Since we started modding the Master System 2 on the previous post, I thought I should go ahead and fix another omission of the system. A freaking power led! How would you know when the system is on without one? Well, that’s an easy fix but, since I already mentioned in the previous post that I don’t like modifying these old consoles in a irreversible way, I decided to go the extra mile and 3d print a new power button with the necessary space to let a led shine through it, so I could save the original part.
Link here: https://www.thingiverse.com/thing:4915513

So first thing is first. I already had a bunch of color cycling 5mm leds lying around from my NES mod, so I decided to use one of these as my power led for the SMS2. These are quite fun, since they automatically cycle through many different colors when power is applied.

The way you connect the led is by using 2 pins of this little thingy (which is a Voltage Regulator), which is accessible inside the Master System 2 even without removing the metal shield:

The led fits nicely inside the 3d printed power button that replaced the original one and the pins and wire come out of the side, so it does not affect its usage which is to actually, well, power the system on and on by flipping the switch below it.

And that is all you need to do. Here is a video of the result, in real life it does not shine so brightly and it looks very nice when powered on.

A little known fact about the NES is that there are versions of the console that do not support all the controllers out there. The PAL version that came with controllers that have the NES-004E engraved on the back ONLY support controllers with this engraving and nothing else. Controllers from the NTSC version will not work and nor will any knock-off controllers from China.

I recently replaced my controller’s insides with the excellent DIY kit from 8BitDo that turns the original controller into a wireless version that works just as well.

I am using this with the also excellent NES retro receiver and works flawlessly. Since I am using the original chassis and buttons, the feeling is almost identical to the original controller sans the cable. The system worked fine on my PAL NES-E console as well.

But all that changed when I bought a couple of (admittedly very nicely built) knock-off controllers from China. I plugged both on either port on my NES and nothing seemed to work. It would be a huge coincidence for both the controllers to be faulty (I knew the console and both ports worked) so I investigated further.

It turns out that my console only supported NES-004E controllers (the 8bitdo receiver obviously is handling the issue fine). By disassembling the console, I noticed that each controller port was connected to some kind of board which in turn was connected to the main board. These boards had several diodes that obviously prevented other versions of the NES controller to work.

The solution turned out to be surprisingly easy. All one needs to do is bridge all the diodes (essentially bypassing them). You could also remove the whole board and connect the cables directly on the port but I felt this solution was easier to do and more elegant.

This modification is only useful if your NES has this board between each controller port and the main board and you have controllers you want to use that are not recognized. It can also be done in the same way on both ports. Doing this mod does not have any drawbacks, the original controller work just fine. But now, your NES is controller-region-free!

This is the first of a series of old consoles modding posts, some to add functionality and some purely cosmetic. I will start with the simplest of them all, changing the power LED of a Nintendo Entertainment System.

When the NES came out in 1985, electronic power LEDs used colors that were available at the time, red or green ones. Blue LEDs were not around at the time. They were invented relatively recent and they gave their inventors Isamu Akasaki, Hiroshi Amano and Shuji Nakamura, the Nobel prize in 2014.

Changing the NES power LED to blue, in my opinion gives the 80s device a more 21st century feel and it’s super easy to do. All you have to do is unscrew the NES, remove the mainboard and get to the POWER and RESET board on the left. Use a soldering iron to remove the existing LED, while bending it a bit to the back to remove it from the plastic clear channel.

At this point you are ready to put the new LED in. Just be careful with polarity. LEDs, as the D in their name suggests are diodes, which means there is a correct way and a wrong way to put them in the circuit.

The LED symbol shows you the way. The Anode is where you need to use the long leg of the LED (positive) and the Cathode where you use the short one (negative). If you mess it up, it doesn’t hurt anything, but it will not light up, which is the whole point of a LED.

Solder the two legs at the bottom and bend the LED back in the clear channel like in the picture below.

If you get everything correctly and try to power up the NES, you will be greeted with a beautiful LED light. Put back everything and you should be done. Enjoy the 21st century light show!