PART 1: Adding a coaxial power jack to your flash
Okay! I finally got around to adding the jack to my Sigma EF-500 DG Super flash. I totally voided my warranty, but all in the name of DIY! Here is part one of my DIY guide to building your own external battery pack. The pack will consist of 8 AA's that can be used with the 4 inside, or without, much like the CP-E3, I believe.
NOTE: I am just a poor college student with limited knowledge of electrical engineering, but I like to try and apply concepts I'm learning in my classes. I'm actually studying mechanical engineering, so bear that in mind as you read my DIY guide. There are probably better ways of doing this or improving on the method I will demonstrate below. Feel free to give me input and suggestions for improving should I ever try to do it again on another flash, or fix this one up more. Also, the pictures are taken using my 30D's on camera flash, so excuse the harsh flash in some of the photos or generally bad lighting.
The Ingredients: (1) Flash, (1) Size N coaxial Jack needed for PART 1
Looking inside, this seems like the best place to put the jack.
Here are the leads from the internal battery compartment.
The proposed spot for drilling
Used a drill with an 8mm counterbore bit.
After drilling, it looks like this with the jack installed. I was a little concerned that it was too close to the edge, but it turned out to be okay. If it wasn't that close to the edge, the jack might not have cleared the other parts inside the flash.
Soldered 22 Gauge wire onto the circuit board where the battery leads come through, and then onto the jack. The (+) lead goes to the outer shell of the jack and the (-) lead goes to the center pin of the jack.
Here it is put back together
The flash still works after installing the jack. I haven't built the battery pack yet, so PART 2 is coming once I gather more parts.