This book is intended for Amateur Radio Operators, Shortwave Listeners, and anyone interested in radio as a hobby. It includes sections on how different types of software defined radios work, the advantages of using them, and how they are tested. It also covers future trends including the development of Direct Fourier Conversion. There is a big section with tips for PowerSDR users and sections about other commonly used SDR software, plus a comparison of the basic specifications of 65 different S