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

NAME
       jt65code, jt9code, jt4code - Weak signal	communications encoding
       support utility.

SYNOPSIS
       jt65code	"MESSAGE"

       jt65code	[OPTIONS]

       jt9code "MESSAGE"

       jt9code [OPTIONS]

       jt4code "MESSAGE"

       jt4code [OPTIONS]

OPTIONS
       -t
	   Prints a selection of messages alongside their corresponding
	   decoded form	and types.

DESCRIPTION
       jt65code, jt9code and jt4code 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.

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

       WSJT-X User's Guide
	   http://www.physics.princeton.edu/pulsar/K1JT/wsjtx-doc/wsjtx-main-2.1.2.html

AUTHOR
       Joe Taylor, K1JT.

COPYING
       jt65code, jt9code and jt4code are Copyright (C) 2001 - 2015 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 2.1.2			  08/31/2020			   JT65CODE(1)

NAME | SYNOPSIS | OPTIONS | DESCRIPTION | AUTHOR | COPYING

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