For this instructable, I’m going to go over some of the basics to build a handheld N64  portable system.

Before you start this, you should have/learn the following skills:

• Basic to moderate level soldering skills. This means when I say you need to connect point “A” to point “B” you understand and have the soldering skills to do so. Soldering is not super difficult, so if you don’t know how, you could learn relatively quickly before you attempt this.
• General Case building skills. The more work you put into your case, the better it’s going to look. I have been doing stuff like this for a while, so I was able to make everything look fairly clean. This takes planning, and a steady hand with a Dremel, Xacto knife, Sand paper, and paint.

Parts you will need:

• An N64
• 3.8mm and 4.5mm Gamebit screwdrivers for taking apart your N64
• Batteries  (Li-poly, Nicad, etc. Whatever you prefer)
• Controller: Either 3^rd party or original. 3^rd party controllers have better joysticks in general, and are preferable.
• Screen: I used a 3.5 inch screen from ebay. Any screen will work as long as it will run off of 7.4 volts, and accepts composite input.
• Audio Amp: I used an HMDX audio amp. These can be found on ebay. You can use any audio amp you prefer though.
• Case: You can pretty much use anything as a case. My case is fairly small, you might want to start with a larger case so you can fit everything in more easily.

The first step is to disassemble your N64. I’m not going to go into a lot of detail on this, but it’s pretty simple. Use your 4.5mm Gamebit screwdriver to remove the screws from your N64. When this is done, you’ll need to remove the Phillips screws from the aluminum heat sinks on the N64. You will need to remove all the large aluminum heat sink material. Here’s a picture of what your N64 should look like when it’s removed from the casing and ready to start working on.

Now that you’ve removed your N64 motherboard from it’s casing, you’ll need to remove all of the ports and the Power switch. This includes the A/V out port, power port, controller ports, and the On/off switch. When that’s done you should have your N64 motherboard with only the cartridge slot, extension slot (the one on the bottom of the board, under the cartridge slot) and the expansion slot.

If you have room in your case, you can leave the Extension port on your N64, but to save room it’s best to remove it. The first step is but simply unplugging the cartridge slot from the top of the board. The cartridge slot should come out with little to not difficulty. When the cartridge slot has been unplugged, you have a couple options on how to remove the extension slot. I used a dremel and cut off wheel to cut it up and then rip it off with pliers. If you’re good at desoldering, you can remove it that way.

Once you’ve got your Extension port and Cartridge slot removed, you’ll need to reconnect your cartridge slot. You’ll have to solder a wire to each pin on the cartridge slot and then back to the corresponding solder pad on the N64. Make sure all your wires are the same length, and no longer than 3-4 inches long. If you wire the cartridge slot much further away from the N64 than this you could have problems.

Now for your case, the design will have to be whatever you come up with.  On mine, I cut the button guides from my controller and glued them into my case. You’ll also need to cut out a hole to mount your screen into. The screen I used came with a bezel, which I glued onto my case, so I didn’t have to worry about cutting my screen hole perfectly square.

Once you get your case ready, you can start gluing some of the electronics in. I started with the N64, then the buttons, then the screen, then the audio amp, then the batteries and voltage regulator. The N64 needs 2 different voltages, 3.3V and 7.4.v To get 3.3v you’ll need to step down 7.4 with a PTH08080was voltage regulator from Texas Instruments

You can purchase one here.

http://focus.ti.com/docs/prod/folders/print/pth08080w.html

It’s difficult to explain in text how to wire up this regulator, take a look at the diagram picture I have included.  You’ll need a 16v 100uf capacitor and a 2K resistor to wire it up.

For my portable I used lithium polymer batteries, which are more difficult to wire than Nicad or Nihm batteries, but they last longer and have a higher capacity.  I’m going to provide a couple diagrams on how to wire up Lipo batteries if that’s the route you choose to take.

These are the batteries I used:

http://www.batteryspace.com/Polymer-Li-Ion-Cell-3.7V-3900-mAh-684698-2C-14.43Wh-7.8A.aspx

Protection Circuit for these batteries:

http://www.batteryspace.com/pcbfor74vli-ionbatterypack8a-1alimit.aspx?SSAID=314743

Charger:

http://www.batteryspace.com/smartcharger12afor74vli-ionpolymerrechargeablebatterypack–ullisted.aspx?SSAID=314743

When wiring these batteries you’ll need to install a charge jack into your portable somewhere. Also, you’ll need to wire an on/off switch between the 7.4v line and the N64

Wiring the controller is fairly simple. There are 3 wires connect between an N64 and a controller. The red wire from the controller connects to 3.3v on the n64, the black wire connects to ground, and the white wire connects to Player 1 data. I have labeled these connections in the pictures.

Here’s some info on the HMDX audio amp I used. To wire up the volume control you’ll need to wire a button to the Volume + signal and Ground, and another button to the Volume – signal and ground. I’ve pretty much labeled all the information you’ll need in my diagram. You can use a couple 8ohm speakears from radioshack, or if you have room, just use the speakers the amp comes hooked up to.

You’ll need to wire your screen up too, unfortunately I don’t have any pictures of the screen internals, or diagrams. In general though, the 3.5 inch screens from ebay are relatively easy to work with. There are usually 3 or 4 connections on these screens

• Black wire will be ground
• Red wire will be voltage in. These screens run off of 7-12v
• Yellow will be your video input.
• If there is a 4th connection it’s usually another video input. You can just ignore this.

This is the screen I used. Search ebay and you should find it. There are a lot to choose from, which is why I didn’t include a link.

One last minor detail is heatsinks. The 3 biggest chips on the n64 will need heat sinks on them in order to stay cool. I used some copper ram heatsinks from ebay.

These to be exact:
Ebay Link

These heat sinks come in packs of 8. You will need at least 12. Four per chip.

That’s all the basic info. Everything beyond this is kind of trial and error, and case design decisions. This is all of my wiring diagrams and should get you off to a good start.

The following are the pictures I have of the internals, just to give you an idea of how I chose to install everything.

More pictures and worklog information

http://forums.modretro.com/viewtopic.php?f=33&t=5574

I know it’s been a while since my last update, but I’ve made a lot of progress!

Batteries all wired up to my 3.3v regulator.

Trimmed expansion pack, I am not relocating for this portable.

Test fitting before I install all the electronics…

I still need to decide on speaker placement and drill a few holes for those, also I need to decide on charge/play jack locations and drill holes for those as well. After all this is done I will need to start installing everything inside!

Z-button casing cut from N64 controllers and shaped to fit on the back of the portable.

Plano fishing lure box. This thing was the perfect size.

External 4 player controller port box, will also include A/V out in the back. I made this from the clear plastic casing my Ipod touch was packaged in. It has been painted transparent purple to match the rest of the system.

A, B, and C button pad.

Button Pads from Radica Tank-Assault game.

I’ve been working on this for a few weeks now. I’m still making my case, but it’s coming along well. I’m going to paint the whole thing transparent purple, thus the name Grape64.

I’m using a 3.5 inch ebay screen and an audio amp i picked up from kohls for 10 bucks. The case is a Plano brand case meant for fishing lures. I had to rip out the padding on the inside and scrub the glue off for a few hours, and then cover it in goo gone to get rid of the residue. The D-pad, Start button, and volume controls are all on a single board that I cannibalized from one of these Tank-Assault games, which I also snagged at goodwill.

The Nintendo logo on the screen bezel just by some random coincidence fits in there perfectly. I got that from one of the 10 broken GBA sps I keep lying around. I’m using the actual Z button section from two first party controllers as the R and Z/L buttons.