ERRATA.TXT lists known problems and anomalies in the data on this and
previous volumes.  The most up-to-date version of this file is available
online at:

  http://www-pw.physics.uiowa.edu/cluster/dvd/ERRATA.TXT

For issues relating to the interpretation of WBD data, please see the Cluster
Interpretation Issues web page, available at:

  http://www-pw.physics.uiowa.edu/cluster/interpretation_issues/

and also at the Cluster Active Archive (http://caa.estec.esa.int/caa/).

1. Known Cluster 2 Problems

   WBD data received from Baikonour tests just prior to launch in 2000
   revealed various problems with the WBD transfer frames that most likely
   originate in the Cluster Onboard Data Handling System (OBDH) on Cluster 2
   only.  Because these problems were discovered so late, it was not possible
   to do further diagnostics and correct the problems since it was felt
   that most of the problems could be worked around in ground processing.
   The following are the problems that were identified and how they are
   handled in LEVEL1 processing:

   (a)  Instrument Counter Values

   The WBD instrument has a counter which is reset every 5.15 seconds.
   On Spacecraft 2, the value of this counter is not always read out
   correctly after a reset, resulting in an incorrect counter value being
   placed in the data record. After processing, these incorrect values
   remain in the level one files, although any errors they might have
   introduced into the time stamp calculations have been corrected.

   (b)  Science Data Errors

   When a science data point on spacecraft 2 has a value of 80 (hexadecimal),
   the following data point will sometimes have an invalid, but predictable,
   value.  Iowa replaces the invalid value with the value 255 to signify that
   the value is bad and not deterministic.  We provide a simple procedure
   which replaces the apparently incorrect value with the average of the two
   adjacent values (see FIX_SC2.C in the SOFTWARE/CLU2_FIX directory).  This
   procedure should be run before any calibrations are applied.

   (c)  WBD Status Errors

   Occasionally, any one of the WBD status bits can be corrupted.  These
   status bits provide information about the mode and gain state of the
   instrument.  Iowa corrects the decommutated status bits written into the
   level 1 files when this status bit is a mode bit, such as antenna being
   used, bandwidth, and conversion frequency, but does not correct it when it
   is a gain state bit because it is difficult to determine what the correct
   gain state should have been.  Because the calibration for the WBD data
   depends on knowing the correct gain state, the calibration that is applied
   to a frame with an errant gain state will be incorrect.  This is usually
   apparent as a more or less intense frame slice compared to those on either
   side of it in the 30 second spectrograms (gifs) that are produced for every
   pass (note, however, that a gain state error is certainly not the only
   possible cause of such an artifact on the spectrograms).

2. Software and document updates

   2004-02-16:  In SOFTWARE/EXAMPLES, the files CLOG.C, R_WBD_WF.C,
   WBDL1LIST.C, and MAKEFILE were updated.  The corresponding executables
   in the SOFTWARE/EXAMPLES/BIN/* directories were also replaced.  These
   updates will appear on volumes after WBD_20010624_30_A.

   2004-03-10:  In SOFTWARE/CLU2_FIX, the file FIX_SC2.C was updated to
   accomodate the case where the "bad" data value had been set to 255.

   2004-06-07:  SOFTWARE/EXAMPLES/WBDL1.H macro named
   WBD_OBT_CTIB_subsec(p) was corrected.  The Level 1 generation program
   put the 20-bit value in bytes 1253-1255 instead of 1252-1254 and the
   macro was modified to accomodate the error.  The format documents,
   test output files, and executable binary programs have also been
   updated to conform.  Our thanks to Jan Soucek for identifying this
   problem.

   2006-07-12:  INSTDESC.TXT and WBFORMAT.TXT were updated with more
   precise conversion frequency values.  The R_WBD_WF.C example was
   updated to open the highest available version data file.  CALIBRATE.C
   was updated to include conversion of B-antenna data to nT.  The following
   files were updated:

     SOFTWARE/EXAMPLES/EX_README.TXT
     SOFTWARE/EXAMPLES/R_WBD_WF.C
     SOFTWARE/EXAMPLES/BIN/LINUX_INTEL_FEDORACORE5/CLOG
     SOFTWARE/EXAMPLES/BIN/LINUX_INTEL_FEDORACORE5/R_WBD_WF
     SOFTWARE/EXAMPLES/BIN/LINUX_INTEL_FEDORACORE5/WBDL1LIST
     SOFTWARE/EXAMPLES/BIN/SUN_SPARC_SOLARIS7/R_WBD_WF
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/CLOG.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/CYGWIN1.DLL
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/DIFF.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/DOS2UNIX.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/MD5SUM.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/R_WBD_WF.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/UNIX2DOS.EXE
     SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/WBDL1LIST.EXE

   2006-08-16:  All documentation was revised before final submission to
   the Cluster Active Archive (CAA).  These revisions were carried out
   primarily to make the wording in the documentation more clear and
   concise and to provide a more expanded explanation of various problems
   and of the time stamps (TIMES.TXT renamed TIMETAGS.TXT) contained in
   the level 1 files.  The documents that were revised are:

     ERRATA.TXT
     INSTDESC.TXT
     README.TXT
     TIMETAGS.TXT (previously named TIMES.TXT)
     WBFORMAT.TXT

   2007-04-26:  Example software was updated to handle burst mode data and
   correct minor bugs.  The BIN directory with executable code was removed.
   Documents were updated with additions for burst mode and corrections for
   the software changes.  Note that the previous WBFORMAT.TXT does not
   accurately describe the location of burst mode header items.  However, no
   burst mode level 1 data have previously been distributed.  The following
   directory tree was removed:

     SOFTWARE/EXAMPLES/BIN

   The following files were updated:

     ERRATA.TXT
     README.TXT
     SOFTWARE/EXAMPLES/EX_README.TXT
     SOFTWARE/EXAMPLES/R_WBD_WF.C
     SOFTWARE/EXAMPLES/WBDL1.H
     SOFTWARE/EXAMPLES/WBDL1LIST.C
     WBFORMAT.TXT

3. Volume-specific errors

   WBD_20010203_14_A

      SOFTWARE/EXAMPLES/WBDL1.H was formatted with LF instead of CR/LF
      line termination.

      Several Cygwin DLL files are missing from
      SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/ which prevent the
      example executables from running stand-alone from this directory.

   WBD_20010215_28_A

      SOFTWARE/EXAMPLES/WBDL1.H was formatted with LF instead of CR/LF
      line termination.

      Several Cygwin DLL files are missing from
      SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/ which prevent the
      example executables from running stand-alone from this directory.

   WBD_20010301_17_A

      The volume label recorded on the disk is WBD_20010302_17_A.

      Several Cygwin DLL files are missing from
      SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/ which prevent the
      example executables from running stand-alone from this directory.

   WBD_20010318_30_A

      Invalid entries for MD5LF.TXT and MD5CRLF.TXT exist in each
      of the files by the same name.  (Old files were not removed
      prior to generating new versions, so "md5sum -c" will fail
      for those two entries.  These failures can be ignored.)

      Several Cygwin DLL files are missing from
      SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/ which prevent the
      example executables from running stand-alone from this directory.

   WBD_20010331_31_A

      Several Cygwin DLL files are missing from
      SOFTWARE/EXAMPLES/BIN/WINDOWS_INTEL_CYGWIN/ which prevent the
      example executables from running stand-alone from this directory.

