Game Boy DMG-01 modding step by step guide

I just finished modding another Game Boy DMG-01 and this time I photographed the whole process so that I could use it for a step by step guide. Instead of going into details about the obvious mods, like replacing the screen (cover), buttons and silicon parts I will focus on the more technical aspects of modding.

Procedures

How to install a backlight
How to install a bivert chip
How to do the Prosound to headphones mod
How to do the bass mod
How to do the Decoupling capacitor on the powerstrip mod
Final results

What you need before getting started

  • Game Boy DMG-01
  • Soldering iron or Soldering station, preferably one with variable temperature
  • Solder
  • Desolder braid
  • Scalpel
  • Tri-point Y1 screwdriver
  • Cross screwdriver
  • Wire
  • Small chordcutter
  • Isopropanol
  • Cotton swabs
  • Polishing cloth
  • Game Boy Backlight kit
  • Game Boy Bivert chip
  • 1 Electrolytic capacitor 1000uF
  • 2 Electrolytic capacitors 10uF

OK lets get started.

How to install a backlight

1. Remove the polarizing film and reflective layer on the backside of the screen

Open up your Game Boy and remove all the screws from the two boards, then pull out the ribbon cable connecting the two halves.

Remove the two small screws below the screen. Carefully lift up the screen using a screwdriver or a small spatula tool in the little notch in the top of the plastic frame. There will be a little resistance because of two small adhesive pillows on the inside. When you have pulled up the screen enough to see them both, carefully remove them with a pair of tweezers.

Now you are going to pull off the polarizing film and reflective layer while trying not to break the screen and the solder points underneath the screen. This part can be a bit tricky so if it’s your first time I recommend to first try it out on screen that is already broken beyond repair, for example one with screen cancer.

 

Game Boy Backlight mod

The polarizer and reflective layer are glued together.  You will remove both of them in one take by inserting a sharp knife like a scalpel in the top left corner . The trick not to scratch the screen is to press in the knife just a few millimeters where the layers meet the glass. Then use the knife (pushing it outwards) to open up a corner big enough for you to grab with your thumb and index finger. Once you can grab it, start slowly pulling away more by moving your thumb inwards and along the sides of the screen.

Try not to exert to much force on the screen so that it bends. If it bends too much it will snap and become unusable. That happened to me once. The popping sound when that happened is not one I would like to hear again while doing a backlight mod haha. Also try not to put too push the screen too much away from the frame as this may damage the solder points under the screen. More about that later.

 

Game Boy Backlight mod

Here you can see how I have slowly worked my way towards the other side of the screen.

2. Clean the screen

With the polarizer layers finally off, best case scenario there is almost no glue on the screen. The cleaning process can take anything from 10 minutes to an hour depending on how much glue residue there is.

Use plenty of Isopropanol and cotton swabs in a circular motion to loosen up the glue and then drag the bits of glue off the screen. You may have to go through three to twenty cotton swabs depending on how much glue is left. The goal here is to remove all of it and it may take some time if you are unlucky.

 

Game Boy Backlight mod

When all the glue has been removed, there will still be some residue from the isopropanol on the screen. Clean that off with a very fine polishing cloth, like the one you would use to polish a car. Do not use toilet paper or something like that since that would scratch the inside of your screen. I use a technique where I apply some of my breath to it and quickly and carefully clean with the polishing cloth.

 

Game Boy Backlight mod

When you have cleaned and polished the inside of the screen it should look like this. You should see no streaks, dots, smudges or fibres left from the cotton swabs, even if you hold it up to the light.

3. Cut a hole in the plastic frame for the backlight connector

Use a small wirecutter tool to cut off a bit of the plastic big enough for the backlight connector to fit.

 

Game Boy Backlight mod

4. Solder the resistor and wire

I always use backlights from Deadpan Robot. It comes with a resistor that needs to be soldered to the connector where it says plus (+).

