Learning the fundamentals behind radio really blew my mind at the time (years ago), and having Claude there to help visualize things must be an incredible boon.

Everything in SDR has an analog equivalent, from local oscillators to PLLs to filtering. In fact most of it simply is a direct implementation of decades-old analog concepts.

But the underlying math is what I found most incredible, where the "true" representation of a signal is complex, and that every real (both in the ordinary and mathematical sense) signal is actually the sum of a positive and negative frequency, such that the complex component cancels out. Phase becomes much more comprehensible as simply the angular component of the signal, and frequency is the derivative of phase. All of this had the indirect effect of improving my understanding of complex numbers as well.