How to Make a Portable Game System

Ever thought about being able to play your favorite game system anywhere? I'm sure you have. Following this guide, you can learn how to 'portablize' the Nintendo Entertainment System.

In this Instructable I will teach you everything you need to know to put together a portable. There will be several different sections:

- What batteries to choose
- How to make a case
- How to wire everything
- What screen to get

These are just the basics. All these and much more will be discussed in this Instructable.

The console highlighted in this tutorial is the Nintendo Entertainment System. I chose it because it has tons of awesome games and it is easy to make handheld. The total cost of this project - for me at least - was $200. Now don't freak out - your price will be much lower. It was so high for me because I broke the first screen and NES. That set me back about 70$. :P You won't make the same mistakes, because you are going to learn from mine.

Now, this project is not for the lazy. It is not easy. It is not cheap. But the reward is worth so much more than what you spent, that you won't even care. :) My portable NES took me about 4 months to build, so lots of dedication is needed.

This Instructable will play with a new format; because the parts list is so huge, it would be ridiculous to post it all in one step. So, for each individual step, I will write the parts and tools needed for that one step. I will tell you one thing: get some IDE cable. That's the stuff that is used to connect hard drives inside of computers. IDE cable is invaluable to any portable. It's amazing stuff, and you will use it many times in this project. Get some in advance.

This project requires that you already have the basic knowledge to solder, use tools, simple stuff like that. This guide assumes, however, that you would have no clue where to start when building a portable. This tutorial is for you.

I urge you to read the following steps on picking and ordering a console, screen, and batteries. They contain very useful information and will help you greatly. It may seem like a lot to read, but please look at it all.

Now, let's finally get to the Instructable. :)

We will be covering the NES in this Instructable, but you can make a portable out of any console you want. Some are harder than others, though. Here are the "main" game systems that would be easy to make handheld:

Atari 2600
Nintendo Entertainment System
Super Nintendo Entertainment System

These systems are slightly harder:

Playstation One
Nintendo 64
Dreamcast

And these are VERY hard to portablize:

Playstation 2
Playstation 3
Wii
Xbox
Xbox 360
Gamecube

Obviously, the last list is only for people who are more comfortable with electronics and know their way around a PCB. For a first-time portablizer, I recommend the Nintendo Entertainment System. This console has tons of great games (SMB3, Kirby's Adventure, Legend of Zelda, and Mike Tyson's Punch Out, just to name a few.) and is a easy console to start with. The NES is what we'll be portablizing in this Instructable.

If you want to do a different console, then you need to look at http://forums.benheck.com/ . This is a huge community dedicated to making awesome handhelds, and it contains information on how to get power, video, etc. for your console, and how to cut down many systems to make them smaller. If you are going to do a console other than the NES - which is what we are going to work with in this Instructable - then you need to check out that site. Scroll down and find the forum for whatever system you want to do. Check the stickied topics in that section for all the information we have on that console. Also be sure to look at the Reference section.

Enough chit-chat. Let's get to the first step of portablizing!

Before we start ordering things, you must remember this: eBay is your friend. Just commit that to heart and you're all good.

For the most basic model of a portable NES, you will need:

- An NES (Hopefully you figured that out on your own.)
- A screen (We will discuss these later.)
- A battery pack (We will discuss this later.)
- A controller.

You could technically make an NES "portable" just by powering the console and a screen off of batteries. But that doesn't look good, and it's not really handheld. The above things are the bare essentials. But for a decently good portable, you will also need:

- A Dremel
- Stuff to make a new case (Acrylic, aluminum, etc.)
- Lots of wires

And more. We will discuss these things in the next steps.

If you already have the console you want to use, you don't have to buy one. If you don't, though, read on...

Old systems can easily be found in attics, closets, garages, and many other places. See if you can buy one for cheap from a friend. Try yard sales. You can always get stuff for cheap at those.

If you can't find an NES from any of the above sources, then you have to resort to eBay. Try to look for one with a case that's in bad shape. We will be taking the board out, so the condition of the case is not relevant. Also, try to find a seller that is in your country, so shipping will be low. Obviously, make sure the description says that the NES works, and check the member's feedback to make sure they are a reliable seller.

But what about those SuperHappyMegaJoy 72,000 in one things?
Glad you asked. The NES clones, or NOAC's (Nintendo On A Chip) could also be used for portables.
Here is one for $25: Link. It only takes 60-pin cartridges, though (Famicom), so you'll need to wire a 60 to 72 pin adapter (try some google searches, couldn't find a guide on this one). You could also try a Super Joy 3. They're good for NESp's, but also only take Famicom cartridges.

Most people use a PSone Screen. They are cheap compared to other screens, they are a nice size at 5.4", and they accept composite input without modification. If you are getting a PS1 screen, MAKE SURE you get the round-shaped one. Do not get the square ones; they are of horrible quality. If you are getting a PS1 screen, make sure your batteries are at least 7.5v. They can be above that, but you must perform an extra step if they are above 9v. That step will be discussed later.

Many other screens can be used. If you do not decide to get a PS1 screen, make sure the one you do get can accept composite input, and get one that runs under 12v, or picking out batteries will be very difficult. Many pocket TV screens can be used, like the Casio pocket screens.

Other good screens are as follows:
Hipgear/Intec Screenpad: 1.8", good quality. Runs on 5-12v. Here are pinouts and other info. Has audio amp. Find them at garage sales or possible eBay.
AEIComp Screens: 1.8" to 17". Expensive, but great quality. Here is a guide to making it smaller and where to attach video. No built-in audio amp. Takes 5-12v.
DealExtreme Screens: 2.5", 3", and 3.5". Good quality, cheapish. Here is a guide for the 2.5" one. All take 7.5-12v.
Casio EV-680: Good quality, takes 5-6v. Hacking Information. Look on eBay for these, or maybe garage sales. Other Casio TV's are good, as well.

Before we discuss where to get batteries, you need to think about what kind of batteries you want. There are two main kinds; NiMH and Li-ion.

NiMH batteries are the kind you see that power RC cars. They come in battery packs, and need no special circuitry to charge them. They are very heavy.

Li-ion batteries are very common. They power laptops, portable DVD players, cell phones, etc. They are very lightweight and have lots of mAh, meaning that they can power a portable for a very long time. They require special circuits to charge them.

Conventional batteries are what you use for all sorts of electronics. These batteries are your standard AA, AAA, 9v, D, and C batteries. These are relatively cheap, but they aren't rechargeable. (Unless, of course, you buy rechargable ones.) Conventional batteries can get expensive over time, and they are a little heavier than other types of batteries.

As you can see, all types have their pros and cons. For NiMH and Li-ion types, there is a rule.

You can get batteries that are:
- Cheap
- Lightweight
- Long-lasting
Pick two.

If you want to choose NiMH, then you don't have to do much for them. They are cheap, and to charge them, you just feed power straight to them. Dead simple. Unfortunately, they are often heavy and big.

Li-ion batteries are great, but require a bit of work. They need special charge protection circuits. They cannot be shorted or overheated. Despite these things, they are very worthwhile. They are small, thin, lightweight, and long-lasting. The bad part is that they cost quite a bit.

WARNING: If you do not have a charge protection circuit, Li-ion batteries will EXPLODE. These batteries are dangerous if not used properly. They may not be shorted, overcharged, or undercharged. If you are buying Li-ion batteries from eBay, you MUST buy a Universal Battery pack. These battery packs have their own built-in charge protection circuits and often have charge indicator LEDs. If you do not know much about Li-ion batteries and their various protection circuits, then you MUST use NiCD.

Conventional batteries are great for the "average joe." They are readily available and are easy to use. But, unless you get rechargeable ones, these can cost quite a bit in the long run. The good thing is that these batteries come in many shapes and sizes to suit your needs. If you're going with conventional batteries (Like AAA's, AA's, C's, or D's), then you need to pick between battery life and weight. AAA's will be very light, but have a short battery life. D's will give you many hours of playtime, but they are extremely heavy. AA's and C's are in between.

