To: Users of WSJT-X — especially those interested in radio contesting
From: WSJT Development Group
As you know, we have been developing a protocol called FT4 for use in radio contesting. A new version of FT4 is now available for testing in WSJT-X 2.1.0-rc6.
PLEASE NOTE THAT FT4 IN RELEASE CANDIDATE 6 IS NOT COMPATIBLE WITH THAT IN ANY PREVIOUS RELEASE.
Therefore: Please stop using WSJT-X 2.1.0-rc5. If you wish to use FT4 after today or to take advantage of other recent program corrections or enhancements, you should use WSJT-X 2.1.0-rc6.
MOCK CONTEST SESSION
A special session for testing the contesting features of FT4 is scheduled for six hours from
June 4, 1900 UTC through June 5, 0100 UTC:
Tuesday afternoon/evening, North American time, starting about 48 hours from now. Get on the air whenever you can during this mock contest session, using dial frequency 7.090 or 14.080 MHz, as appropriate to the time of day. As in previous tests, be sure to check “RTTY Roundup messages” on the Settings | Advanced tab.
Here’s a list of changes, improvements, and bug fixes that have been made since WSJT-X 2.1.0-rc5:
IMPORTANT CHANGES TO THE FT4 PROTOCOL *** NOT BACKWARD COMPATIBLE ***
– T/R sequence length increased from 6.0 to 7.5 seconds
– Symbol rate decreased from 23.4375 to 20.8333 baud
– Signal bandwidth decreased from 90 Hz to 80 Hz
OTHER FT4 IMPROVEMENTS
– Allowable time offsets -1.0 < DT < +1.0 s
– Tx4 message with RRR now allowed, except in contest messages
– Audio frequency is now sent to PSK Reporter
– Add a third decoding pass
– Add ordered statistics decoding
– Improved sensitivity: threshold S/N is now -17.5 dB
– Improved S/N calculation
– In FT4 mode, Shift+F11/F12 moves Tx freq by +/- 100 Hz
– Improvements to accessibility
– Updates to the User Guide (not yet complete, however)
– New user option: “Calling CQ forces Call 1st”
– N1MM Logger+ now uses the standard WSJT-X UDP messages
– OK/Cancel buttons on Log QSO window maintain fixed positions
– Put EU VHF contest serial numbers into the ADIF SRX and STX fields
– Fix generation of Tx5 message when one callsign is nonstandard
– Fix a bug that prevented use on macOS
– Fix a bug that caused mode switch from FT4 to FT8
– Fix a bug that caused FT4 to do WSPR-style band hopping
– Fix a bug that caused a Fortran bounds error
Release candidate WSJT-X 2.1.0-rc6 will be available for beta-testing through July 21, 2019. It will be inoperable during the ARRL June VHF QSO Party (June 8-10) or ARRL Field Day (June 22-23). It will permanently cease to function after July 21, 2019. If all goes according to plan, by that time we will have made a General Availability (GA) release of WSJT-X 2.1.0.
Downloadable installation packages for WSJT-X 2.1.0-rc6 under Windows, Linux, and macOS are available on the WSJT-X web page:
— 73 from Joe, K1JT; Steve, K9AN; and Bill, G4WJS