Software Defined Radio (SDR) for RF Hacking

A twenty-dollar TV-tuner dongle turns your laptop into a receiver for almost everything across the spectrum — key fobs, sensors, pagers, aircraft transponders, the lot. SDR moves all the radio smarts into software you control: the hardware just samples, you decide what to do with the I/Q. How the signal chain works, finding and reading a signal on the waterfall, capture-and-replay versus rolling codes, decoding a protocol to its fields, the hardware tiers, and the legal lines.