When I added mods to my JD, I immediately ran into power issues. I ended up buying a meanwell power supply and fed it off the service outlet of the machine with a plug that turns on with a relay (which I tapped off a coin door light). I then used the meanwell to supply power to one of the aftermarked 8 plug expansion boards and ran everything I added to the game off of that. Worked like a charm. The only thing aftermarket that I ran off the original power was my ColorDMD.

I'll try to find links of what I bought and followup with them. This was a couple of years ago so memory is foggy on what and where I bought them.

Here is the Meanwell power supply I use and have installed it in several pins with the same installation as described above. Just better to pull mod power off of a dedicated source rather than the machine's power.

https://www.amazon.com/Power-Supply-Dual-Output-Volt/dp/B005T7EZM8

Here is the power splitter I used. I used these in non-Stern pins as well. I just bought extra pins and connectors and wire everything to plug directly into this board.

https://www.pinballlife.com/8-way-power-splitter-board-for-stern-pinball-machines-using-whitestar-or-sam-operating-systems.html

And then this is the relayed power cord that I used to get the Meanwell to turn on and off with the machine. Unfortunately, it looks like it is no longer being made: https://www.adafruit.com/product/268

They have this as an alternative which does exactly the same thing, but its a bigger footprint with 4 outlets: https://www.adafruit.com/product/2935

I also remember seeing somewhere (on here??) that someone is/was selling a similar relayed cord that powers up when it detects light. So when you turn on your pinball machine, it detects the lights from the game and completes the circuit through the cord. But I cannot seem to find it right now.

Anyway, hope this helps. It really is not difficult to do. The Meanwell gives you both 12v and 5v, so just make sure that you power whatever you are hooking up correctly. Those 3 pin connectors are a 12v, 5v, and ground pin. Pretty much everything I had hooked up used 5v. So I didn't run the 12v pin in most of the plugs I ran but I did supply the 12v to the power splitter just in case I ever needed it.

Instead of a relay you can put the extra power supply on the other side of the power switch so it powers on/off with the rest of the game.

And now that I look at that alternative relayed power cord, it's nice that it has 2 "always on" plugs and 2 of them are relayed. I lost my service outlet with the old plug because my cord took it to power my Meanwell. With that 4 plug, you will actually have 2 service outlets now without having to unplug anything. Not too bad. I would just unplug my cord when I needed to solder something, but extra plugs are not a bad thing. Plenty of room in the JD cabinet, so its not really much of an issue.

NOW you tell me...

Or this

https://www.rockcustompinball.com/product-page/game-on-power-supply

The line cord and power button ultimately puts 120v onto the transformer primary. You can add two wires at that exact same point going into the transformer to feed the input on an extra power supply for mods.

If you need a lot of power for mods, its hard to beat a 360W (30A@12V) power supply for under $25
https://www.amazon.com/gp/product/B06XJVYDDW/ref=ox_sc_act_title_1

To put it in perspective, most LEDs take as little as 5mA or up to 20mA each, depending on size and color. So for each AMP of power supply, you can add at least 50 larger LEDs, or up to 200 smaller LEDs. With adding a 30A power supply, you should be all set with adding 1500 BIG and bright LEDs. This is a great thing because it allows your pinball machine to double as an aircraft landing strip if needed! (In all seriousness, other mods may include motors or sensors and controllers which take more current as well).

This was the light activated one I remember reading about.... Thanks for posting that. I couldn't remember where I saw it.

JD came from the factory tapped out with its available power used already. I swapped all of my bulbs to LED and then was able to run a ColorDMD off the stock power. But after that, even plugging in 1 led strip or low draw mod and I was blowing fuses, getting resets, etc... If there is one game you should add an additional power supply to for anything extra, JD would be at the top of that list.

Any pics to this JD?

Victor Tan ("DumbAss" here on pinside) makes a WPC auxilliary accessory power supply board which has both 12 volt and 5 volt outputs. They are wired the same as connectors J116 through J118 on the WPC Power Driver board. It's good for 3 amps on each voltage rail. Here are pictures of the board and the particular wall wart power supply we ordered to operate the board.

WPC aux1 (resized).JPG

WPC aux2 (resized).JPG

WPC aux3 (resized).JPG

Not exactly sure which JD you were referring to, mine or the OP's... But if you were asking about mine, it was just restored by HEP and if you scroll down to the under-playfield pics, you can see that he wired the Meanwell power supply and the power splitter board in the restoration. The power splitter only has one thing plugged into it at the time of his pictures, but it will have a few more things plugged in when it gets back to me.

https://pinside.com/pinball/forum/topic/hep-this-week-9-17-18/page/186#post-6297106