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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 messages

       -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 generator	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
       channel symbols are shown, and the symbol values	range from 0 to	63.
       Sync synbols 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/pulsar/K1JT/wsjtx-doc/wsjtx-main-2.3.0.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 License (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 2.3.0			  12/18/2021			   JT65CODE(1)

NAME | SYNOPSIS | OPTIONS | DESCRIPTION | AUTHOR | COPYING

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