Remember, all signals are analog, even those that pose as digital. Ever hear of signal integrity? Now probably not given the pedesctrian speeds you work at. You should come to DesignCon, a digital deisgn conference that's really all analog.
I suggest downloading a tone generator app, which hopefully will give you something close to a sine wave (another analog thing). I suggest checking the output on an oscilloscope set to give you at FFT (fast Fourier Transform for you digital folk). You should see the fundamental tone but you may see harmonics. Hmm maybe I can write an article comparing tone generator apps.
Replay available now: A handful of emerging network technologies are competing to be the preferred wide-area connection for the Internet of Things. All claim lower costs and power use than cellular but none have wide deployment yet. Listen in as proponents of leading contenders make their case to be the metro or national IoT network of the future. Rick Merritt, EE Times Silicon Valley Bureau Chief, moderators this discussion. Join in and ask his guests questions.