There is one more important factor: mAh. mAh stands for Milli amp-hours. The mAh of a battery is how many mA that battery can provide for an hour. If a console and screen that together consume 1,000mA is being powered by a 1,000mAh battery, then that portable would run for 1 hour. Find batteries that have a high mAh. Batteries with 3,500 will run an NES portable for about 3 hours.
To find battery life, add the mA consumption of the console to the mA consumption of the screen. Divide that number into the mAh of your batteries. This may all sound confusing now, but the more you work with the batteries, the more it makes sense.

Here is a useful topic that has the mA consumption of many consoles and battery life estimates for them.

Now we can finally get started on this thing.

Many people have trouble when building a portable because of wires that are too thin. If your wires are too thin, they won't be able to pass enough current, and things won't turn on.

For signals and low-power applications, IDE cable works great. It's 28 AWG and can be found in many old computers. It shouldn't be used for high-current situations.

For most power lines, you should use at least 20 AWG.

You can find all kinds of wire at your local RadioShack.

To be sure everything works, you should hook everything up without modifying anything. Below is a picture of my setup. The battery is connected with alligator clips. This step is mainly to be sure all your stuff works fine, and that the battery can handle the mA draw.

If your batteries are more then 8.5v, then you MUST go and do step 17 before hooking your screen to your batteries. You will fry your screen if you don't!

What you need:
Phillips screwdriver
NES

Once everything is assured to be working, you need to take apart the system. The NES is very easy to take apart. All you need is a phillips screwdriver.

Flip the NES over and remove the 6 screws on the bottom and the 2 for the controller ports.

Flip it back over, remove the top, and take out the 5 screws holding the shielding in.

Take the shielding off, and unscrew the 6 screws holding the cartridge mechanism in.

Remove the cartridge mechanism (you may have to slide it forward a bit) and take out the 2 screws near the RF box in the upper right corner.

Unplug the two player ports and the power/reset plug.

Pull out the NES board.

Congratulations! You now have your NES taken apart. If you want, test it to make sure it all works fine.

What you need:
Pliers
Soldering Iron
Desoldering Iron

The RF box takes the composite signal from the NES and turns it into RF. It also takes the 9v from the external adapter and turns it into 5v. It is much too big, so we are going to take it off. If you hook up power, then you will notice that the NES does not respond to the power button; it is just constantly on. That is normal, so don't worry.

DESOLDERING
Start by desoldering the four tabs. Obviously, you won't be able to fit your desoldering iron over the whole thing, so you have to suck up as much solder as you can from the sides of the tabs.

Desolder the 5 pins.

Flip the NES board over and take off the cover of the RF box.

Find the regulator and desolder it. The regulator looks like a small black box with 3 pins and a metal tab at the top. We need the regulator to bring down the voltage of the batteries so it is safe for the NES board.

TAKING OUT THE BOARD
The RF board will be soldered to the metal walls in several points. Take your pliers and break the walls away from the board. Do not worry about hurting it, we won't be needing it.

Grab your pliers and start breaking off pieces of the board. We want to take it all out so it is like picture 3.

Bend the walls until they break off the board. Using your soldering iron, take out the pins, if there are any left still in. Grab the part that is sticking out and pull, while heating the other end with your soldering iron.

You should now have all parts of the RF box taken off. Make sure you save the 7805 regulator and the heatsink that is attached to it.

Steps 9 through 11 are optional. They are to make the NES thinner, if space is tight in your case.

What you need:
Desoldering Iron
Soldering Iron
IDE Cable

There are a lot of capacitors sticking up on the board. These need to be flattened. All the ceramic capacitors (The brown disks) can just be bent over. The electrolyic capacitors (The cylindrical ones that look like cans) cannot be, so we must relocate them.

Relocating capacitors is an easy task, but can be quite boring. Luckily, the NES only has 3.
This is really easy to do. The second picture explains everything.

First desolder the capacitors.

Get some small pieces of IDE cable and strip the ends.

Solder them to the capacitors, then to the NES board. Make sure you get the polarity right, or your NES will not work.

Use a small dab of hot glue to hold them on the board.

You can do this operation for any system with large capacitors. It is almost essential if you want a decently thin portable.

What you need:
Small flathead screwdriver
Needle-nosed pliers

The NES has a useless expansion slot on the bottom of it. This was never developed further, and serves no purpose on our board. Time to take it off.

Find the expansion slot. If you need help with this, then you probably shouldn't be attempting this project.

Find the four metal tabs on the side of the slot. Bend them out with a small flathead screwdriver.

Bend the metal shielding away from the plastic and remove it.

Snap off the outer layers of plastic with your needle-nosed pliers, being careful not to harm the NES board.

Grab the metal pins and the plastic with your pliers and snap the plastic off.

Bend the metal pins until they snap off.

Take the small flathead screwdriver and use it to pry up the remaining plastic and reveal the pins underneath.

Bend those pins until they snap off, and you are finished!

This makes the NES board much thinner, meaning a thinner portable.

What you need:
Desoldering Iron

If there are any more big things that can be removed, then do so. In the case of the NES, the largest remaining part on the board that we can remove is the power/reset plug. This is an easy step, simply desolder the connector. On other systems, there may be other things that need to be removed, like controller ports, power plugs, video plugs, etc. Remove those things to make the board as small as possible.

What you need:
72 pin 0.1" Spacing Card-Edge Connector
Soldering Iron

If you want to keep the original cartridge connector, you may do so. I decided to use a new one, to make the portable thinner. You need to get a connector that has 72 pins and 0.1" spacing. Here is a suitable connector, and here is one with cheaper shipping.

Take the connector and press the pins close together so that they grip the NES board when you slide it on.

Simply, start soldering. This doesn't take long. Apply iron. Add solder. Repeat.

The soldered connector is very strong, and shouldn't need any support.

What You Need:
Soldering Iron
Lots of wire
Wire stripper
72 pin connector (link in previous step)
Plenty of patience

If you want to put the cartridge connector somewhere other that at the top of the NES board, you need to do what is called "relocating" it. This is where you extend the slot by soldering wires to all the connections on the NES and to the cartridge slot.

You need 72 wires (IDE cable works great for relocations) for this. Strip both ends of all the wires and tin them. Tin the contacts on the NES board and on the connector.

Then, start soldering the wires to the NES and to the connector. Simply make sure you correspond the right contacts. Just look at the soldered connector in the previous step and pretend to pull it away from the board. Make sure you double check your wires when you're don't and make sure they're no longer that 6 inches.

What you need:
2N4401 Amplifying Transistor
33ohm Resistor (Orange-Orange-Black-Gold)
220ohm Resistor (Red-Red-Brown-Gold)
Soldering Iron

The RF box did more than just turn the composite to RF. It also amplified the video signal. When we took it off, the video signal became weak. We need to build a small video amp to boost the signal.
The second picture explains it all.

SOLDERING THE AMP TOGETHER
Solder one end of the 33ohm resistor to the emitter of the transistor.

Solder the 220ohm resistor to the other end of the 33ohm resistor. That point is your video out. We will connect that to the screen later.

SOLDERING THE AMP TO THE NES
The amp is finished. Clip the leads on the transistor, then solder the base of the transistor to the weak video signal, and the collector to 5v.

All this may sound a little confusing, but pictures 2 and 3 explain it all. Picture 4 has the schematic, if you prefer.

I soldered the resistor leads very close to the transistor, but you may not wish to do this. If you heat the transistor up too much, then it won't work anymore. Feel free to make the circuit on a small piece of perfboard.

This is an optional step, you may skip it if you like.

What you need:
Soldering Iron
Small screwdriver
Piece of wire

The lockout chip in the NES was included to prevent pirated games from running in the console. It is also the reason that you get the blinking screen. If the console's lockout chip and the cartridge's lockout chip don't communicate, then the game won't play. Half the time, it's not because of dirty contacts. The games would run fine if it weren't for the lockout chips. Disabling it means a much higher success rate.

PULLING UP PIN 4
To disable the lockout chip on the NES, first locate the actual chip. It is close to where we soldered the video amp, and it is labeled 3193A.

You need to pull up pin 4 of the lockout chip. Taking the whole chip out won't work, because it is connected to the reset line, and the console won't run without it. Instead, find pin 4 of the chip. The first picture shows pin 4. Put the small screwdriver under the pin to kind of pull it out of the hole. At the same time, heat the lead from the other side of the board with your soldering iron. Pull the pin out so it's not connected to the board.

