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JT65CODE(1)			  WSJT-X Manual 		     JT65CODE(1)

NAME
     jt65code,	jt9code,  jt4code,  qra64code, ft8code, msk144code - Weak signal
     communications encoding support utilities.

SYNOPSIS
     jt65code "MESSAGE"

     jt65code [OPTIONS]

     jt9code "MESSAGE"

     jt9code [OPTIONS]

     jt4code "MESSAGE"

     jt4code [OPTIONS]

     qra64code "MESSAGE"

     qra64code [OPTIONS]

     ft8code "MESSAGE"

     ft8code [OPTIONS]

OPTIONS
     -t
	 Prints a selection of messages alongside  their  corresponding  decoded
	 form  and  types.  With ft8code prints a selection of short format mes-
	 sages

     -T
	 As -T but for ft8code prints long format messages.

DESCRIPTION
     jt65code, jt9code, jt4code, and ft8code are utility programs that	let  you
     explore the conversion of user-level messages into channel symbols or "tone
     numbers." These programs can be useful to someone designing a beacon gener-
     ator  for	JT9 or JT65, or for studying behavior of the error-control codes
     for each of the protocols.

     Channel-symbol values for JT9 run from 0 to 8, with 0 representing the sync
     tone. The total number of symbols in a transmitted message is  85.  To  run
     jt9code,  enter  the  program  name  followed  by a JT9 message enclosed in
     quotes. In Windows the command and program output might look like this:

	 $ jt9code "G0XYZ K1ABC FN42"
	 Message:   G0XYZ K1ABC FN42
	 Channel symbols:
	  0 0 7 3 0 3 2 5 4 0 1 7 7 7 8 0 4 8 8 2 2 1 0 1 1 3 5 4 5 6
	  8 7 0 6 0 1 8 3 3 7 8 1 1 2 4 5 8 1 5 2 0 0 8 6 0 5 8 5 1 0
	  5 8 7 7 2 0 4 6 6 6 7 6 0 1 8 8 5 7 2 5 1 5 0 4 0
	 Decoded message: G0XYZ K1ABC FN42

     For the corresponding program jt65code only the information-carrying  chan-
     nel  symbols are shown, and the symbol values range from 0 to 63. Sync syn-
     bols lie two tone intervals below data tone 0, and the sequential locations
     of sync symbols are described in the JT65 Protocol section of this Guide.

     A typical execution of jt65code is shown below. The  program  displays  the
     packed message of 72 bits, shown here as 12 six-bit symbol values, followed
     by the channel symbols:

	 $ jt65code "G0XYZ K1ABC FN42"
	 Message:   G0XYZ K1ABC FN42
	 Packed message, 6-bit symbols:  61 36 45 30  3 55  3  2 14  5 33 40
	 Information-carrying channel symbols:
	    56 40  8 40 51 47 50 34 44 53 22 53 28 31 13 60 46	2 14 58 43
	    41 58 35  8 35  3 24  1 21 41 43  0 25 54  9 41 54	7 25 21  9
	    62 59  7 43 31 21 57 13 59 41 17 49 19 54 21 39 33 42 18  2 60
	 Decoded message: G0XYZ K1ABC FN42

     For an illustration of the power of the strong error-control coding in JT9,
     JT65  and	JT4,  try looking at the channel symbols after changing a single
     character in the message. For example, change the grid locater from FN42 to
     FN43 in the JT65 message:

	 $ jt65code "G0XYZ K1ABC FN43"
	 Message:   G0XYZ K1ABC FN43
	 Packed message, 6-bit symbols:  61 36 45 30  3 55  3  2 14  5 33 41
	 Information-carrying channel symbols:
	    25 35 47  8 13  9 61 40 44	9 51  6  8 40 38 34  8	2 21 23 30
	    51 32 56 39 35  3 50 48 30	8  5 40 18 54  9 24 30 26 61 23 11
	     3 59  7  7 39  1 25 24  4 50 17 49 52 19 34  7  4 34 61  2 61
	 Decoded message: G0XYZ K1ABC FN43

     You will discover that every possible JT65 message differs from every other
     possible JT65 message in at least 52 of the 63 information-carrying channel
     symbols.

	 $ qra64code "G0XYZ K1ABC FN43"
	      Message		      Decoded		     Err? Type
	 --------------------------------------------------------------------------
	    1 G0XYZ K1ABC FN43	      G0XYZ K1ABC FN43		  1:	Std Msg

	 Packed message, 6-bit symbols	61 36 45 30  3 55  3  2 14  5 33 41

	 Information-carrying channel symbols
	    61 36 45 30  3 55  3  2 14	5 33 41 14 28  2  7 58 45  9 43 20 48 29 55 43 24  3 13 18 21
	    40	3 17 28 59 62  2 50 26 24  2  1  2 61 10  9 16 40  1 18 28 30 33 39 60 45 16 21 60 11
	     9 40 14

	 Channel symbols including sync
	    20 50 60  0 40 10 30 61 36 45 30  3 55  3  2 14  5 33 41 14 28  2  7 58 45	9 43 20 48 29
	    55 43 24  3 13 18 21 40  3 20 50 60  0 40 10 30 17 28 59 62  2 50 26 24  2	1  2 61 10  9
	    16 40  1 18 28 30 33 39 60 45 16 21 60 11  9 40 14 20 50 60  0 40 10 30

	 $ msk144code "G0XYZ K1ABC FN43"
	     Message				   Decoded			       Err i3.n3
	 ----------------------------------------------------------------------------------------------------
	  1. G0XYZ K1ABC FN43			   G0XYZ K1ABC FN43			    1.	Standard msg

	 Channel symbols
	 110000110100110001010010011100110010010110000011011001001100001101111010
	 110010110111111100001101001111000111101011111011100001110000011101110110

	 $ ft8code "G0XYZ K1ABC FN43"
	     Message				   Decoded			       Err i3.n3
	 ----------------------------------------------------------------------------------------------------
	  1. G0XYZ K1ABC FN43			   G0XYZ K1ABC FN43			    1.	Standard msg

	 Source-encoded message, 77 bits:
	 00001000111111010001110111010000010011011110111100011010100010100001100111001

	 14-bit CRC:
	 00110001001011

	 83 Parity bits:
	 10000110000001010101100000100110100110100000111000101110000110001001110000000110011

	 Channel symbols (79 tones):
	   Sync 	      Data		 Sync		    Data	       Sync
	 3140652 03174526450547670460602143205 3140652 64040136505454507064041140042 3140652

     WSJT-X home page
	 https://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html

     WSJT-X User's Guide
	 https://www.physics.princeton.edu/pul-
	 sar/K1JT/wsjtx-doc/wsjtx-main-2.7.0-rc7.html

AUTHOR
     Joe Taylor, K1JT.

COPYING
     jt65code, jt9code, jt4code, and ft8code are Copyright (C) 2001  -	2020  by
     Joseph  H.  Taylor,  Jr., K1JT, with contributions from additional authors.
     WSJT-X is Open Source software, licensed under the GNU General  Public  Li-
     cense (GPLv3).

     These  programs  are  distributed in the hope that they will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of  MERCHANTABILITY
     or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
     more details.

AsciiDoc 2.7.0-rc7		   08/04/2026			     JT65CODE(1)

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