Question from Burney: Hello Arcade Guys. I’ve decided I’m going to try to get an arcade machine I’ve had for years working again. It’s a Double Dragon unit that has been blowing fuses. When it was given to me over a decade ago, it had a blown fuse that kept it from operating. I changed the fuse and it started working. It didn’t get used a lot. I used it mainly as a conversation piece.

About two years ago I got a multicade board to replace the Double Dragon board. My arcade cabinet has a JAMMA compatible setup and I’ve swapped out different boards before without trouble. When I fired the unit up last, it had not actually been used in about three years. It started fine except Double Dragon was playing upside down so I powered the machine down and changed a dip switch setting on the board to flip the image so that it displayed correctly. After I made the change and powered it again, the unit starting blowing fuses. It blew every single fuse I put into it. I went through about five before I realize that wasn’t going to fix it. I don’t know if I twisted a wire or something while I was flipping the board around but I don’t think a simple dip switch change like that would break the machine. I changed game boards and it still blew fuses. I bought a new switching power supply but that didn’t fix the problem. At that point I pretty much gave up on it; however, I have a new reason for wanting to fix it now. A friend of mine’s five year old granddaughter was really excited to see my arcade machine when she visited but was disheartened when I had to explain it didn’t work. My interest in it has been piqued again. I would like to get it working again and play that multicade board I’ve bought that just been collecting dust.

This is now my new little personal project: getting my Double Dragon machine working again!

I took electronics in high school and have dabbled with soldering and using multimeters before but it’s been years since I’ve done anything significant with them. Right now I’m practicing with these tools, just trying to remember how to use them properly (although, to be honest, I hope I can find a simple fix). I’ve been going through your videos and I’ve found the information provided in them helpful. It has taught me what a lot of the components in the machine are. I’m not done going through, but I do have a question for you. In my cabinet the bottom of it is covered in some kind of cardboard with a silver backing. This silver backing is conductive (I tested it with my meter and lest light) and the green ground wire going to the power line filter is screwed in such a way that it touches this silver backing. The isolation transformer in this machine is bolted right on top of this silver cardboard. It’s been like since I’ve had it. My question is: do you know what this silver backing is? Is it meant to provide a ground? I’d been told that short was probably causing the fuses to blow and I was wondering is something might be touching this silver cardboard and causing it to short. I was thinking about moving mounting everything (power line filter, isolation transformer, fuse connectors, switching power supply) off this silvered cardboard and mounting them to a piece of wood. Before I did anything like that though, I wanted to find out what that stuff was! I’ve not had any luck with Google, but Google did lead me to this web site so I’m hoping you can tell what I’m looking at (and stop me before I make some big mistakes). I don’t plan on moving any components until I’ve had time to review the rest of your videos and check with some other sources.

Many thanks for your time and help!
Burney