GROUNDING THE PIN
You could be done right there. The lockout chip is disabled right now, but it is still a good idea to connect the pin to ground. Take your piece of wire and solder one end to the pin you pulled up, and the other end to the silver grounding strip going all around the board.

All your games should now run very well. The NES board is now complete. Next we'll build the power supply for it and test it out!

What you need:
Soldering Iron
Medium-sized piece of perfboard
7805 Regulator (From the RF box)
Heatsink (You can use the one from the RF box if you like)
1,000uf Capacitor
Two 0.1uf Capacitors
1 - 10uf Capacitor
1N4001 Diode

Before we start, you have to understand what a regulator is and what it does. A regulator takes any voltage above a certain amount and drops it to a specified voltage. For example, the 7805 regulator we are using takes anything from 7.5 - 36 volts and drops it to 5v, which is what we need for the NES. The extra energy is given off as heat, so you need something called a heatsink. A heatsink attaches to the regulator and dissipates the heat coming from it. Without a heatsink, the regulator would burn itself out. The more surface area a heatsink has, the better it takes heat away from the regulator. You can use the one from the RF box.
Note: A 7805 needs at least 7.5v to run, so you must make sure your batteries are at least that much.

SOLDERING THE BOARD
Anyways, the schematic for the regulator is in the first picture. It has a drawing of the regulator and its pins. Pin 1 is the voltage in, pin 3 is ground, and pin 2 is five volts out.

The reason for all the capacitors is to smooth out any ripples in the voltage coming from the batteries. C1 can be anything from 250uf to 1,000uf, and smooths the voltage coming straight from the battery. I just used what I had lying around, which was a 250uf cap. C2, C3, and C4 smooth out the current coming from the regulator.

Some capacitors can probably be excluded, like C1 (1,000uF) and C4 (.1uF). Also, C1 could be around 470uF as well. The values aren't all that critical.

OPTIONAL
The diode, D1, is not necessary. It is only there to drop the voltage by about 1v, because I found that the regulator really gave out 6v. The NES will be fine running at 6v, but I just wanted to be safe.

I used a 3-pin connector for my regulator board, because I wanted it to be removable.You don't have to, but it does make things easier.

See above note about capacitors.

TESTING THE BOARD
You can finally test your NES! Solder the output pin on your regulator (+5v out) to the 5v in on the NES, and attach ground. Use a couple of alligator clips to hook it up to a TV. Plug in a cartridge (Make sure it's facing the right way!), add the battery, and try it out! If it doesn't work, don't worry. Try switching the alligator clips for video and ground. If it still doesn't work, check all your connections. Make sure there are no shorts anywhere. It is highly unlikely you fried your NES. Once you get it working, set it aside and get out the screen you ordered.

What you need:
Small flathead screwdriver
Small phillips screwdriver

READ THIS PLEASE!! The PS1 screen takes a max of 9v, and that's still pushing it a little. If your batteries are more than 9v, DO NOT hook up the screen. You will fry it! Please complete the next step and then come back to this one.

With the NES finally done, it's time to start work on the screen, beginning with disassembling it.

TAKING THE CASE APART
There are 9 screws you need to take out. Unscrew the three visible ones on the bottom.

There are two rubber plugs at the top of the screen. Pry those up and remove the screws beneath them.

Lift up the speaker covers and take out the four screws hiding underneath.

Flip the screen over and take off the back cover. You can test the screen now if you wish. BE CAREFUL NOT TO TOUCH THE TRANSFORMER AT THE TOP! It's the little white rectangle with copper wire wrapped around it. A very high voltage comes out of it, so be careful not to touch anything in that top section. You'll be fine when the screen isn't plugged in, though.

TAKING OUT THE SCREEN
There are 4 screws sort of in the "corners" of the board. Unscrew those.

Snap the speakers out, and gently flip the screen over onto your hand; set it down.

You can test it again now if you want. Make sure the metal around the screen is touching the contacts underneath the tabs.

What you need:
Soldering Iron
7805 Regulator
470ohm Resistor
220ohm Resistor

Don't hook up the screen just yet - we need to build a small regulator for the screen.

It's very simple, just follow the diagram below.

You can use a 7805 to get 8v, or you can use a 7808. A 7808 is just like a 7805, but it gives out 8v instead. Using a 7805 is much more convenient in my opinion, because you can easily find them in old electronics. If you want to know how this works, then check the last paragraph.

The PS1 screen can handle from 6.89v to 8.5v. Preferably, it should get 7.5v, but as long as you have a decent 7805, you'll get the voltage you need. As always, test the output voltage before hooking it up!

BUILDING THE REGULATOR
To build the regulator, just solder the 220ohm resistor to the ground (middle) pin of the regulator. That will be your ground, which you must connect to the screen's ground, too.

Solder the 470ohm resistor to the ground pin of the regulator BEFORE the other resistor. Solder the other end to the output pin, and that is your 8v out, which you will connect to the blue wire of the screen in the next step.

Just like the NES's regulator, it's a good idea to put a small heatsink on this one, too.

Solder the negative lead of your batteries to the ground spot on the regulator. In a couple steps, you will solder the 8v out connection to your screen. For now, just leave the V+ input and 8v out wires disconnected.

HOW IT WORKS
This works because it is essentially a LM317T regulator, but with a higher output voltage. The LM317T is an adjustable voltage regulator. It can output anything from 1.5 to 12v with a 15v input source. All you need is two resistors. You hook them up in the same way as below, except you would choose different resistor values for different voltages. So why does the 7805 work for this purpose? Because the LM317T is simply a fixed 1.25v regulator. Experimenters rarely use anything below 5v, so a 7805 can do the job as well.

What you need:
Hot glue gun
Soldering Iron
IDE Cable or other wire

Once you have unscrewed the screen and tested it, you need to add the audio and video wires.

Unplug the two connectors at the bottom. You only need to keep the left one. We'll use that for power later.

SOLDERING THE A/V WIRES
Flip the screen to the back and find the small pads near the bottom-left that say EXT_V, EXT_R, EXT_L, HP_L, HPS, and HP_R. EXT_V is where you solder the video wire, EXT_R is right audio, and EXT_L is left audio. For the NES, you can short the L and R on the screen, because the NES is mono.

SHORTING THE HEADPHONE WIRES
If you tried to test it at this point, you would notice that there is no sound. You need to short together HP_L, HPS, and HP_R. Otherwise, the screen thinks headphones are plugged in. If you want headphones on your portable, do not short those three pads and use the headphone jack that was included with the screen.

Once you soldered the wires, put some hot glue on them so they don't come loose.

What you need:
Wire cutters
Soldering Iron
Heat shrink tubing
Heat gun or some heat source for heat shrink tubing
IDE cable or other suitable wire

WIRING POWER
Take the connector you saved and find the two wires all the way to the left. Those are your power wires. The blue one is positive. Chop off the rest of the wires and solder a red wire to the blue one and a black one to the white one. To test the screen, simply attach the red wire to the positive end of your power supply and the black one to the negative side of your batteries. The screen's light should turn on. If not, see the last paragraph. You may have switched your connections and blown a fuse.

ATTACH THE REGULATOR
If you had to build the regulator for the screen, don't attach power just yet. Solder the 8v out wire from the regulator to the red wire of your screen. Solder the black wire to the ground spot of your batteries, which should also be connected to the ground on the regulator. Touch the positive wire from your batteries to the V+ in on your regulator, and the screen should light up. If not, check the last paragraph in this step.

A/V ON THE NES
Once you are sure the screen works fine, solder the audio and video wires to the appropriate spots on your NES board. The audio wire just gets soldered straight to the pad on the NES board, but the video wire has to be attached to the amplifier we built. Solder it to the video out wire on the amp. See the picture if you need help.

CHECKLIST
Before turning everything on, do a couple checks first.
Are the console's ground and the screen's ground tied together? They must be, or nothing will work. The screen and the console must share a common ground.
Is the NES's regulator board working? Is it connected to the NES?
Is the screen's regulator working, and is it connected to the screen?
Are the screen's power wires reversed? Make sure they are not.
Are audio and video wires soldered to the correct spots?

Once you are sure of these things, go ahead and put in a cartridge (Make sure it is facing the right way! If you used the connector I did, the label should be facing up, and so should all the NES's electronics.) and attach the power wires of your batteries. The screen should turn on, and so should the NES. You should get a nice picture on the screen. If everything is not working, check the troubleshooting list below.

