cheezmonkey
Member
Hello folks,
I picked up a broken Game Gear a while back to try and resurrect once I'd gotten used to waving a soldering iron around again. Having built a few DIY project kits and fixed a couple of things around the house, I decided it was time to have a bash at this thing a couple of weeks ago.
Well... I knew it didn't work and that the original owner could tell me nothing about why. That was fine, I Wanted it as something to sort out anyway. But my goodness, the battery acid. There were no actual batteries left in the thing, thankfully, but I wouldn't be surprised if that was becuase they had entirely disintegrated and spread about the inside of it. The stuff was everywhere, even on the inside of front panel!
Much vinegar, IPA and cotton buds later, I felt a little safer touching the thing and set about giving it a good inspection. I could see a couple of the caps were leaking, so I decided to buy a capacitor kit and continue poking it in the meantime. Just for science, I put it back together and tried to turn it on. Nothing, of course. dead as a dead thing. No surprises.
As I Waited for my parts to arrive, I got to thinking, it might be worthwhile buying another broken one in case I need to scavenge some parts. Though I could see nothing obvious, the amount of leakage I found worried me that there may be parts to replace other than capacitors, a second unit may come in handy. So I picked up another "broken" one from a certain bay. This arrived in good time and the only thing "wrong" with it is that it has a few more dead pixels than one might like. This is even better, I thought, now I have a working sound board and power supply AND a case which doesn't look like it's been in a cement mixer.
With a gleam in my eye and a fire in my heart it set about gathering all the information I needed. Manuals, diagrams, parts lists - the works.
Again, for science, I stripped the working one and pulled out the power supply and sound board. I hooked them up to the bad board and tried to turn it on, the result was different to before - the screen was mostly white, but it was chaotically flashing and rolling. Clearly in a bad way. I unhooked it all and put away the good one for now.
Later, I very carefully removed the original capacitors from the bad machine and in so doing found a couple more which had leaked a little. Did a bit more cleanup with IPA and waited for my capacitor kit to arrive. It did, some short while later so I set about doing the replacements. As I have a known good sound and power board, I skipped them and focused on the mainboard. Once all the capacitors were replaced, I hooked it back up to the working power supply and........ well. The screen was stable as you like. No flashing, flickering or rolling. Surely I haven't fixed this? Lets go a step further then. Known good game cart inserted, sound board and speaker connected. Powered again and The screen was a stable as you like. No flashing, flickering or rolling. Just a bright white square of nothingness. Then I remembered I had the sound hooked up this time. Volume up. God awful garbled racket. Not like bad caps, I mean just noise. hmmmmmm
After some more poking, I learned that the contrast wheel seems to work, insomuch as it will make the screen go gradually from piercing white to black, but nothing changes whether a game is inserted or not, so I've clearly missed something. I've removed and re-replaced all the capacitors I'd worked on. One as backwards, I fixed that to no difference. I removed the odd one and powered the board up to see if anything changed, it did not. Presumably, if I'd removed the right one, the screen would have not come up or something, but the hand-drawn wiring diagram is a bit much for me, so I can't really tell whats what. I've attached some pictures of my embarrassingly amateur workmanship in the hopes someone might spot something stupid I've done.
Other than that, any tips around WHERE I should be looking for these symptoms?
I picked up a broken Game Gear a while back to try and resurrect once I'd gotten used to waving a soldering iron around again. Having built a few DIY project kits and fixed a couple of things around the house, I decided it was time to have a bash at this thing a couple of weeks ago.
Well... I knew it didn't work and that the original owner could tell me nothing about why. That was fine, I Wanted it as something to sort out anyway. But my goodness, the battery acid. There were no actual batteries left in the thing, thankfully, but I wouldn't be surprised if that was becuase they had entirely disintegrated and spread about the inside of it. The stuff was everywhere, even on the inside of front panel!
Much vinegar, IPA and cotton buds later, I felt a little safer touching the thing and set about giving it a good inspection. I could see a couple of the caps were leaking, so I decided to buy a capacitor kit and continue poking it in the meantime. Just for science, I put it back together and tried to turn it on. Nothing, of course. dead as a dead thing. No surprises.
As I Waited for my parts to arrive, I got to thinking, it might be worthwhile buying another broken one in case I need to scavenge some parts. Though I could see nothing obvious, the amount of leakage I found worried me that there may be parts to replace other than capacitors, a second unit may come in handy. So I picked up another "broken" one from a certain bay. This arrived in good time and the only thing "wrong" with it is that it has a few more dead pixels than one might like. This is even better, I thought, now I have a working sound board and power supply AND a case which doesn't look like it's been in a cement mixer.
With a gleam in my eye and a fire in my heart it set about gathering all the information I needed. Manuals, diagrams, parts lists - the works.
Again, for science, I stripped the working one and pulled out the power supply and sound board. I hooked them up to the bad board and tried to turn it on, the result was different to before - the screen was mostly white, but it was chaotically flashing and rolling. Clearly in a bad way. I unhooked it all and put away the good one for now.
Later, I very carefully removed the original capacitors from the bad machine and in so doing found a couple more which had leaked a little. Did a bit more cleanup with IPA and waited for my capacitor kit to arrive. It did, some short while later so I set about doing the replacements. As I have a known good sound and power board, I skipped them and focused on the mainboard. Once all the capacitors were replaced, I hooked it back up to the working power supply and........ well. The screen was stable as you like. No flashing, flickering or rolling. Surely I haven't fixed this? Lets go a step further then. Known good game cart inserted, sound board and speaker connected. Powered again and The screen was a stable as you like. No flashing, flickering or rolling. Just a bright white square of nothingness. Then I remembered I had the sound hooked up this time. Volume up. God awful garbled racket. Not like bad caps, I mean just noise. hmmmmmm
After some more poking, I learned that the contrast wheel seems to work, insomuch as it will make the screen go gradually from piercing white to black, but nothing changes whether a game is inserted or not, so I've clearly missed something. I've removed and re-replaced all the capacitors I'd worked on. One as backwards, I fixed that to no difference. I removed the odd one and powered the board up to see if anything changed, it did not. Presumably, if I'd removed the right one, the screen would have not come up or something, but the hand-drawn wiring diagram is a bit much for me, so I can't really tell whats what. I've attached some pictures of my embarrassingly amateur workmanship in the hopes someone might spot something stupid I've done.
Other than that, any tips around WHERE I should be looking for these symptoms?
