Learn how to build a custom ADS-B aircraft tracking system from scratch in this DEF CON conference presentation. Discover innovative techniques for creating a receiver without relying on expensive SDR chips, as speakers demonstrate how to implement a complete Linux system, signal processing chain, and map visualizer using cost-effective hardware components. Explore the technical challenges and creative solutions involved in developing this efficient tracking system that rivals traditional Raspberry Pi and SDR setups while maintaining lower power consumption and hardware costs.