I have found that doing it like depicted in the picture below is the easiest and fastest way. Solder the resistor directly to the connector on the backlight and then bend it in almost 90 degrees to the right.

Game Boy Backlight mod

5. Install the backlight and solder the resistor and other wire to the board

Install the backlight by sliding it into the plastic frame under the screen. Remove the protective sheets on the polarizer and slide it in over the backlight, making sure you don’t scratch it. On the backlight from Deadpan Robot there is a blue stripe on the polarizer which indicate its backside. Also make sure the screen becomes dark blue after you have inserted the polarizer. If it’s not dark blue then take it out again, flip it 90 degrees and insert.

Now solder the resistor and the black wire to the board, like in the image below. It’s easier if you use a pair of tweezers to hold them in place as you solder. You may need to apply some new solder to make them stay.

Reconnect the CPU board with the display board, put them in your case without screwing everything back together, insert batteries and start up the Game Boy to see if it’s working. If it doesn’t look anything like the image below then something is wrong.

 

Game Boy Backlight mod

Closeup of the solder points for the backlight

Things that can go wrong when installing a backlight

Symptom: The block in the middle is dark blue and the screen is light blue.
Reason: Take out the polarizer, rotate it 90 degrees and insert again.

Symptom: There are strange kind of polarized circles and the screen may look not as sharp as it should.
Reason: You either forgot to remove the small pillows under the screen or the polarizer is upside down.

Symptom: The Game Boy starts up but the screen isn’t working, or it’s working but doesn’t show the block in the middle, or it’s working but the image is flickering  a lot.
Reason: This is a pretty common problem, especially with the first gen Game Boys, but much less with the Play it loud versions. You may have teared one or several solder points under the screen while cleaning it. You have to remove the backlight and have a look with a magnifying glass on those solder points. They can be re-soldered but it’s a bit tricky. Use low heat on the solder iron and be careful not to burn the screen in the process. One trick I’ve learned is to put a tiny tiny bit of gooey flux where the solder joint is broken, then put a tiny bit of solder on the tip of the iron and just quickly touch the solder point.

Symptom: There are vertical lines on the screen.
Reason: This is also a pretty common problem with the first gen Game Boys. There are some microscopic cracks in the connective parts of the plastic chord underneath the screen. It’s usually pretty easy to fix, but not always. Here’s a good video that shows you how.

Symptom: There are horizontal lines on the screen.
Reason: The plastic chord to the right of the screen has some microscopic cracks. This is much much harder to fix than the horizontal lines so I’m sorry to say your screen is a gonner. Sorry. If anybody have managed to fix this, please let me know, cause I have tried several times and failed.

How to install a bivert chip

Now it’s time to put in the bivert chip. This will make the Game Boy video look crispier and with less ghosting. I used the bivert mod custom circuit board from Deadpan Robot because it’s super easy to install. The bivert chip is pre-installed on a tiny circuit board that you just solder in place.

1. Desolder pins 6 and 7 on the video connector

Locate the video connector and desolder pins 6 and 7, as shown in the image below. I have tried different techniques on how to desolder them without breaking anything. I’ve found that the quickest way is to press a scalpel to one of the the solder point, then hold the tip of the solder iron on it, while I gently prying the scalpel underneath it. The goal here is to bend the two pins upwards and break their existing connection to the board.

2. Solder the pins to the bivert chip and the other solder points

When both pins 6 and 7 are de-soldered and slightly bent upwards I put in the bivert chip board and re-solder both pins to it. It’s pretty small and tricky so you may need to use a magnifying glass here. When both pins are soldered I then continue with the other four points on the bivert chip board.

 

Game Boy Backlight and Bivert mod

 

3. Reconnect the Game Boy

It’s time to see if the video is still working. If it looks like the image below then you are in the clear.

