Step 17: Build the Power Regulator
Medium-sized piece of perfboard
7805 Regulator (From the RF box)
Heatsink (You can use the one from the RF box if you like)
Two 0.1uf Capacitors
1 - 10uf Capacitor
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.
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.