Program Development


WSJT facilitates basic digital communication using protocols explicitly optimized for a  number of different propagation modes. 

The latest release, WSJT 9.7, includes the JTMS mode, designed for meteor scatter at 144 MHz and higher. 

ISCAT now has two sub-modes.  ISCAT-B is the original ISCAT mode with total bandwidth 1809 Hz.  ISCAT-A runs at half the rate, uses half the bandwidth, and (for average decodes on steady signals) is about 1 dB more sensitive.  It has been found very effective for making aircraft scatter QSOs at 10 GHz.  ISCAT-B probably remains the best mode for 6 meters, but experimentation is encouraged!

JT65B2 and JT65C2 use the same tone spacing as JT65B and JT65C, respectively.  They are keyed at twice the rate, and T/R sequences are 30 seconds rather than one minute.  Sensitivity of the fast modes is 3 dB worse than the standard modes.  The B2 and C2 modes allow EME contest QSOs to be made at twice the rate, up to about 20 QSOs per hour. 


See User's Guide for details.
  • FSK441 for meteor scatter
  • JTMS for meteor scatter
  • ISCAT for ionospheric scatter 
  • JT65 for EME at VHF/UHF, and for HF skywave propagation
  • JT4: for EME and tropospheric propagation on microwave bands


Important note: in Vista, Windows 7, and Windows 8 install WSJT to a directory such as C:\WSJT or C:\HamRadio\WSJT rather than the default C:\Program Files\WSJT.  (Otherwise, you might need to set some read/write permissions explicitly.)

User's Guide and Reference Manual

(English version is included with program download.)


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©2001-2014 by Joe Taylor, K1JT