Update the "new features" doc.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7000 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

v1.7_Features.txt

@@ -1,13 +1,90 @@
-		New Features in WSJT-X Version 1.7
+		Alpha Release: WSJT-X Version 1.7
-		----------------------------------
+		---------------------------------
 
-1.  New modes: ISCAT, JTMSK, MSK144, QRA64
+Short list of new features
-2.  Newly implemented submodes: JT65B-C, JT9B-H (wide and fast)
+--------------------------
+1.  New modes: ISCAT, JTMSK, MSK144, QRA64.
+2.  Newly implemented submodes: JT65B-C, JT9B-H (wide and fast).
 3.  FT decoder replaces KV decoder for JT65; KVASD is no longer used.
 4.  Improvements to JT4, JT9, and JT65 decoders.
-5.  Multi-pass decoding for JT9, JT65 and WSPR.
+5.  Multi-pass decoding for JT65 and WSPR.
 6.  Many improvements to Rig Control.
 7.  Improved convenience features for EME Doppler tracking.
 8.  Multiple configurations can be saved and restored.
 9.  Sample-file download facility.
 10. Optional auto-sequencing for "fast" modes.
+
+New Modes
+---------
+1. MSK144 is intended for meteor scatter at 50 MHz and higher.
+Designed and tested by K9AN and K1JT, it uses a low-density parity
+check code (LDPC) -- one of the latest-and-greatest areas of active
+research in comminucation theory.  
+
+MSK144 is a direct descendant of JTMSK with a number of improvements
+for better performance on weak and short meteor pings.  The effective
+character transmission rate is about 250 cps, compared with 147 cps
+for FSK441.  Like JT4, JT9, JT65, and JTMSK, MSK144 uses strong
+forward error correction, so message decoding is essentially "all or
+nothing".  You will see little or no "garbage" on your screen.
+
+Standard MSK144 message frames are 72 ms long, compared to 117 ms for
+JTMSK.  The MSK144 waveform allows coherent demodulation for up to 3
+dB better sensitivity.  After QSO partners have exchanged callsigns,
+MSK144 user can use even shorter messages, only 20 ms long.  As in all
+the fast modes in WSJT-X, the 20 ms or 72 ms messages are repeated
+without gaps for the duration of a transmission cycle.  For most
+purposes we recommend a T/R cycle duration of 15 s, but 5 s and 10 s
+sequences are also supported.
+
+An MSK144 signal occupies the full bandwidth of a typical SSB
+transmitter, so transmissions are always centered at an offset of
+1500Hz.  For best results, selectable/adjustable Rx and Tx filters
+should be set to provide the flattest possible response over at least
+300 - 2700 Hz.  The maximum permissible frequency offset between you
+and your QSO partner is ± 200 Hz, and less is better.
+
+2. QRA64 is a designed for EME and other weak-signal use.  Its
+internal code was designed by Nico Palermo, IV3NWV.  It uses a "Q-ary
+Repeat Accumulate" code, another one of the latest research areas in
+communication theory.  The QRA64 code is inherently better than the
+Reed Solomon (63,12) code used in JT65, yielding already a 1.3 dB
+advantage.  QRA64 uses a new synchronizing scheme based on a 7 x 7
+Costas array, so you will not see a bright sync tone at the lowest
+tone frequency.  This change yields another 1.9 dB advantage.
+
+In most respects our implementation of QRA64 is operationally similar
+to JT65.  QRA64 does not use two-tone shorthand messages, and it makes
+no use of a callsign database.  Rather, additional sensitivity is
+gained by making use of "already known" information as a QSO
+progresses -- for example, when reports are being exchanged and you
+have already decoded both callsigns in a previous transmission.  QRA64
+presently offers no message averaging capability, though that may be
+added.  In our early tests, many EME QSOs have already been made using
+submodes QRA64A-E on bands from 144 MHz to 10 GHz.
+
+3. ISCAT is essentially the same as in recent versions of program WSJT.
+For details consult the WSJT User Guide:
+http://physics.princeton.edu/pulsar/K1JT/doc/wsjt/
+
+
+Program Setup
+-------------
+
+Some of the new program capabilities are enabled when you check
+"Enable VHF/UHF/Microwave features" on the Settings | General tab.
+For MSK144 mode, we suggest setting "T/R 15 s" and "F Tol 100 Hz";
+check "Sh" to enable the use of short messages and "Auto Seq" for
+auto-sequencing.  For QRA64 mode, set Tx and Rx frequencies to 1000
+Hz.  We encourage you to check "Save all" when making tests, and to
+save any of the resulting .wav files that might help us to improve
+program performance or behavior, or to illustrate a problem that you
+identify.
+
+
+Final Comments
+--------------
+
+We will be grateful for any and all reports from test users that may 
+help us to further improve WSJT-X.  Send your reports to 
+wsjtgroup@yahoogroups.com.