aperture: what's on the air from 500 kHz to 1.77 GHz

I’ve already written up two things I did with this $25 RTL-SDR Blog V4 dongle in San Francisco: three 433 MHz weather sensors and ships and aircraft over SF Bay. This post is the wider look at what’s on the air around me: the V4’s whole 500 kHz to 1.766 GHz range (datasheet), whether strong FM stations overload the receiver, and a 1560 kHz AM station that turned out to be an empty channel. ...

September 26, 2026 · 16 min · Derek Welty