4 ms·
> There are ways to do a full software defined radio from a pi by using the I2S hardware, and that can transmit GPS, 433 MHz garage door openers, and various ot
by miegl 4y ago
> There are ways to do a full software defined radio from a pi by using the I2S hardware, and that can transmit GPS, 433 MHz garage door openers, and various other things.
Wait, we can do sine wave up to ~1.5 GHz using the built-in PCM/I2S peripheral?
- pifm_guy 4y agoThe 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...