======  📺  Live du 24 septembre 2022 : Découverte de RTLSDR-AIRBAND (2) ======

Replay : https://www.twitch.tv/videos/1934217438

===== Programme =====

  * Accueil
  * Poursuivre la découverte de ''rtlsdr_airband''

===== ⚙️ Ce qu'on a fait =====

  * Modifier le fichier de config de rtlsdr_airband 
    * pour lui faire scanner les 16 canaux PMR446
    * pour lui faire envoyer le flux audio vers un serveur IceCast
  * Écouter le flux audio sur VLC
  * Transmettre dans un talkie-walkie PMR446 pour contrôler qu'on reçoit et qu'on peut entendre le signal dans VLC (et ça fonctionne ! 🙌 )
  * Modifier à nouveau le fichier de config de rtlsdr_airband :
    * pour lui faire écouter simultanément les 16 canaux PMR446
    * envoyer les 16 flux audio des 16 canaux vers 16 points de montage distincts sur le serveur IceCast
  * On a écouté le flux audio sur VLC et on a fait quelques tests avec le talkie-walkie PMR446
  * Enfin, dernière modification du fichier de config de rtlsdr_airband pour :
    * monitorer la fréquence APRS de la Station Spatiale Internationale (145.825 MHz) sous deux formes :
      * un flux audio IceCast
      * un flux audio encapsulé dans de l'UDP
  * On a guetté le passage d'ISS avec un logiciel de poursuite satellite : GPredict
  * On a tenté d'écouter les trames APRS de l'ISS (hélas sans succès)
  * On a tenté de décoder les trames APRS de l'ISS (sans succès puisqu'aucune réception)
  * On a tenté vite-fait d'écouter la fréquence phonie UHF de l'ISS (437.800 MHz)
  * Enfin on a refait quelques tests de décodage APRS (AX.25) à partir du tracker AVRT5


===== 📄 Les fichiers de conf de rtlsdr-airband qu'on a utilisés =====

==== 🔴 Scanner les 16 canaux PMR446 ====
...et diffuser le résultat sur un seul ''mountpoint'' du serveur ICEcast

<code bash>
#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
# Global configuration
#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
fft_size = 256;
multiple_demod_threads = false;
multiple_output_threads = false;
# log_scan_activity = true;
# stats_filepath = "/media/airprophet/logs/rtl_airband_stats.txt";

#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
# Hardware & Frequencies
#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
devices: (
  # RTL-SDR INDEX 0
  {
    type = "rtlsdr";
    index = 0;
    gain = 40.2;
    sample_rate = "1.28M";
    correction = 77;
    mode = "scan";
    channels: (
      {
        freqs = ( 446.00625, 446.01875, 446.03125, 446.04375, 446.05625, 446.06875, 446.08125, 446.09375, 446.10625, 446.11875, 446.13125, 446.14375, 446.15625, 446.16875, 446.18125, 446.19375 );
        labels = ( "PMR 01", "PMR 02", "PMR 03", "PMR 04", "PMR 05", "PMR 06", "PMR 07", "PMR 08", "PMR 09", "PMR 10", "PMR 11", "PMR 12", "PMR 13", "PMR 14", "PMR 15", "PMR 16" )
        modulation = "nfm";
        afc = 0;
        # notch = 100.0;
        # notch_q = 10.0;
        # squelch_threshold = -20;
        bandwidth = 15000;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446";
            name = "PMR446";
            description = "Scanning the 16 PMR446"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      }
    );
  }
);
</code>

==== 🔴 Diffuser les 16 canaux PMR446 ====
...sur 16 ''mountpoints'' différents tout en écoutant la fréquence APRS de l'ISS (145.825 MHz) et la fréquence APRS terrestre (144.800 MHz)

<code bash>
#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
# Hardware & Frequencies
#╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴╴
devices: (
  # RTL-SDR INDEX 0
  {
    type = "rtlsdr";
    index = 0;
    gain = 29.7;
    centerfreq = "145.3M";
    sample_rate = "1.28M";
    correction = 75;
    mode = "multichannel";
    channels:
    (
      {
        disable = false;
        freq = "145.825M";
        label = "APRS ISS"
        modulation = "nfm";
        squelch_snr_threshold = 0;
        bandwidth = 15000;
        outputs: (
          {
            type = "udp_stream";
            dest_address = "127.0.0.1";
            dest_port = 15825;
            continuous = true;
          },
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "aprs_iss";
            name = "APRS ISS";
            description = "Fréquence APRS de la Station Spaciale Internationale"
            genre = "APRS";
            username = "source";
            password = "PASSWORD";
          }
        );
      },
      {
        disable = false;
        freq = "144.8M";
        label = "APRS"
        modulation = "nfm";
        squelch_snr_threshold = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "udp_stream";
            dest_address = "127.0.0.1";
            dest_port = 14480;
            continuous = true;
          },
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "aprs_terrestre";
            name = "APRS TERRESTRE";
            description = "Fréquence APRS terrestre"
            genre = "APRS";
            username = "source";
            password = "PASSWORD";
          }

