1JT65CODE(1) WSJT-X Manual JT65CODE(1)
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6 jt65code, jt9code, jt4code, qra64code, ft8code, msk144code - Weak
7 signal communications encoding support utilities.
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10 jt65code "MESSAGE"
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12 jt65code [OPTIONS]
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14 jt9code "MESSAGE"
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16 jt9code [OPTIONS]
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18 jt4code "MESSAGE"
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20 jt4code [OPTIONS]
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22 qra64code "MESSAGE"
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24 qra64code [OPTIONS]
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26 ft8code "MESSAGE"
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28 ft8code [OPTIONS]
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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
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36 -T
37 As -T but for ft8code prints long format messages.
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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.
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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:
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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
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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.
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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:
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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
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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:
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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
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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.
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97 $ qra64code "G0XYZ K1ABC FN43"
98 Message Decoded Err? Type
99 --------------------------------------------------------------------------
100 1 G0XYZ K1ABC FN43 G0XYZ K1ABC FN43 1: Std Msg
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102 Packed message, 6-bit symbols 61 36 45 30 3 55 3 2 14 5 33 41
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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
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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
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114 $ msk144code "G0XYZ K1ABC FN43"
115 Message Decoded Err i3.n3
116 ----------------------------------------------------------------------------------------------------
117 1. G0XYZ K1ABC FN43 G0XYZ K1ABC FN43 1. Standard msg
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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
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128 Source-encoded message, 77 bits:
129 00001000111111010001110111010000010011011110111100011010100010100001100111001
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131 14-bit CRC:
132 00110001001011
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134 83 Parity bits:
135 10000110000001010101100000100110100110100000111000101110000110001001110000000110011
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137 Channel symbols (79 tones):
138 Sync Data Sync Data Sync
139 3140652 03174526450547670460602143205 3140652 64040136505454507064041140042 3140652
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141 WSJT-X home page
142 https://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html
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144 WSJT-X User’s Guide
145 https://www.physics.princeton.edu/pulsar/K1JT/wsjtx-doc/wsjtx-main-2.5.4.html
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148 Joe Taylor, K1JT.
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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).
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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)