TROUBLESHOOTING
Troubleshooting: If it does not work
Does the video amp work? You may have fried the transistor while soldering to it.
Did you reverse the screen's power connections? You may have fried a fuse.
Do the screen and console share a common ground?
Are the batteries charged?
Can your batteries handle the amp draw? Anything better than AAAs should work.
Are any wires touching that shouldn't be?
If you are using Li-ions with a protection circuit, and there was a short, unplug the Li-ions from the protection circuit, then plug them back in. If there was a short, then the protection circuit switches off the batteries.

Check everything and find the problem. If it still doesn't work, you may have fried something.
First check the regulators. Are they putting out the voltage that they need to? If they are, but the voltage drops to almost zero when you add a load, then try replacing the 7805.
Does the screen light up when you add power? If not, see the last paragraph.
If the screen does light up, but you get no picture, then try using a different video input. If it works then, try building a new video amp for the NES. If the screen does not work after trying a different input, check the next paragraph.
If the new video amp does not work, your NES is dead. Get a new one, and be more careful with it.

IF YOUR SCREEN DOES NOT POWER ON
What to do if your screen does not work:
There is a fuse on the PS1 screen. If you reverse the power to the screen, then this fuse will blow, and the screen will appear to be dead. Not to worry - if you jump this fuse, the screen should work again. On the front of your screen, down by the connectors, there is a small rectangular object that has the word PS1 printed next to it. Put your soldering iron on one end of it and kind of "pull" it away from its pads with the soldering iron, so that the fuse is removed and there are just two small solder pads. Add a blob of solder right there, so that the two solder pads are bridged. Viola! The screen should now be working. If not, it is most likely dead. Sorry. :(

What you need:
Small flathead screwdriver
Hot glue gun
Soldering Iron
IDE cable or other suitable wire
3mm LEDs
Sandpaper or something to diffuse the LEDs
20ohm resistor
Electrical tape
X-Acto knife

WHY YOU SHOULD DO THE LED MOD
LED modding the screen is when you replace the original backlight with LEDs. Why would you want to do this? The unmodified PSone screen draws about 950mA. If you LED mod it, it only draws 450mA! That's a huge difference! In some cases, this can add add hours of playtime to your portable.
On my portable, the current draw is about 1150mA with an LED modded screen. I get 3 hours of play with my 3500mAh battery. If I didn't mod my screen, the entire portable would draw 1650mA. Dividing that into the battery's mAh, you get 2.1 hours. By modding my screen, I gained a whole hour of playing time!
"What's the catch?", you ask. Well, it's a small one. The corners are bright spots, but that's it. It's hardly noticable when you are playing. If you use 8 LEDs you can simulate the original backlight in terms of brightness. If you only use 3, like I did, the screen isn't quite as bright as the original backlight, but it still looks very acceptable. I think the best option is to use 6 LEDs, because it is about 95% of the original brightness, and it isn't as much work as 8.

Enough chit-chat, here's the actual procedure:

TAKING OUT THE SCREEN
Flip your screen over to the backside. Find the screen ribbon connector on the lower-left.

Using the flathead screwdriver, carefully pop up both sides of the connector.

Turn the screen back over and find the plug in the upper-left corner with the white and pink wires coming out of it. This is the CCFL (light tube) connector. Unplug it to free the screen.

Carefully lift the whole screen section away from the motherboard. Watch out for the tab on the screen's ribbon connector.

Picture 4 shows the entire screen section, removed from the main board.

TAKE OUT THE LCD
Now we need to take off the metal surround. Find the rectangular holes in the metal with the white plastic showing through. Use the flathead screwdriver to pry up this part, so the metal is not held in by the plastic tabs. There are tabs on all sides, so make sure you get them all.

Once you are sure you've freed the metal surround, carefully lift it away from the rest. Put it aside for now.

You now have the screen in three pieces. The metal surround, the light box - which we will work on in a moment here - and the LCD. Find a soft cloth and wrap the LCD in it, and put that in a very safe place. You don't want anybody touching it. Make sure you handle the LCD only by the sides. If you want to do the antiglare mod, head to step 22 before putting the screen back together later.

TAKING APART THE LIGHT BOX
The white box-like thing with the connector coming out of it is the "light box". This light box has 5 things inside: two pieces of diffusing plastic, one piece of diffusing glass, a thin "U" shaped tube, and a piece of glossy paper. Make sure you don't touch the glass or plastic; you don't want fingerprints on them.

Find the tabs on this light box and pry them up the same way you did with the metal piece. It's much easier here, because it's plastic instead of metal.

Open up the light box. It has a sticker on the bottom, so it's hinged. Carefully remove the piece of glass and the two pieces of plastic. Make sure you keep them in the right orientation, meaning, don't flip them upside down! It will make the screen dimmer, and if you flip the glass, than you'll have a bunch of white dots on the screen's picture when you're done. (I learned this the hard way.) When picking up the glass and plastic, only touch the edges. Set the glass and plastic in a soft cloth just like the screen and put them somewhere safe. Now take out the glossy piece of paper and put it with the other screen items.

TAKE OUT THE ORIGINAL LIGHT
Carefully remove the CCFL from the plastic. Be careful not to break it, because it has mercury, which can kill you if you breathe it. Keep the tube, in case you decide not to do the LED mod.

INSTALLING THE LEDS
Now we can start the actual procedure. Take 3 LEDs (Or however many you will be using) and diffuse them. You are using 3mm LEDs, right? Any other size won't fit in the light box. Trust me, I've tried. You can get the LEDs from eBay, like I did. I got 100 of them for only $15 shipped. Very cheap! Buying just ONE 5mm LED from Radioshack costs $5! And the brightness is only about 3,000mcd! My LEDs are 14,000mcd and I got a HUNDRED! Best to buy in bulk. ;)

Anyway, back on topic. After you diffused your LEDs, cut out a very small piece of the corner of the plastic light box. It only needs to be big enough for the LED's leads to go through.

Put the LED facing in with the leads going through the slot. Use a VERY small amount of hot glue to hold it in. If you put too much, things won't work out right later. Check picture 14 to see the orientation that I put my LEDs in.

After you do all three LEDs, it's time to put the light box back together. Put the piece of glossy paper back in first. You'll need to cut it a bit to let the LEDs fit. Put the glass in next, then the two pieces of plastic. Make sure the tabs on the left side of the plastic correspond with the pegs on the plastic. Fold the top piece back over, and snap all the tabs back together. If it doesn't want to go easily, open it back up and make sure you didn't use too much hot glue.

PUT THE SCREEN BACK TOGETHER
With the light box closed, I tested the LEDs with the screen placed on top. Looks good to me! Carefully place the metal surround back on, and snap it onto the light box. Be very careful when doing this, if you chip off a corner of the screen's glass, it will no longer work.

Your screen should now be complete! All's that's left to do is solder together the LEDs and attach a resistor.

SOLDER THE LEDS
You want to solder the LEDs in parallel. Get some pieces of ribbon cable, and solder together the three LEDs positives together, then solder the three negatives together. Solder the end of the negative wire to the ground spot just to the left of the screen.

Take your resistor and clip the leads really short, just a couple millimeters long each. I originally used a 10ohm resistor, but that turned out to be too small of a value, because I had 2 LEDs burn out from it. It is best to use 20ohm for these LEDs.
Solder one end of the resistor to the positive wire of the LEDs. Solder a wire to the other end. Put the wire through the hole in the board right below the screen. To the side of that hole is a black, blocky-looking component. This is a mini-7805. Solder the wire to the 5v out, which is the leftmost pin.

Put a piece of electrical tape down on the front of the board, just below the screen.

Hot glue your resistor to that piece of tape.

TEST THE BACKLIGHT
The wiring is done! Plug the screen into it's connector on the bottom of the board, making sure it goes all the way in. Press the connector down to secure the cable, and hook up power! If the LEDs light up, great! If not, check all your wiring. Once the LED backlight is working, turn on the NES. A picture should show up on your screen! Great job! You now have the console, battery, and screen section of your portable done! You may notice that the screen is a little dimmer with 3 LEDs, a small consequence of doing the LED mod. See the next step for a fix, where you can do the "brightness mod". See the step after that for instructions on how to remove the anti-glare layer on your screen, which removes the scratches, makes the screen brighter, and makes the colors look better.

