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

6       jt65code, jt9code, jt4code, qra64code, ft8code, msk144code - Weak
7       signal communications encoding support utilities.
8

SYNOPSIS

10       jt65code "MESSAGE"
11
12       jt65code [OPTIONS]
13
14       jt9code "MESSAGE"
15
16       jt9code [OPTIONS]
17
18       jt4code "MESSAGE"
19
20       jt4code [OPTIONS]
21
22       qra64code "MESSAGE"
23
24       qra64code [OPTIONS]
25
26       ft8code "MESSAGE"
27
28       ft8code [OPTIONS]
29

OPTIONS

31       -t
32           Prints a selection of messages alongside their corresponding
33           decoded form and types. With ft8code prints a selection of short
34           format messages
35
36       -T
37           As -T but for ft8code prints long format messages.
38

DESCRIPTION

40       jt65code, jt9code, jt4code, and ft8code are utility programs that let
41       you explore the conversion of user-level messages into channel symbols
42       or “tone numbers.” These programs can be useful to someone designing a
43       beacon generator for JT9 or JT65, or for studying behavior of the
44       error-control codes for each of the protocols.
45
46       Channel-symbol values for JT9 run from 0 to 8, with 0 representing the
47       sync tone. The total number of symbols in a transmitted message is 85.
48       To run jt9code, enter the program name followed by a JT9 message
49       enclosed in quotes. In Windows the command and program output might
50       look like this:
51
52           $ jt9code "G0XYZ K1ABC FN42"
53           Message:   G0XYZ K1ABC FN42
54           Channel symbols:
55            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
56            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
57            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
58           Decoded message: G0XYZ K1ABC FN42
59
60       For the corresponding program jt65code only the information-carrying
61       channel symbols are shown, and the symbol values range from 0 to 63.
62       Sync synbols lie two tone intervals below data tone 0, and the
63       sequential locations of sync symbols are described in the JT65 Protocol
64       section of this Guide.
65
66       A typical execution of jt65code is shown below. The program displays
67       the packed message of 72 bits, shown here as 12 six-bit symbol values,
68       followed by the channel symbols:
69
70           $ jt65code "G0XYZ K1ABC FN42"
71           Message:   G0XYZ K1ABC FN42
72           Packed message, 6-bit symbols:  61 36 45 30  3 55  3  2 14  5 33 40
73           Information-carrying channel symbols:
74              56 40  8 40 51 47 50 34 44 53 22 53 28 31 13 60 46  2 14 58 43
75              41 58 35  8 35  3 24  1 21 41 43  0 25 54  9 41 54  7 25 21  9
76              62 59  7 43 31 21 57 13 59 41 17 49 19 54 21 39 33 42 18  2 60
77           Decoded message: G0XYZ K1ABC FN42
78
79       For an illustration of the power of the strong error-control coding in
80       JT9, JT65 and JT4, try looking at the channel symbols after changing a
81       single character in the message. For example, change the grid locater
82       from FN42 to FN43 in the JT65 message:
83
84           $ jt65code "G0XYZ K1ABC FN43"
85           Message:   G0XYZ K1ABC FN43
86           Packed message, 6-bit symbols:  61 36 45 30  3 55  3  2 14  5 33 41
87           Information-carrying channel symbols:
88              25 35 47  8 13  9 61 40 44  9 51  6  8 40 38 34  8  2 21 23 30
89              51 32 56 39 35  3 50 48 30  8  5 40 18 54  9 24 30 26 61 23 11
90               3 59  7  7 39  1 25 24  4 50 17 49 52 19 34  7  4 34 61  2 61
91           Decoded message: G0XYZ K1ABC FN43
92
93       You will discover that every possible JT65 message differs from every
94       other possible JT65 message in at least 52 of the 63
95       information-carrying channel symbols.
96
97           $ qra64code "G0XYZ K1ABC FN43"
98                Message                 Decoded                Err? Type
99           --------------------------------------------------------------------------
100              1 G0XYZ K1ABC FN43        G0XYZ K1ABC FN43            1:    Std Msg
101
102           Packed message, 6-bit symbols  61 36 45 30  3 55  3  2 14  5 33 41
103
104           Information-carrying channel symbols
105              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
106              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
107               9 40 14
108
109           Channel symbols including sync
110              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
111              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
112              16 40  1 18 28 30 33 39 60 45 16 21 60 11  9 40 14 20 50 60  0 40 10 30
113
114           $ msk144code "G0XYZ K1ABC FN43"
115               Message                               Decoded                             Err i3.n3
116           ----------------------------------------------------------------------------------------------------
117            1. G0XYZ K1ABC FN43                      G0XYZ K1ABC FN43                         1.  Standard msg
118
119           Channel symbols
120           110000110100110001010010011100110010010110000011011001001100001101111010
121           110010110111111100001101001111000111101011111011100001110000011101110110
122
123           $ ft8code "G0XYZ K1ABC FN43"
124               Message                               Decoded                             Err i3.n3
125           ----------------------------------------------------------------------------------------------------
126            1. G0XYZ K1ABC FN43                      G0XYZ K1ABC FN43                         1.  Standard msg
127
128           Source-encoded message, 77 bits:
129           00001000111111010001110111010000010011011110111100011010100010100001100111001
130
131           14-bit CRC:
132           00110001001011
133
134           83 Parity bits:
135           10000110000001010101100000100110100110100000111000101110000110001001110000000110011
136
137           Channel symbols (79 tones):
138             Sync               Data               Sync               Data               Sync
139           3140652 03174526450547670460602143205 3140652 64040136505454507064041140042 3140652
140
141       WSJT-X home page
142           https://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html
143
144       WSJT-X User’s Guide
145           https://www.physics.princeton.edu/pulsar/K1JT/wsjtx-doc/wsjtx-main-2.5.4.html
146

AUTHOR

148       Joe Taylor, K1JT.
149

COPYING

151       jt65code, jt9code, jt4code, and ft8code are Copyright © 2001 - 2020 by
152       Joseph H. Taylor, Jr., K1JT, with contributions from additional
153       authors. WSJT-X is Open Source software, licensed under the GNU General
154       Public License (GPLv3).
155
156       These programs are distributed in the hope that they will be useful,
157       but WITHOUT ANY WARRANTY; without even the implied warranty of
158       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
159       General Public License for more details.
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163AsciiDoc 2.5.4                    01/22/2022                       JT65CODE(1)
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