ADS-B aircraft tracking has long been done with Raspberry Pi’s and SDRs. We set out to build our own receiver from the ground up, but without resorting to expensive and power-hungry SDR chips. Join us for a behind-the-scenes look as we walk through how we were able to (ab)use hardware to squeeze an entire Linux system, custom signal processing chain, and map visualizer into a chip that costs less than most microcontrollers.