flDigi, Digital modem program - ilTecnoSociale
fldigi – Digital modem program for Linux, Free-BSD, OS X, Windows XP, NT, W2K, Vista and Win7. flarq – Automatic Repeat reQuest program.Fldigi and Flarq are separate programs that are packaged together as source, binary, and installation files.Building from source requires fltk-1.3.0 library. Download at: download page