KPSK is a PSK31 digital radio communications application for use by 
licensed amateur radio operators and designed specifically for the 
KDE 3.x desktop environment.

Features include:

    * Simple, feature-filled user interface
    * Simultaneous monitoring of up to four PSK31 signals
    * User-configurable waterfall colors, fonts.
    * Auto-scaling waterfall
    * Optimization to provide IMD data only when the measurement is valid
    * Twelve user-defined fixedtexts (TX macros), available by mouse 
       or F1-F12 keys
    * Integral BerkeleyDB-based QSO logbook
    * BPSK or QPSK operation
    * Automatic and manual modes for calling CQ
    * Ability to send an ASCII text file
    * Extensive application documentation

WWW: http://kpsk.sourceforge.net/