The built in peripheral works up to about 100 MHz. Beyond that you use the third/fifth/seventh harmonic.
Because the pi is notionally outputting a square wave, there are plenty of high powered harmonics to use, and from a signal-quality point of view, they are just as good as the fundamental frequency.
Most people view harmonics, spurs and sidebands as unwanted, but with a bit of careful thought they can be controlled to be the exact signal you want...
Because the pi is notionally outputting a square wave, there are plenty of high powered harmonics to use, and from a signal-quality point of view, they are just as good as the fundamental frequency.
Most people view harmonics, spurs and sidebands as unwanted, but with a bit of careful thought they can be controlled to be the exact signal you want...