        );
      }
    );
  },

  # RTL-SDR INDEX 1
  {
    type = "rtlsdr";
    index = 1;
    gain = 40.2;
    sample_rate = "1.28M";
    centerfreq = "446.1M";
    correction = 36;
    mode = "multichannel";

    # ==========================================================================
    # CANAUX PMR446
    # ==========================================================================

    channels: (

      # ------------------------------------------------------------------------
      # PMR 01
      # ------------------------------------------------------------------------
      {
        freq = 446.00625;
        modulation = "nfm";
        lowpass = 3000;
        highpass = 300;
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch01";
            name = "PMR446 channel 01";
            description = "PMR446 channel 01"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        )
      },

      # ------------------------------------------------------------------------
      # PMR 02
      # ------------------------------------------------------------------------
      {
        freq = 446.01875;
        modulation = "nfm";
        lowpass = 3000;
        highpass = 300;
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch02";
            name = "PMR446 channel 02";
            description = "PMR446 channel 02"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 03
      # ------------------------------------------------------------------------
      {
        freq = 446.03125;
        modulation = "nfm";
        lowpass = 3000;
        highpass = 300;
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch03";
            name = "PMR446 channel 03";
            description = "PMR446 channel 03"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 04
      # ------------------------------------------------------------------------
      {
        freq = 446.04375;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch04";
            name = "PMR446 channel 04";
            description = "PMR446 channel 04"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 05
      # ------------------------------------------------------------------------
      {
        freq = 446.05625;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch05";
            name = "PMR446 channel 05";
            description = "PMR446 channel 05"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 06
      # ------------------------------------------------------------------------
      {
        freq = 446.06875;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch06";
            name = "PMR446 channel 06";
            description = "PMR446 channel 06"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 07
      # ------------------------------------------------------------------------
      {
        freq = 446.08125;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch07";
            name = "PMR446 channel 07";
            description = "PMR446 channel 07"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 08
      # ------------------------------------------------------------------------
      {
        freq = 446.09375;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch08";
            name = "PMR446 channel 08";
            description = "PMR446 channel 08"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 09
      # ------------------------------------------------------------------------
      {
        freq = 446.10625;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch09";
            name = "PMR446 channel 09";
            description = "PMR446 channel 09"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 10
      # ------------------------------------------------------------------------
      {
        freq = 446.11875;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch10";
            name = "PMR446 channel 10";
            description = "PMR446 channel 10"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 11
      # ------------------------------------------------------------------------
      {
        freq = 446.13125;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch11";
            name = "PMR446 channel 11";
            description = "PMR446 channel 11"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 12
      # ------------------------------------------------------------------------
      {
        freq = 446.14375;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch12";
            name = "PMR446 channel 12";
            description = "PMR446 channel 12"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 13
      # ------------------------------------------------------------------------
      {
        freq = 446.15625;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch13";
            name = "PMR446 channel 13";
            description = "PMR446 channel 13"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 14
      # ------------------------------------------------------------------------
      {
        freq = 446.16875;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch14";
            name = "PMR446 channel 14";
            description = "PMR446 channel 14"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 15
      # ------------------------------------------------------------------------
      {
        freq = 446.18125;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch15";
            name = "PMR446 channel 15";
            description = "PMR446 channel 15"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      },

      # ------------------------------------------------------------------------
      # PMR 16
      # ------------------------------------------------------------------------
      {
        freq = 446.19375;
        modulation = "nfm";
        afc = 0;
        bandwidth = 12500;
        outputs: (
          {
            type = "icecast";
            server = "radiocast.extramuros.com";
            port = 8002;
            mountpoint = "pmr446ch16";
            name = "PMR446 channel 16";
            description = "PMR446 channel 16"
            genre = "PMR446";
            username = "source";
            password = "PASSWORD";
          }
        );
      }
    );
  }
);

</code>
===== Liens Utiles =====

  * GPredict : http://gpredict.oz9aec.net/
  * L'activité radioamateur à bord de l'ISS : https://www.ariss.org/contact-the-iss.html