SDRLive (formerly LinuxSDR) is a linux live cd based on Ubuntu 18.04, and configured for use with software defined radios. A large selection of software has been preinstalled, such as GNURadio, dump1090, GQRX, cubic-sdr, etc. View the changelog on the wiki for a list of installed applications.
Enhanced Machine Controller-based Antenna Range (EMCAR)
EMCAR employs LinuxCNC based machine control (linuxcnc.org) coupled with open source software to implement a measurement system for antenna radiation pattern data (i.e. an antenna range).
HTML_testsystem is a fairly flexible system for taking tests at no cost at all, except for the eventually needed webhosting. It is written entirely in HTML code and JavaScript. An Excel workbook is provided to enter questions in a comfortable way.
Easy to use CW Trainer for Linux. Adaptable for both the Koch and Farnsworth method of learning Morse Code. Makes random tests or can read text from a file. Sample QSO's included. Uses QT user interface. Licensed under the GPL.