Program Development


WSJT-X implements communication protocols or "modes" called JT4, JT9, JT65, and WSPR, as well as one called Echo for detecting and measuring your radio signals reflected from the Moon.  The JTxx modes were all designed for making reliable, confirmed QSOs under extreme weak-signal conditions.  They use nearly identical message structure and "source encoding," the efficient compression of standard messages.  JT65 was designed for EME ("moonbounce") on the VHF/UHF bands, and has also proved very popular and effective for worldwide QRP communication at HF.  In contrast, JT9 is optimized for the LF, MF, and HF bands.  JT9 is about 2 dB more sensitive than JT65 while using less than 10% of the bandwidth.  With either JT9 or JT65, world-wide QSOs are possible with power levels of a few watts and compromise antennas.  JT4 is particularly optimized for EME on the microwave bands from 2.3 to 24 GHz.  Finally, as described more fully on its own page, WSPR mode implements a protocol designed for probing potential propagation paths with low-power transmissions.  WSPR has now been fully implemented within WSJT-X, including automatic band-hopping, so all modes are available in a single program.

The current release of WSJT-X is Version 1.6.0, and it offers flexible control of nearly all modern transceivers.  Upgrading from WSJT-X versions 1.4 and 1.5 will be seamless; there is no need to uninstall a previous version or move any files.  If you are upgrading from WSJT-X v1.3 you will need to copy your log files into a new location and re-enter your setup information.  Release notes for Version 1.6 are provided here.

Future plans

Future versions of WSJT-X will include other popular modes from WSJT and its sister programs, starting with ISCAT and JTMSK.


Be sure to refer to the online WSJT-X User Guide for Version 1.6.

Installation instructions for Linux can be found here in the User Guide.  Download the package file appropriate for your system, from the lilst below.  (Versions installable with "apt-get" and "yum" will be made available as soon as our package maintainers create the packages.)
Macintosh OS X: 
Installation instructions for version 1.6 can be found here in the User Guide.  Download the package file appropriate for your system: 
Source Code:
Communication among contributing developers takes place on the wsjt-devel email reflector.  The package posted here contains all source code for WSJT-X as well as a snapshot of the Hamlib 3 sources and a CMake script to build WSJT-X on any supported platform.

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