The bottom of the cartridge is the wrong size:
Normally I solve this problem with something called a "super adaptor," all it really does is run the cartridge through a long circuit board designed to fit in the super famicom.
Normally this works great, but for some reason, doing this with a SuperGameBoy seems to produce graphical glitches - scanlines and garbage.
This was pretty annoying. It took me awhile to figure out it was the presence of the super adapter, and i'm still not sure why it happened. I cleaned it thoroughly, I tested the pin connections with a multimeter, everything seemed fine. It SHOULD have worked, but it didn't. Eventually I took the Super Game Boy out of the plastic case and plugged it into the Super Famicom directly, and it worked perfectly!
I could have continued to use it like that, but I like to have my games protected by something when i'm not using them - and best way to do that is to have it in some sort of case - so I decided to make a new one.
Now my Super-Gameboy is in the remains of an old NES GOLF cartridge. I had to shave part of the circuit board down and it just BARELY fits, but it works. Pushing the cartridge into the system takes a little force, but it's not bad. I might have to modify it further, i'm not sure where the resistance is, but it's no big deal, once you learn the quirk it's easy to take the cartridge in and out. The eject button does not work with this cartridge.
Best of all, it still works - with clear graphics!
Here are some shots of it outside of the system:
It's pretty roomy in there. The SGB circuit board is pretty small. Because it's made out of an NES cartridge, i'm afraid I might get it mixed up with my nes games. If you are nuts like me and you decide to do this, make sure you don't cram it into the wrong system.
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