[600MRG] Fwd: Fwd: Release Candidate: WSJT-X 2.3.0-rc1

[Larry]

The first public candidate release of WSJT-X 2.3.0 is now available for 
download and use by beta testers.  This release is your first chance to
try two new modes designed especially for use on the LF and MF bands, 
and to provide feedback to the WSJT Development Team.  The new modes are:

  - FST4, for 2-way QSOs.  Options for sequence lengths from 15 seconds
    to 30 minutes, with threshold sensitivities from -20.7 to -43.2 dB in
    a 2500 Hz reference bandwidth.

  - FST4W, for WSPR-like transmissions.  Sequence lengths from 2 minutes
    to 30 minutes, threshold sensitivities from -32.8 to -44.8 dB.

FST4-60 is about 1.7 dB more sensitive than JT9, largely because it uses 
multi-symbol block detection where appropriate. With AP decoding in FST4 
the advantage can be as much as 4.7 dB. Additional sensitivity details 
with respect to path Doppler spread are illustrated in the following 
graph comparing JT9 and FST4-60:
https://physics.princeton.edu/pulsar/k1jt/jt9_vs_fst4.pdf

FST4W-120 is about 1.4 dB more sensitive than WSPR, and FST4W submodes 
with longer transmissions have proportionally better sensitivity. 
Decoding probabilities are plotted as a function of SNR on the additive 
white Gaussian noise (AWGN) channel for WSPR and all FST4W submodes 
here: https://physics.princeton.edu/pulsar/k1jt/wspr_vs_fst4w.pdf

Tests over the past several months have shown FST4 and FST4W frequently 
spanning intercontinental distances on the 2200 m and 630 m bands. 
Further details and operating hints can be found in the "Quick-Start 
Guide to FST4 and FST4W":

https://physics.princeton.edu/pulsar/k1jt/FST4_Quick_Start.pdf

We strongly recommend that users of JT9 and WSPR on the LF and MF bands 
should migrate to the more sensitive modes FST4 and FST4W.


Links to installation packages for Windows, Linux, and Macintosh are 
available here:
http://physics.princeton.edu/pulsar/k1jt/wsjtx.html
Scroll down to find "Candidate release:  WSJT-X 2.3.0-rc1".

You can also download the packages from our SourceForge site:
https://sourceforge.net/projects/wsjt/files/
It may take a short time for the SourceForge site to be updated.

WSJT-X is licensed under the terms of Version 3 of the GNU General 
Public License (GPL).  Development of this software is a cooperative 
project to which many amateur radio operators have contributed.  If you 
use our code, please have the courtesy to let us know about it.  If you 
find bugs or make improvements to the code, please report them to us in 
a timely fashion.

We hope you will enjoy using this beta release of WSJT-X 2.3.0.  Please 
report bugs by following instructions found here in the User Guide:
http://www.physics.princeton.edu/pulsar/K1JT/wsjtx-doc/wsjtx-main-2.3.0-rc1.html#_bug_reports

      -- 73 from Joe, K1JT, Steve, K9AN, and Bill, G4WJS