Gpredict is a real time satellite tracking and orbit prediction program. Besides the general orbital data for satellites, gpredict can also calculate the footprint, visibility, doppler shift, signal loss, and signal delay for each satellite relative to one or more ground stations. The calculated data can be viewed in tables, on maps, or on polar graphs.
CWirc is a plugin for the X-Chat IRC client to transmit raw Morse code over the internet using IRC servers as reflectors. The transmitted Morse code can be received in near real-time by other X-Chat clients with the CWirc plugin. CWirc tries to emulate a standard amateur radio rig: it sends and receives Morse over virtual channels, and it can listen to multiple senders transmitting on the same channel. Morse code is keyed locally using a straight or iambic key connected to a serial port, or using the mouse buttons, and the sound is played through the sound card, or through an external sounder.
gMFSK is a multimode HF terminal program that can send and receive many digital conversational modes typically used by radio amateurs on HF. It uses the computer soundcard to interface to an SSB capable transceiver. All digital signal processing is done in the main CPU so any soundcard should work.