 

Game Boy Backlight and Bivert mod

Things that can go wrong when installing a bivert chip:

Symptom: No video or video looks strange, flickers etc.
Reason: Most likely either one of the solder points on the chip doesn’t connect with the board or you accidentally made a bridge somewhere with pins 6 and 7. First, try adding some heat to the solder points on the chip and perhaps add some more solder. If that doesn’t work, try re-soldering pins 6 and 7. Last resort would be de-soldering the whole chip and do it all over again.

How to do the Prosound to headphones mod

With the prosound mod you get a better sounding Game Boy. It’s done by sending the sound directly to the headphones, bypassing some internal circuitry that otherwise adds unwanted noise.

 

Game Boy Prosound mod

This one is so easy I won’t write a step by step for it. Just cut and remove the two black wires shown in the image. Then solder two new wires as also shown in the image.

 

Game Boy Prosound mod

Solder the black wire to solder point number 3 and the red wire to solder point number 4. The are pretty small so what I do first is apply some solder to them. I keep the tip of the wires pretty small and apply solder to them before soldering them onto the board. Be careful not to hold the iron for very long on the solder points or you may break them. They are very tiny and delicate.

When done, reconnect the Game Boy and start it up with a game. Listen to the sound and try lowering and boosting the volume to make sure there are no crackles and other strangeness going on soundwise. Also try out with the headphones to make sure you have sound there as well.

Things that can go wrong after having installed the prosound mod:

Symptom: No sound.
Reason: Check so you have soldered to the right solder points.

Symptom: It sounds strange, there is crackling etc.
Reason: Check for short circuits, try to re-solder the solder points.

How to do the bass mod

The bass mod adds a bit of sub bass in the lower ranges, like 40-50 hz. You would typically need a good pair of headphones or a sub to notice the change, but it will definitely sound beefier on a club sound system.

 

Game Boy Bass mod

1. Locate the two 1 uF capacitors on the CPU board

You will find them close to the volume wheel.

 

Game Boy Bass mod

2. Desolder the capacitors

Turn the board and desolder the two capacitors. The easiest way is to use a desoldering braid. Make sure it’s not too big. I think the one in the image above is something like 2 – 2.5 mm wide. If possible, lower the heat on your solder station a bit, place the braid on a solder point and put the solder iron over it. These points are delicate and pretty easy to break if you apply too much heat for too long, so try to be careful with this one.

 

Game Boy Bass mod

3. Remove the old capacitors and solder new ones

When desoldered, it should look something like the image above. Turn the board, remove the old capacitors and put in two 10uF instead, making sure to put the leg for + where it says + on the board.

 

Game Boy Bass mod

4. Success

New 10uF capacitors are soldered in place and the solder joints are looking good.

Bass mod completed.

Not much can go wrong here except for applying too much heat while desoldering and breaking the solder points.

How to do the decoupling capacitor mod on the power strip

This mod is done to improve sound quality after having installed the prosound and backlight mod.

First you need to get hold of a electrolytic capacitor in the range of at least 500-600 uF, although I recommend to go for a 1000uF. I have tried a different values and found that 1000uF produces the best results, in regards to the reduction of hiss and noise.

 

Game Boy Decoupling capacitor mod

1. Solder wires to the capacitor

Start by soldering a black wire to the minus pin (the shorter pin) and then a red wire to the plus. Although not totally necessary I always also add a couple of shrink tubes to minimize the risk for shorts.

2. Solder the wires to the powerstrip

Locate the power strip. Solder the red wire to where it says VCC and the black wire to GND. Done!

 

Game Boy Decoupling capacitor mod

Final results

Before putting everything back together in the shell, make sure one last time that everything is working as it should. Put in a game and let it run for a while. When you are certain everything is OK, screw everything back together and enjoy your modded Game Boy.

I hope you enjoyed my modding guide. If you are having any problems or perhaps suggestions for things I could add to this guide, please let me know on my Facebook page.

 

Game Boy modded open

 

Game Boy DMG-01 modded yellow and cyan

August 18th, 2019|Blog, DIY, Gameboy, Modding, Retro|