
60 Make: Radio
What if a transmitter creates a square wave? It’s a strange fact that you
can build a square wave by assembling a lot of sine waves of increasing
frequency. This is suggested in Figure
3-10
, where the bold red curve is the
result of adding all the other waves of different colors. The more curves you
add of higher frequencies, the closer the red curve can get to being a square
wave. (Of course, the size of each additional wave has to be just right, and
there is a formula that defines this for you, although it’s too complex for me
to deal with here.)
The curves of higher frequency are known as the harmonics of the frequency
of the ...