Here is a simple way to Unipager-Audio transmit your callsign announcement, as required by law in many countries.

First, create a .wav file with the desired announcement. It can be CW or speech, on your choice:
  * To create a CW .wav file visit: http://www.meridianoutpost.com/resources/etools/calculators/calculator-morse-code.php
  * To create a voice .wav (in 17 different languages) visit: https://ttsmp3.com/
  * Convert the .mp3 to .wav (if needed) visit: https://online-audio-converter.com/
  * Rename your .wav file to "callsign.wav"

Once you have the wav file, login to Unipager OS host over SSH terminal (eg. Putty) and type the following commands:

  sudo -i
  mkdir /unipager
  chmod 777 /unipager
  cd /unipager
  touch callsign.sh
  nano callsign.sh

The nano editor will be openend, so paste the following content:

  #!/bin/bash
  # CALLSIGN SCRIPT
  sleep 30
  service unipager stop
  sleep 5
  echo 1 > /sys/class/gpio/gpio1/value
  sleep 1
  aplay /unipager/callsign.wav -D plughw:1
  echo 0 > /sys/class/gpio/gpio1/value
  service unipager restart

Press Ctrl-X, then press Y to save the content.

<color #ed1c24>IMPORTANT:</color> The "-D plughw:1" parameter is meant to systems using external USB soundcard. If using Raspberry native soundcard this parameter can be suppressed.
IMPORTANT: this script opens GPIO1 to act the PTT. Use the same GPIO declared on Unipager-Audio configuration.

Still on terminal type "crontab -e" to open the scheduler configuration, then add the following line to the end of file:

  */10 * * * * sudo /unipager/callsign.sh

Press Ctrl-X, then press Y to save the content.

Now find a way to transfer the callsign.wav file from your computer to the /unipager folder on unipager host, the easiest way is using WinScp software (or use wget, ftp, etc)

Type the command
  chmod 777 *

Type the command
  reboot now
  
<color #ed1c24>Beware that this solution only waits for 30 seconds to empty the UniPager queue. On cases with high traffic and/or only few available time slots this may lead to loss of messages!</color>

Manual by Renato [[https://www.qrz.com/db/pu2utr|PU2UTR]]