Transforming a Gameboy

One of my work colleagues read about my Gameboy fiddling and kindly posted up one of his old grey DMGs that was destined for the charity shop to see if I could do anything with it. I decided to document its transition.

It was in the kind of standard condition for a used Greyboy of its age. The case was a bit roughed up and the LCD screen had vertical lines of dead pixels at either end. You can make them out below.

First things first was to see if I could fix that, as if the screen was dud, it would only really be worth spare parts. Luckily, it’s a pretty simple job, and before long the screen was as good as new.

With that, it was time to set about preparing the screen to put a backlight in. The old Gameboy screen was always a nightmare to see, so installing a new LED light source is a must. It’s also a tricky process, involving removing the foil back off of the screen itself. One wrong move and you can trash the whole thing. As it turned out, the adhesive on this particular Gameboy hadn’t corroded away, meaning it was a pretty smooth and simple process.

Then I put the Gameboy guts into a new case: transparent orange, which is a colour that was never available for the DMGs back in the day as far as I’m aware.

Next up, I installed a hex inverter chip to ‘bivert’ the screen. The new backlight polarising filter inverts the screen already, and so this step inverts it back to the regular display type, increasing the contrast in the process. It’s fiddly, but drastically improves the clarity. I’m pretty blind, so any picture improvement is a win.

It took a while as I didn’t realise that the backlight kit was missing a crucial resistor, and I had to go through each step to test it all again. A good lesson in not trying to do too many things at once.

Here’s the screen all lit up and biverted.

Next was installing a pitch oscillator that I had had lying about for ages. In other words, a small knob that changes the clock speed of the Gameboy to run faster or slower. What’s the point in that? For games it helps speed up boring parts that you can’t skip, but for music it lets you slow down or speed up things with the corresponding pitch change. Pretty damn cool.

The potentiometer fits into the space where the speaker sits, so it had to go.

I included a switch to turn the pitch oscillator on or off, which turned out to be a bit too big for the case…

I also wired up two RCA jacks for line level audio output. This wasn’t the ideal place to put them, but space was tight because of the other mods. I had begun to install a 3.5mm line out in the same position, but realised that the plastic seemed to be much thicker than in the other model I had done this on, and so the barrel was too short to fit through. RCA it is!

There was a lot of wires in there by this point. Just for fun, I decided to throw in some orange LED lights to give the case a nice glow. By the end of that, it was a bit tricky getting the case to go back together neatly.

At least I used appropriately coloured electrical tape…

So after a good few hours working on this beast, spread across a few days, here’s the finished result:

The case cutting and drilling leaves a lot to be desired, with rough edges obscured by the buttons and pots… But you can’t really notice. Despite that, I’m pretty pleased with the end result. Everything works, I learned a fair bit, and an old Gameboy has a new lease of life.

Modding Gameboys Again

Inevitably, a big part of making chiptune music involves exploring what you can do with different hardware, and how you can get the most out of it.

Whilst dragging out my gear again, I realised that I have a whole bunch of components kicking about from half-finished projects that I never quite got around to completing: Gameboy screens, shells, lights, switches, and other bits and pieces.

I want to modify my Gameboys so that they all have at least a backlight, and try out some other more interesting things like installing oscillators, so I thought I’d have a bash on one of the reliable bricks that I had lying about in pieces, and install a backlight in an otherwise unmodified yellow DMG.

I battered through the first bit easily. The foil that you need to peel off the screen for the backlight to fit came off without any hassle or residue left behind, and I remember thinking how much simpler it was than the last time I did it.

I should have known better though. Despite getting everything wired up fine, the screen wasn’t showing anything at all. Luckily, I have a pile of spare Gameboy guts to test things out on.

After a bit of swapping about, I realised that it was the screen itself that was the problem. No big deal, though the other screen I had to hand with the foil removed had a damage mark right in the middle that meant it wouldn’t be of any use for the final product. I’d need to remove the foil from one of the others.

For reference, here’s what the screen looks with an inverted backlight…

And without the inversion:

I dug into one of the other spare innards, only to find that the screen was warped and wouldn’t work. Damnit. That left just the one spare without cannibalising another body. I prised the foil off with a razor blade and after about half an hour of scraping/soaking in contact cleaner, got the crusty adhesive residue off.

After putting the damn thing together and taking it apart a few times as I discovered other minor issues (the buttons not fully depressing because of the wires to the LEDs etc), and fixed them all. Eventually, we have the finished product:

A working, old-school DMG with a lovely blue LED backlight so that it can be used anywhere. In the future I plan to add a hex inverter chip to make the screen more contrasty, as well as some other bits and pieces – but for now I’ll leave it in peace.

I knew absolutely nothing about physics or electronics before I took apart my first Gameboy, and I’m definitely not an expert, but there’s something pretty satisfying in putting together or modifying the hardware that you then make music on; squaring the circle or something like that. If I can work it out, then surely anybody can.

All in all, it took longer than I expected, but also wasn’t as complex as I remember from back when I was learning the basics. I’m looking forward to seeing what I can pull off in future.