What you need:
A small piece of wire
Soldering Iron

This is for if you did the LED mod and noticed the screen isn't very bright. There is an easy fix to this, but the contrast is slightly affected.

Turn the PSone screen board over. Find the chip in the very middle surrounded by a bunch of small surface mount components. Find the one that is called "CV23". This is the brightness control.

What we want to do is jump that component. You could remove it and put a piece of solder in it's place, but it's better to jump it; in case it is too bright for you, you can just undo it.

Simply take a small section of wire with the ends stripped, and solder one end to the bottom side of CV23 and the other side to the top of it, so that it essentially isn't there. Enjoy your brighter screen!

This Step Is Optional

What you need:
Paper Towels
Water
X-Acto Knife
Patience

This is where you can remove what is called the "antiglare" layer on the PSone screen. This layer is a thin, diffused piece of plastic. It is used to keep the screen from reflecting a lot of light. Removing it takes off any scratches, and makes the colors more vibrant and the screen brighter. Since I did not do this mod myself, I have no pics to explain this procedure with. Instead, here are pictures and documentation from another person. These are courtesy of Hailrazer of the benheck.com forums. The pictures have captions on them with the steps embedded.

Quoted directly from Hailrazer's topic (Link here):

"Some of you may know this already but I thought I'd pass this on to any who might like to know.

If you're like me sometimes while working on the Psone screen you might scratch it up or smudge it a bit. Also you might notice that it's a bit murky looking. Like this :

(Picture 1)

Well on the top of the Lcd is a Antiglare layer. It is a protective layer that is on top of the Lcd that also serves the purpose of reducing glare. But it has the side effect of muting colors and reducing brightness. The solution. TAKE IT OFF !!

The easiest way to do this is called the "Water Soak" method.

Here's what you do. Starting with the Ps1 screen stripped down to this:

(Picture 2)

1. Remove the metal bracket holding the Lcd to the backlight. Ben has a tutorial on this already so I'll spare you the details. (Note : This can be done without removing the metal bracket, it just will take more effort later)

2. Remove the Lcd from the backlight (by just lifting it off) and set it on a towel or similar surface. The pic shows leaving it on the backlight but I have changed this. If you take the Lcd off the backlight then you don't have to wait as long to allow the backlight to dry after performing the mod.

(Picture 3)

3. Take a couple of paper towels and layer them in 3-4 layers. Cut the paper towels where they cover the LCD precisely and lay them on the Lcd.

4. Wet the paper towels by dripping water on them slowly. You want enough water on them for the paper towels to be soaked, but not so much that the water is dripping over the edges into the backlight. The paper towels can hang over the top edge but DO NOT let them hang over the bottom edge. You don't want the ffc's getting wet for a long time. Also try to get most of the bubbles smoothed out of the paper towels. You want the wet paper towels to make a good contact with the Lcd.

(Picture 4)

5. Leave paper towels soaking for 4 hours. I repeat 4 hours. Do not soak for less than 4 hours. You want the antiglare to come up in one piece without any sticking or glue residue so it is imperative you wait for 4 hours.

6. Remove paper towels.

7. On top of the Lcd you will notice a thin layer that is covering it. This is the polarizer/Antiglare layer. The polarizer is on top of the Lcd and it is the thicker layer with a tinted look. the antiglare layer is on top of it. It is paper thin and is clear/slightly cloudy. We are going to use the razor and pick at the edge of this dual layer. The antiglare layer will be very thin and will look like a piece of clear but slightly cloudy saran wrap. It will peel off very easily. If the piece you are pulling up is tinted and stiff STOP, you are pulling up the polarizer layer and this will render the screen useless. Once you get the edge of the antiglare up , pull it off slowly in one motion. After the antiglare is removed you can wipe off the excess water with a lint free cloth like an eyeglass cleaning cloth.

(Picture 5)

This is what the removed Antiglare looks like :

(Picture 6)

8. After removing the antiglare there is nothing else to do but make sure the Lcd is totally dry and water free , remember water+electronics=BAD. Re-assemble and reconnect the panel after it is dry and enjoy a scratch-free screen with better brightness and colors.

(Picture 7)

And here's a pic of before and after. It's hard to tell the differences when not holding it in your hands. But there is less of a dull look , colors are more vibrant, and better focus.

(Picture 8)

Also like I said if you accidentally scratch or scuff your screen , this mod will fix that. :)"

What you need:
Perfboard
Eight 47k Resistors
Eight Tact switches (See 2nd and 4th paragraphs)
4 NES controller A/B buttons
NES controller D-Pad
4021 Shift Register
16-pin DIP Socket
IDE cable (or other suitable wire)
Hot glue gun
Soldering Iron
Desoldering Iron
NES Controller Plug (From NES case)
Small Screw
NES Controller Cable

HOW YOU SHOULD BUILD THE CONTROLLER
Once you have everything working, you need to build the controller for the NES. There are two ways you could go with this; building your own or using the original controller boards. There are pros and cons for both:

Building your own is fun and helps you learn more about electronics. If you build your own, it is easier to mount in the case. The only problem is that if you use "clicky" tact switches, then the controller does not feel like the real thing.

You can use the original controller board. This is a great option because it feels like an original controller, and it is a lot easier to put together than the first option. These are often difficult to mount in a case. If you want to do this, check the next step for a bit of information.

OR, you can meet at the middle and combine method 1 and method 2. Make your own controller (easy to mount) and use these "mushy" tact switches from Mouser (feels like the original controller). This is the best option, in my opinion. Unfortunately, I did not find these switches until after I completed my portable, so that's too bad. Next time...

For my first portable I went with option 1. I wanted to be able to really feel that the switches are actually being pressed. If you want to do option 2, check the next step. For 3, just use option 1 but with the squishy switches.

HOW THE CONTROLLER WORKS
It's nice to understand a bit how the controller works. If you don't think so, just skip this paragraph.
The NES controller uses something called a shift register. This basically takes your button presses and converts them into signals. Once they reach the NES, the NES looks at them and figures out which buttons are being pressed, then changes the game accordingly. That's how the NES controller can have 8 buttons and only use 5 pins.
You also need to know that the shift register in the NES controller uses "pull-up resistors". These are resistors that connect each of the data pins to a small voltage, so that each pin is in a "high" state. To send the signal, the register pulls the pin "low".
Now, aren't you glad you understand that? Building the controller will be so much more fun now. :)

Since it would be ridiculous for me to write out every single wire that you need to connect, I will have to give you a schematic instead. It is the second-to-last picture in this step. I can still give you the general steps and some tips, though:

GENERAL STEPS
Take apart the NES controller. Hopefully you can do this on your own.

Desolder the 4021 shift register chip from the controller. Be careful not to overheat it!

Cut a piece of perfboard using an X-Acto knife and pliers. Score the perfboard many times where you want the board to come apart. Take your pliers and grab right next to the score line, then bend the perfboard to snap it off.

Lay out all your pieces on the perfboard and find a configuration that is functional. Try to make it so that the resistors are close to the tact switches, something I failed to do on the d-pad half.

Solder all your pieces in. Make sure you use the 8-pin DIP connector. Don't directly solder the chip in, or you risk burning it out.

Start building the circuit shown in the schematic. One side of the tact switch is connected to ground, the other side is connected to the correct pin on the 4021. Each of those lines has a resistor connected to it, the other end going to +5v.

TESTING THE CONTROLLER
Once you get the d-pad half done, you might want to test it out. The Red, Orange, Yellow, White, and Brown are referring to the colors inside the NES controller's cable. Just strip and solder the wires to the correct points, as shown on the schematic. One important thing to note is that BOTH pins labeled BROWN on the schematic must be connected. You cannot connect only one, or it will not work. Trust me, I made that mistake. It was very frustrating figuring out why my controller did not work.

Pop in the chip, making sure it is facing the right way. For me, it was the notch facing the tact switches. Plug it in to your NES system, and test it out. Once you confirm that it works, continue on and build the A/B and Start/Select board.

