Digital Signal Processing Technology -- Essentials of the Communications Revolution. An understandable presentation and reference on DSP in contemporary communications technology.

Morse Code for Radio Amateurs -- Includes a free CD of audio and computer programs.

ARRL's VHF Digital Handbook -- Dive into the digital radio universe!

The ARRL Software Library for Hams 2.0 -- CD-ROM, Version 2.0. Quick access to utilities, applications and information.

Nifty E-Z Guide to PSK31 Operation -- Now Shipping! -- A complete guide for implementing PSK31!