[Simon Inns] has put together a lesson in digital logic which
shows you how to build your own gates using transistors. The
image above is a full-adder that he fabricated, then combined
with other full adders to create a 4-bit computer. Don’t know
what a full adder is? That’s exactly what his article is for,
and will teach you about binary math and how it is calculated
with hardware. There’s probably at least a week’s worth of
studying in that one page which has been further distilled into
the five-minute video after the break. Although building this
hardware yourself is a wonderful way to learn, there’s a lot of
room for error. You might consider building these circuits in a
simulator program like Atanua, where you can work with logic
gate symbols, using virtual buttons and LEDs as the outputs.
Once you know what you’re doing with the simulator you’ll have
much more confidence to start a physical build like the one
[Simon] concocted. Finding this project a little too advanced?
Check out our Beginner Concepts