BUILD THE OTHER HALF
Use the same procedure for the A/B Start/Select buttons with another piece of perfboard. Connect the two boards with a piece of perfboard. Again, one side of the tacts must go to ground, and the other side must go to the pins on the 4021, each with a pull-up resistor. The last picture shows the pinout of the 4021, and where to connect the button wires.

ATTACHING THE CONTROLLER PLUG
Once you finish the controller, take one of the sets of wires that connected the controller ports inside the NES and cut it off from the connector port. Solder it to the controller. Again, the colors match those shown in the schematic. You now have finished the controller!

What you need:
Soldering Iron
Needle-Nose Pliers
X-Acto Knife

To use the original controller boards, you need to cut off the board sections, then solder wires to them.

You need to cut off the A/B buttons section, the Start/Select section, and the D-Pad section.

Using your X-Acto knife, score the spots shown in the picture.

Use your needle-nosed pliers to break off each section of the boards.

Scrape the light green traces off so you can see the copper underneath. Solder your wires to these. You basically want to extend the controller board sections.

What you need:
Hot glue gun
Some kind of light foam (optional)
4 NES controller A/B buttons
An NES controller D-Pad cross
Plastic card (A gift card works well)
X-Acto knife
A file

With the controller done, you need to make the buttons. For the A, B, Start, and Select buttons you will need 4 NES controller A/B buttons. You are free to use whatever buttons you like, these are just what I wanted to use.

TAKE OFF THE OLD TABS
To start, the tabs on the buttons were too thick. I had planned ahead what thickness of plastic I would use (1/8") and the buttons were almost flush with the acrylic. So, first, I had to break off the tabs. You can use needle-nose pliers for this, but as you can see in picture 2, I quickly learned that this wasn't a good idea. So, I used a combination of an X-Acto knife and a file for the rest.

ADDING PLASTIC CARD SO THE BUTTONS DONT FALL OUT
Picture 3 shows all the buttons correctly prepared. (Except for the one on the far left. ;P )
Now you're thinking, "How are the buttons going to stay in the acrylic? They'll fall right out!" Not to worry, I planned for that. Get some kind of thin plastic or other rigid material. I used an old Dell gift card that had $1.78 left on it. Cut out small strips, and hot glue them to the bottom of the buttons. Now the buttons won't fall out. :D

PADDING
Since I didn't get to use those "mushy" tact switches in my controller, I wanted to add some padding so the buttons could be pressed a bit without actually pressing the tact switch. I found an old foam sheet that goes on top of your mattress, and cut some from that. I glued it to the bottom of the buttons.

Glue another piece of foam to the D-Pad, and you're done with the buttons!

What you need:
Some type of charge plug
Some type of A/V plug with at least 3 contacts
A/V cable (home built or otherwise)
Wire (IDE cable will work)
Soldering Iron
DPST Switch

If you've got built in rechargeable batteries like me, you'll obviously need a charging port. Also, you may want to add A/V out, where you can plug your portable into a larger TV. Not necessary, but it is a very nice feature to have.

USING THE CHARGING PORT
The charging port can easily be bought at Radioshack, or found in old electronics. I'm not sure what it is called, but it is a standard plug. You'll need the plug and the port, so find some. I got mine on an old board I had laying around. It had a headphone jack in it, and a charging port. It is shown in the first picture.

The soldering for the charging port is very simple. Just solder a wire to ground and another to the middle pin of the port. You can tell which is which because the side connected to ground will also be connected to a lot of other contact points as well. The middle pin will usually be isolated. You can see this in the third picture.

WHERE TO ATTACH THE WIRES
The other side of the wires will go to the ground on the console. The positive wire, however, is a different story and will vary between people. For me, it went to the power in line on my charge protection circuit for the Li-ion batteries, but there will be more on that later.

CHARGER
For a charger, any will do. BUT ONLY IF YOU HAVE THE CHARGING CIRCUIT for the Li-ions. You CAN NOT just apply power to the batteries to charge them. Again, if you do not how to properly use Li-ion batteries, PLEASE use NiCD. Ahem. As I was saying, any charger will do as long as it supplies the correct voltage for the protection circuit and it is positive IN and negative OUT.

MAKING THE A/V OUT PORT
For the A/V out, you will need a headphone-type port with at least 3 contacts, which is the standard kind. You also need a headphone plug. You can use company-made stuff, you just have to find the pinout of it. I didn't have any suitable cables, so I made one myself. It is in picture 6.

To prepare the headphone jack, I had to cut the traces on the PCB, because one of the contacts was connected to ground. After that, the ground terminal had to be re-connected to ground. Check out picture 3.

OPTIONAL: HEADPHONE JACK
Picture 4 is if you wanted to use that port as an actual headphone jack. The right and left audio channels are connected, so you get sound in both headphones, even though the NES is mono.

Once the charging and A/V ports are set up, you'll need to add some wires. I soldered a yellow one to the video terminal, a red one to the audio contact, a black one to ground, and a green one to the charging port. See picture 5.

A/V SWITCH
If you want to switch between the internal screen and the external screen, that is fine. This means the picture and sound will be on either the PSone screen or the external screen, not both at once. Or, you could have it so the picture will show up on both screens at once. To do that, just attach the cables that were included with the PSone screen and use the official cable.

I went with option one. Why, I don't know. But I did.
You need a DPST switch, which is Double Pole, Single Throw. In English, that means there are only 2 switch positions (left or right), but it's two switches in one. You can see one in picture 7.

WIRING THE DPST SWITCH
To use this switch, first solder the audio OUT wire from the NES to one of the middle pins. Solder the video OUT wire from the NES to the other middle pin. It is important to get that right. Now, on the audio side, there are two more contacts, both on either side. Solder the audio wire from the screen (the audio in wire) to one of the outer pins. Now take the audio wire from the A/V out port and solder it to the other outer pin. What you have here is a setup that takes the audio from the NES (middle pin) and switches it to either the left outer pin or the right one. In this case, one of those is the PSone screen and the other is the A/V out.
Now you need to do the same for the video, but you MUST MAKE SURE you solder the PSone screen video wire to the SAME SIDE as the PSone screen audio wire. Same goes for the A/V out. Otherwise, you'll have video to one screen and audio to the other or vise-versa.

Make sure you make all the wires relatively long. I didn't do this, and it made things a little more difficult afterwards, so don't be greedy with the wiring. When I was done soldering, I added some hot glue and a zip tie so the wires don't come off from being bent too much.

That's it for the charging port and the A/V jack. You're getting close now! All that's left to do is make the case and mount everything! You're so close now!

Here it is... The biggest part of this project. This is where everything comes together. This step determines how your portable will look and feel in the end. Are you ready? Well, too bad. We're going to discuss the different case options first. ;)

There are quite a few ways you could make a case.

STOCK CASING - A BASIC BOX
The "stock" option - buying something basically pre-made, like a project box from Radioshack. All you have to do is cut holes. Here is a pretty nice-looking NES portable using a large Radioshack project box. It looks very thick.
Here is an amazing-looking N64 portable make from a Lazer Doodle case. This is also a very nice example of Bondo use. (See next paragraph)

FRANKENCASING - USING BONDO
You can do what we call "frankencasing". This is where you use Bondo (a car body filler) to kind of "paste" stuff into your case. Here is a great SNES portable inside a bondo'ed Dreamcast controller. (Scroll down a bit.) As you can see, it looks horrendous right now. The trick is to keep sanding the bondo to make it smooth and level. Take a look at the last page to see how it looks (almost) finished. Here is a guide to frankencasing.

THE ORIGINAL CONSOLE'S CASE
You could use the game console's original case. For old systems, this is great because there is usually tons of room for extra stuff like a screen, battery, etc. Here is a poorly-done N64 portable. It is possible to make nicer-looking ones, this person just didn't spend much time on the case. See how important it is to make a nice case?

POLYCASE.COM
There are online, ready-made solutions. Not specifically for portables, but there are some nice cases online at http://www.polycase.com/ . Two popular cases to use are the ZN-40 and the ZN-45. These are both the same, but the ZN-45 is a bit thicker, so there is more room.
Here is an AMAZING looking N64 portable made with the ZN-40 case. Scroll to about halfway down the page for pictures of this beast.

VACUUM-FORMING
Vacuum-forming is a great option. You can make amazing portables this way. They look fabulous! Here is a great documentation of making a vacuum-forming table. You gotta check it out.

