Another one bites the dust.....

myersn024 · Post by **myersn024** » Fri Jan 12, 2007 11:27 am

As everyone here is surely aware of, the portabilizing process leaves many systems dead, fried, charred, or, in my case, all of the above. I picked up a mini SNES a few days ago at a junk store for a sweet price. I took it home and hooked it up and it worked flawlessly. Then it was time to take it apart. Everything worked fine up until I hooked up battery power and my screen. The damned thing just wouldn't come on. I tried everything...rewiring the capacitors, testing continuity between power and ground, measuring voltage across the capacitors to make sure they weren't fubar'ed. Everything checked out, but it just wouldn't work. This being my first attempt, I'll just chalk it up to experience. However, I just wanted it to play in the car or to take with me to my in-laws house and not take up one of the TV's, so I've come up with an idea better suited to my needs. Below is a conceptual drawing of what I'm going to do.

<img src=http://www.austinbull.com/pictures/concept.gif>

I know it really isn't anything more than a hipgear for a SNES, but it'll serve the purpose I want it to. Plus it'll fit in a laptop carrying case so it'll be plenty portable for me. Also, If I wire the controller right, I could use it for the NES also. Now to come up with a name.

*EDIT*
Does anyone know if anything lower than 10V can be input through the power port on on back of a SNES? I know that one can run off a lot less, but I didn't know if there was any special circuitry between the power port and the 7805 that would cause anything less than 10V to not work.

Website · Post by **Life of Brian** » Fri Jan 12, 2007 1:20 pm

Question about when you tried hooking it up the first time - exactly where on the board did you connect for ground? This threw me the first time I did it because there was a mislabeled picture in Ben's book I was going off of before I knew how to test for what was ground or not.

myersn024 · Post by **myersn024** » Fri Jan 12, 2007 1:27 pm

I started at the place where the book said to connect it and that didn't work. Then, tested for continuity between the middle pole of where the 7805 what supposed to go and found that I had it in the wrong place. So, then I tried it both at the right place and on one of the grounding strips. Neither place worked. I think I fried it the first time I connected power when everything was wrong.

Post by **marshallh** » Fri Jan 12, 2007 7:02 pm

You should be able to wire anything from 7.5v to 20v into the SNES, nothing else uses the line voltage.

myersn024 · Post by **myersn024** » Fri Jan 12, 2007 7:11 pm

I must have the crappiest luck ever. I opened a full size SNES this afternoon just to see what its innards looked like. I was suprised to see that it isn't just a whole lot bigger than the SNES mini. It is more semetrical and a lot flatter than the mini if you were to remove all the shielding, a/v port and DC input jack. This one was one that didn't have the separate audio board though. I can only imagine how much of a PITA it would be to rewire that thing. All that aside, here's the crappy part. After putting it all back together, it didn't work either. I was a little distraught. However, I broked out the multimeter and found that there wasn't any voltage getting to the 7805. In light of that, I hard wired power straight to the 7805. Then I anxiously plugged power in and nothing happened. Then I realized that there wasn't a cart in the slot, so I put one in and restarted it and it came on. So, it isn't perfect like it was before I just had to open it up, but at least it still works.

Post by **Triton** » Fri Jan 12, 2007 7:36 pm

I can only imagine how much of a PITA it would be to rewire that thing

yes it is! 22 wires is no fun lol, if you wanna see a nightmare fo wires check out the snesP i ws working on using an original snes instead of the mini, it was 7.75 x 5.5 x 1.75 inches!

you cant see the wiring for the audio board but you get the idea

Krepticor · Post by **Krepticor** » Fri Jan 12, 2007 9:51 pm

check the legs of the 7805 and make sure they read properly, If not then jump 7.2 volts from the main power inlet

This happened to me and it helped out

myersn024 · Post by **myersn024** » Fri Jan 12, 2007 9:59 pm

Krepticor wrote:check the legs of the 7805 and make sure they read properly, If not then jump 7.2 volts from the main power inlet

This happened to me and it helped out

I just soldered a battery lead straight to the 7805 in the SNES. I put the positive lead going to the unregulated input and the negative lead going to the ground leg. Works like a champ and only draws about 300 milliamps.

myersn024 · Post by **myersn024** » Mon Jan 15, 2007 1:51 am

I figured out today what happened to the SNES mini that I spoke of in my original post, but it was too late and the garbage man had already picked up the trash. Here's what I think happened. For some odd reason, Nintendo decided to use a power supply for the SNESes that has the positive wrapped around the ground, making what is normally the ground on other power supplies the hot and vice versa. I didn't figure that out until a little earlier today. As a result of not knowing this, when I tested the SNES mini after rewiring the capacitors and removing the DC and AV jacks I applied reverse polarity power to the 7805. In case you don't know, reversing the polarity of the input and ground legs on a 7805 will fry it so fast that your head will spin. So, instead of messing up the SNES mobo all I did was burn up a 7805. I didn't even think that could have been the problem since I didn't realize that I'd done anything wrong. It makes me feel better to know that I didn't tear it up, but I wish I would have figured it out sooner so I could have gotten it out of the trash.........oh well, we live and we learn. I'll just chalk it up to experience and move on to the next project. Maybe a PSoneP, Gran Turismo and Tony Hawk's Pro Skater 2 are calling my name.