Radio allows us to listen to music virtually anywhere. In this worked example, we will determine how coupled oscilations can be used to transmit information. One way to transfer the required radio signal is through Amplitude Modulation (AM) of the electromagnetic waves used to transfer information across the globe.

Most music can be written as a coupled oscillation of multiple harmonics. For simplicity’s sake, let’s look at a hypothetical song that is composed of just two notes with frequencies $f_1$ (440 Hz) and $f_2$ (330 Hz).