Radio, like most else, has gone digital. In the early days of digital signal processing, pioneers realized that many modulation and demodulation techniques could be performed by digital computation.
As computers became cheaper and faster and integrated circuits became cheaper and faster, it was inevitable that the guts of radio receivers and transmitters would be mostly digital and that computers would do much of what went on inside new radios.
This post will describe the initial exploration of GQRX and RTL-SDR here at Dismal Manor. Most of what is already written on the Internet neglects to mention a couple of details the Moocher learned the hard way. Find out what these are after the break.