Program Development


WSJT-X implements communication protocols or "modes" called FT8, JT4, JT9, JT65, QRA64, ISCAT, MSK144, and WSPR, as well as one called Echo for detecting and measuring your own radio signals reflected from the Moon.  These modes were all designed for making reliable, confirmed QSOs under extreme weak-signal conditions.  All but ISCAT use nearly identical message structure and source encoding -- the efficient compression of standard messages used for minimal QSOs.  JT65 and QRA64 were designed for EME ("moonbounce") on the VHF/UHF bands; JT65 has also proved popular and effective for worldwide QRP communication at HF.  JT9 is optimized for the LF, MF, and HF bands.  It  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 and QRA64 are optimized for EME on the VHF and higher bands, and especially the microwave bands from 2.3 to 24 GHz.  FT8 is operationally similar to JT65 but is much faster, using T/R cycles only 15 s long. MSK144 is used for Meteor Scatter on the VHF bands. 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 is now fully implemented within WSJT-X, including automatic band-hopping.

The current General Availability (GA)  release is WSJT-X Version 1.9.1.   A list of new features and enhancements since Version 1.8.0 is available here.  One of the new features is FT8 DXpedition Mode, and to use it you must upgrade to Version 1.9.1. 

DXpedition Mode
User Guide:
 Upgrading from
WSJT-X version 1.4 or later will be seamless.  There is no need to uninstall a previous version or move any files.   

Please note: Versions of WSJT-X labeled with a "-rcx" suffix, for example WSJT-X v1.9.0-rc4, are "Release Candidates" sometimes offered temporarily for beta testing purposes.  If you participate in these beta tests you are expected to report back to the developers on your experiences.  You should upgrade to the GA release when it becomes available.  The -rcx program versions are not suitable for long-term general use.

Release Notes for Version 1.9.1:

Changes between Versions 1.8.0 and 1.9.1:

WSJT-X is a complex program. Be sure to read the online WSJT-X User Guide for Version 1.9.

German translations of WSJT-X User Guide (Version 1.9.1) and associated documents by Enrico Schürrer, OE1EQW: WSJT-X Handbuch, FMT_User, QRA64_EME.

Swedish translation of WSJT-X User Guide (Version 1.6) by Anders Rhodin, SM7VRZ: WSJT-X Användarmanual.

  • Latest full release, Version 1.9: wsjtx-1.9.1-win32.exe.  (runs on Win XP, Vista, Win 7, Win 8, Win10, both 32- and 64-bit).
Installation instructions for Linux can be found here in the User Guide.  Download the package file appropriate for your system, from the list 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 1.9 can be found here in the User Guide.  Download the package file appropriate for your system: 
Source Code:
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.
©2001-2018  by Joe Taylor, K1JT