CASES FROM SCRATCH
Lastly, you can make your own case from scratch, which is what I chose to do. I measured all my parts, came up with plans, and had a local plastics company cut the acrylic sheets for me. I then glued them together with a special kind of plastics glue. You shall see in the next step how to do it yourself.

Those are all the types of cases I can think of. These are just general categories. Pick what kind of case you want to do and check out a guide. Or, if you pick the last option, proceed to the next step and see how I made my case.

What you need:
A Dremel with a plastic cutting bit
Tape (Duck Tape works great)
Acrylic pieces for your case (See next paragraph)
A good set of files. Get a square one, too, those are great for the right angles in the D-Pad cross.

GETTING THE PLASTIC
To make this type of case, you first have to measure all your parts to find out the width and height of them. Then, stack all them and find the depth. You can then have a local plastics company cut out the pieces for you. For me, the width of the front and back panels was 8.5" x 6", the top and bottom panels were 8.5" x 2", and the left and right panels were 5 3/4" x 2". That gives a portable with the approximate dimensions of 8.5"x6"x2.5". It could have been thinner, but the plastics company would only cut them to 2" because they were "afraid of cutting their fingers". Oh well. 2" is still very comfortable to hold. One note about the plastic. I found that 1/8" was best. 1/16" was too thin and flimsy and 1/4" was way too thick to work with. For those of you not using the English System (I.E. the lucky people), 3mm acrylic is a good thickness.

You could also order plastic online and cut it yourself. Here is a good website that sells styrene (A fancy name for acrylic which is a fancy name for plastic. Don't you feel educated now?).

Back on track. The first picture shows the pieces proudly displayed on my bedroom carpet. The reason they're blue is because they came with a protective sheet on them so they wouldn't be scratched. As you can see, I already took them off of the left and right panels and one of the top/bottom panels. :)

MAKING THE D-PAD HOLE
So you have your plastic, but now what? Here comes the scary part - making the D-Pad hole. You may have noticed that I have three front and back pieces. Good work, Sherlock. I ordered an extra in case I messed up. ;)

USE THE RIGHT DREMEL BIT!
Get out your trusty Dremel and a plastic cutting bit. I didn't want to go buy a new bit, so I used what came with my Dremel. As you can see in the last picture, it didn't come out so well. Next time I'll buy the proper bit.

Take your NES controller case and tape it where you want the D-Pad to be. We are going to use the controller's original hole as a template for ours. (Picture 2)

RAISE THE PLASTIC
Prop up the plastic on something so that when you go through the plastic, you don't cut whatever is underneath the plastic. I used some school textbooks. (Finally, a use for those!) I used another to hold the plastic down. See picture three.

Turn your Dremel on to the speed appropriate for your plastic-cutting bit. Slowly lower it onto the middle of the template, and drill all the way through, so you create a "starting hole". It helps if you insert the bit at an angle.

CUT AROUND THE TEMPLATE
Carefully start cutting around the inside of the D-Pad template. Don't go all the way to the edge, go just inside it. We will file it down later.

FILE IT OUT
Continue until you get all the way around the template and you cut out the rough shape. Now, take the file and sand down the rough spots. Make the acrylic flush with the template. Try to get it the exact same size.

TEST THE FIT
Once you are satisfied with the hole, take off your template and test the fit of the D-Pad cross. If it fits, great! If it won't go in, have another go with the file. If it's too loose, you might have to re-do it on the extra piece of acrylic. Once you get the D-Pad to fit correctly, you should cut out the A/B and Start/Select buttons.

MAKE THE OTHER BUTTON HOLES
To cut the holes for the other buttons, you should take the controller board you build earlier and hold it in place under the acrylic. Just like the D-Pad, put it where you want the buttons to be.

Take a Sharpie and make the center of the tact switches. Take a drill bit just BARELY larger that your A/B buttons and drill the holes. I don't have a picture of this, sorry.

I didn't have a large enough drill bit, so I had to improvise. I drilled a hole with the biggest bit I had, then used the aluminum-oxide grinding stone that came with me Dremel (the circular orange bit that I used to diffuse my LEDs) and cut the holes with those. Unfortunately, I was not careful enough and make a few cosmetic mistakes, like some scratches on the case. Not a big deal, but you need to be careful of that stuff.

What you need:
Your pieces of acrylic (Including the one with the button holes cut in it)
Acrylic glue
Patience and a place for the glue to set

Now, when I put this together, I was at my dad's house and did not have my camera. I am so sorry. :( The most I can provide you with is pictures of it completed and instructions. Oh, and one more thing. Make sure you take off the protective sheet before you glue the pieces of acrylic together.

Lay your front piece face-down on a soft cloth.

Take one of your top/bottom pieces and spread glue on the bottom side of it. Press it onto the front panel.

Before the glue hardens, take one of the left/right pieces and put glue on the bottom and side of it. Press the bottom onto the front plate, and the side onto the other piece you just glued. This way, you can make sure the pieces are at right angles.

Glue the other two pieces in in the same fashion. DON'T GLUE ON THE BACK PANEL! If you do this, you can't put stuff inside it. Duh. :P

Allow 24hrs for it to dry and cure before you do any more work on it.
 

What you need:
The screen
4 small screws that fit in the PSone screen's holes
Sharpie (any color)
Drill with small bit

This is it! You're really close to being done now. Aren't you excited? I am, 'cause I'm almost done writing this Instructable! Do you know how much work it was!? I started this about 3 months ago and worked on it several times a week! It took forever, man!

Ahem. Now is the part where you install everything inside of the case. I started with the screen, because it was the lowest part in the case.

MAKE VOLUME AND BRIGHTNESS BUTTONS
You need to make buttons for the brightness control and the volume control. I used some old Radioshack switches I had laying around, and pulled out the red button part. See picture one.

I glued them to small pieces of gift card, then glued those to the screen. See pictures two and three.

CLEAN THE PLASTIC
Take a damp paper towel and wipe off the inside of the plastic where you are going to put the screen, then dry it off. You want this part to be completely free of dust and debris, or it will show up later. You might want to wipe down the actual screen also. Of course, this is assuming you are using a transparent case. If you aren't, you'll have to cut a hole for the screen.

PLACE SCREEN AND MARK HOLES
Measure with a ruler (or eyeball it like I did) to find the center of your case and place the screen there. Make sure it it's not at an angle. You don't want the screen to be crooked!

Using the Sharpie, mark where each of the four holes are. Try to get it as exact as you can. Make sure you also mark where the button holes are.

DRILL HOLES FOR SCREWS AND BUTTONS
Using the smallest drill bit you have, drill right where you marked with that Sharpie. If the hole is too small, go to the next drill bit size. You only want to make the holes as big as your screws, maybe half a millimeter larger. Then drill the holes for the screen buttons, in the same manner as above.

SCREW IN THE SCREEN
Screw your screen in. Don't do it too tightly, other you'll cause unnecessary bending of the motherboard. Just tighten all the screws in succession, and check that the board is flat. Just hand tighten the screws.

CHECK FOR DUST UNDER THE SCREEN
Flip the case over and check if there is anything (dust, plastic shards, etc) under the screen. If there is, and it's big enough to bother you, then take it back apart and clean the plastic. Don't mistake debris on the outside for debris on the inside!

What you need:
The controller board you made earlier
The buttons
Screws (I used 6)
Sharpie
Drill with bit the size of your screws
Spacers

You want to be able to PLAY the game, right? Well, then you should probably put in a controller!

The controller boards, I found, were just SLIGHTLY higher than the PSone screen. Therefore, these go in after the screen. I made the mistake of putting the controller in first and made myself do a lot of extra work.

You want to position the board in the correct place and drill the holes, then use screws to hold it in. One thing's different with this, though. With the controller you have to space it away from the case in order for the controls to work correctly.

MARK AND DRILL THE HOLES
Start by marking and drilling your holes. Hold the D-Pad section centered in the hole, and use a Sharpie to mark the hole locations, then drill them. Same idea as the screen. I found that the screen's board was in the way. So I had to use only three screws. To keep the other side symmetrical, I used three screws as well.

INSTALLING THE SCREWS
Get your three screws and put them through the holes in the case. Tape them down so they don't fall out when you flip the case over.

