:doctype: manpage :man source: AsciiDoc :man version: {revnumber} :man manual: WSJT-X Manual = jt65code(1) == NAME jt65code, jt9code - Weak signal communications encoding support utility. == SYNOPSIS *jt65code* MESSAGE *jt9code* MESSAGE == DESCRIPTION *jt65code* and *jt9code* 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. 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 and JT65, 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.html == OPTIONS == FILES == AUTHOR Joe Taylor, K1JT. == COPYING *jt65code* and *jt9code* are Copyright (C) 2001 - 2014 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.