JS8Call is an experiment in combining the robustness of FT8 (a weak-signal mode by K1JT) with a messaging and network protocol layer for weak signal communication. The open source software is designed for connecting amateur radio operators who are operating under weak signal conditions and offers real-time keyboard-to-keyboard messaging, store-and-forward messaging, and automatic station announcements.
JS8Call is a derivative of the WSJT-X application, restructured and redesigned for message passing using a custom FSK modulation called JS8. It is not supported by nor endorsed by the WSJT-X development group. While the WSJT-X group maintains copyright over the original work and code, JS8Call is a derivative work licensed under and in accordance with the terms of the GPLv3 license. The source code modifications are public and can be found in this repository: https://github.com/js8call/js8call .
JS8Call-improved is continued development of the original JS8Call project. Most of the same developers work on both projects. With JS8Call-improved we are able to implement bug fixes and features must faster so development can proceed at a faster pace. It is likely that bug fixes and/or features in JS8Call-improved may not be incorporated into the official JS8Call project.
Like JS8Call, JS8Call-improved is licensed under the GPLv3, the Qt libraries used by JS8Call-improved are licensed under the LGPL. See LICENSE for the details. All copyrights remain with the original holders. Source code for JS8Call-improved is here