INSTALL AND ADJUST THE SPACERS
Turn over the case and put equal amounts of spacers on each screw. Put the D-Pad in the hole, and put your D-Pad board on the screws. Hold the D-Pad board in place while you flip the case back over. Check the fit of the D-Pad. Did you use too many spacers or too little? Does it take a lot of movement of the D-Pad to press the button of almost none? Adjust the amount of spacers until you find a height that you like. Also, try adjusting the screw you installed on the board earlier with needle-nosed pliers.

Once you have the D-Pad how you like it, install the nuts for the screws. Tighten them down, and give the D-Pad another test. Adjust the screw if need be.

Repeat the procedure for the other set of buttons.

What you need:
NES Board
Screws (and their nuts)
Small right angle brackets
Washers for your screws
Drill with drill bits
Dremel with plastic cutting bit
Hot glue gun

INSTALL BRACKETS TO HOLD THE BOARD
To hold in the NES board, I needed some kind of small right-angle bracket. Luckily, my hardware store had some that were suitable for my needs.

Install the right-angle brackets on the holes that were already in the NES board. See picture one.

MARK RIGHT-ANGLE BRACKET HOLES
Place a piece of cardboard over the existing components and place the NES board on top of that. Mark where the holes on the right-angle brackets are, then drill those out to match the diameter of the screws you'll be using. The reason for the cardboard is to space the NES board away from the rest of the stuff. You don't want it too close or stuff might short, too far and you've got a lot of wasted space.

TEMPORARILY INSTALL THE NES BOARD
Using screws and nuts for spacers (I couldn't find spacers that size), install the NES board. It's a good idea to use washers for this, because there will be a LOT of pressure on these areas. See the pictures, they explain it better than I can.

You probably noticed that there is no hole for the cartridge slot. Well, take an NES game (make sure the NES board is installed already.), and hold the bottom of it firmly to the top of the case, right on top of the cartridge slot. Use a Sharpie to trace around the NES cartridge. Take off the cartridge and check where you marked your Sharpie. Is it centered RIGHT over the cart slot? If not, use a pink school eraser to take off the Sharpie, and do it again.

DISASSEMBLE THE PORTABLE
Now, here comes the fun part. (Not really, this part sucks.) Take apart your portable so far. Yes, that's right. Take out the NES board, controller boards, and screen. You need the empty case again. Get a piece of cardboard about the size of the inside of the case and shove it in there. You want to protect the screen area while you are Dremeling and filing.

CUT THE CARTRIDGE HOLE
Get your Dremel with the plastic cutting bit and start on the cartridge slot hole. Use the same procedure as the D-Pad hole. Start in the middle, then go to the outside. Dremel just inside the marks you made.

FILE THE HOLE DOWN
Once you have the plastic cut out, get your file and smooth out the hole. Use a square file for the corners. Constantly check the fit of the NES cartridge. Once you think you are done, install the NES board but not anything else. Plug in the cartridge (make sure it's facing the right way! (Label faces up, and so do all the components on the NES board)), and make sure everything fits okay.

INSTALL THE SWITCHES
Before you put everything back in, go and do the next step, which is installing the switches. Once you get that done, you can then put the other components back in.

INSTALL THE SPEAKER
It might also be a good idea to install the speaker. :P Drill a bunch of holes, and use a couple dabs of hot glue to hold it in. See the last picture.

What you need:
Drill with plenty of bits

For both switches, I used a drill with various sized bits to make the holes. For the power switch, all I had to do was drill a hole the size of the toggle switch. Then I drilled a smaller hole off to the side to fit the extrusion on the ring around the switch... you know, the one that keeps it from rotating. Check out picture one to see the switch I built.

For the A/V switch, I drilled a few holes in a row, and kept checking the fit and seeing if the switch movement would be hindered at all.

See pictures 2 and 3 to see what I am talking about. (These pictures were taken after the portable was finished, because somehow I didn't take any while I was building it. All that other stuff shouldn't be in the case yet.

What you need:
Back plastic piece
Drill and bits
Hot glue
Long screws and nuts
File

After all this hard work, now you get to finish it all up! You must be bursting with excitement! You probably don't even need these instructions. If you don't, good for you! Go finish your portable! If you do need these instructions, read on.

Hot glue is your friend. But in a transparent case, you don't want to use too much. Only use what you need. Keep that in mind.

GLUING EVERYTHING DOWN
Put simply, in this step you glue everything else (The batteries, charge circuit, A/V board) to the bottom piece of the case. Glue the batteries in the center, because they are the heaviest. You want your portable to be balanced. I used six small blobs of hot glue to hold the battery in. I glued the battery short protection board down, and the charge protection circuit. I glued the A/V board to the bottom, right at the edge. See picture one for the gluing setup, and see 2 for a close-up with all the wires attached. You also need to glue down the NES's regulator. I found that the most convenient place to put it was on the corner of the NES board. First I glued down a piece of cardboard, then the board. Check out picture 3.

In picture three you can see a close-up of the battery protection board. I took out the old battery connector and replaced it with my own. Picture four is the cable for it.

THE CHARGE AND A/V OUT PORTS
Picture 6 shows the A/V out and charge ports. In between them is the charge indicator. When the battery is not fully charged, the light is yellow. When the battery is done, the LED turns green. Some of you may recognize this LED from step 2 of my salvaging PCB parts Instructable. It pays to keep this stuff, man!

MAKE HOLES FOR THE JACKS
With everything glued in place, you need to make the holes for the A/V and charge ports. You need to set the back panel on top of the case, and see where the ports are. Using a file (or your Dremel), cut away a square hole big enough for the charge port. Then you have to drill a hole for the A/V out port. It's a little difficult to do this accurately, but do the best you can. Take a look at pictures seven and eight.

HOLES FOR THE SCREWS
Now, flip your case over and drill holes in the corners, big enough for your long screws. You want the holes to be as much in the corners as possible. Turn your case back over (so it's upside down) and put the back panel on. Mark spots for the screws in the back. Take the panel off and drill the holes.

INSTALL THE SCREWS
Take your screws and put them through the holes in the top and through the bottom. Screw on the nuts, nice and tight. The screws I used weren't really screws, but like a hollow, threaded tube. It's hard to describe in words. Check the last picture to see what I am talking about. These just happened to be long enough for my case.

This is it. The moment of truth. Pop in a cartridge, and flick the power switch. Bask in the glow of the screen. You have made light. And see that it is indeed good.

It's wonderful, isn't it? You finished your very first portable. Why do I say first? Well, in a few days, after you've been playing your handheld 24/7, you realize your life feels empty. You've just gotta make another! These things are addicting, aren't they?

If you think your portable isn't so hot, well, I certainly didn't make a perfect portable, either. Let me list all the flaws of my NES portable:

- There is a big scratch under the screen's plastic. This happened because I didn't put down a piece of cardboard when I was making the cartridge hole.
- The screen's buttons are quite hard to press. I don't know why, but I'll probably fix it sometime.
- The power switch ALMOST hits the cartridge when you flip it on. Not a huge problem, but it's a bit unpleasing aesthetically.
- The cartridge droops downward. I made the cartridge hole too big.
- Some of the button holes for the A/B Start/Select buttons are way bigger that they need to be.
- There is a huge scratch next to the select button. I slipped when I was making the hole bigger with my Dremel.
- There are a few chips in the plastic where I drilled holes.
- The cartridge hole is not straight at all. The sides curve a bit.
- The D-Pad hole is pretty bad. It's hard to see with a transparent case, but there are a few parts that are bigger than they need to be.
- A couple spots where I used hot glue look bad because I used too much.


That's it. I didn't make a horrible portable, but I just need to make sure I don't make these mistakes in my next portable. ;)

Here's stuff I added after I completed my portable.

Picture 1: I found that there was some audio interference, so I replaced the audio and video wires with shielded wire.

Picture 2: I added some rubber disks that I found to the bottom of my screws. Now my portable doesn't slide on tables!

Picture 3: The switch (with WAY too much hot glue) turns on the PSone screen brightness mod.
The plug on the right is for an external battery pack of AAs. See pictures 4,5, and 6, also.

In this step I shamelessly show off my portable. Video coming soon, for now just enjoy the pictures!