DJ, Jr and DK3 in the same cab. I'm think a HD switcher like we use for MCR Midway games would be more appropriate.

(Most) MCR games don't even use -5V.

I wouldn't use any supply that doesn't regulate the voltages individually.
Arcade supplies tend to only regulate +5V and the other voltages move around when you adjust it.

That's why I started making power supply adapters for AT and ATX computer power supplies 20+ years ago, but now AT power supplies are really hard to find and modern ATX supplies eliminated the -5V, and the -12V rail often doesn't supply enough current to re-regulated it down to -5V (although a DC-DC converter could prob take care of it).
 
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