You'll need a variety of stuff to do this project. The less tools you have for working with electronics, the more you'll have to spend to make it, so either buy all the tools, or find someone that has them and buy them a nice lunch at Applebees then ask nicely if you can use their tools.
Tools you really should have:
-A soldering iron with a small point tip
-A small pair of wire cutters
-A small needle nose pliers
-Wire strippers (You'll be stripping really small gauge wire, 26 or less)
-A Dremel motor tool with a carbide cutter (for cutting the perf board and drilling holes)
Most of the electronic parts can be bought from Mouser Electronics
. I'll list the supplier that I got various other supplies from for other parts. Feel free to innovate if you can find a better/cheaper place to get something, and post it here for all of us!
-Plastic Leg Tips (Home Depot, 89105)
-1/4" coaxial cable staples (home depot psw-1650)
-Pre-punched perfboard ( Radio Shack
-50 ft PS/2 extender cable ( Monoprice
-White electrical tape (Frys)
-A 5 volt power supply capable of handling at least 700 mA, or more depending on the power requirements of your light LEDs. I used a power brick from an old zip 250 drive, that puts out 1 amp at 5v.
For electronic parts, you can download the excel spreadsheet of the components I used by clicking the excel spreadsheet I linked here. To make your life really easy, create a mouser account, click here
, select the second and third columns of the spreadsheet and copy and paste them into the BOM importer.
2x 940nm IR LEDs: you can get these at mouser as well, but I found the best directional LEDs I could get came from Newark Electronics
. If you want to sub in another LED for these, you'll need something that operates at 940nm and is fairly directional (to prevent it from dissipating over the distance to the sensor).
You'll also need a bunch of LEDs for your stairs or whatever room you want to light up. Once you choose your LEDs, you can plug in the specs for them here
to calculate what resistors you'll need and how to configure them.
Overall, you should be able to do this project for about $60 as long as you don't destroy components while building it. If you're prone to soldering chips to kingdom come, make sure to buy spares.