siglevdetcal - The SvxLink signal level detector calibration utility

       Tobias Blomberg (SM0SVX) <sm0svx at svxlink dot org>

siglevdetcal  is the SvxLink signal level detector calibration utility. It is used to assist in the setup
       of the SIGLEV_SLOPE and SIGLEV_OFFSET configuration variables for a  local  receiver.  The  signal  level
       detector need to be calibrated if a voter or the SIGLEV squelch detector is going to be used.

       The  calibration  procedure  is  quite  simple  and everything is more or less explained at run-time. The
       procedure is outlined below.

              • Disconnect the antenna and the PTT cable.  The  PTT  might  be  triggered  by  the  siglevdetcal
                utility.  If  you  want to be really sure that no harm come to your transceiver, connect a dummy
                load.

              • Setup the audio input level. The audio input level must not be changed after the calibration has
                been done.

              • Start the siglevdetcal utility.

              • Transmit on another radio so that the  receiver  under  calibration  will  receive  full  signal
                strength.

              • Still  holding the PTT, press ENTER and wait until the squelch open level measurements have been
                done.

              • Release the PTT. Make sure the squelch is open so that only noise is received.

              • Press ENTER to start the squelch close level measurements.

              • When finished, the two config variables SIGLEV_SLOPE and SIGLEV_OFFSET are printed. Put these in
                your configuration file under the corresponding receiver configuration section.

              • Start the SvxLink server and verify that full signal strength is showed as about  100  and  open
                squelch  is  showed  as  about 0. If full signal strength is not showed, you might have to setup
                SQL_DELAY to delay the signal level measurement until the signal is stable.

       ASYNC_AUDIO_NOTRIGGER
              Set this environment variable to 1 if you get an error about ioctl:Brokenpipe when the remotetrx
              server starts.

       ASYNC_AUDIO_ALSA_ZEROFILL
              Set this environment variable to 0 to stop the Alsa audio code from writing  zeros  to  the  audio
              device  when  there is no audio to write available.  ASYNC_AUDIO_UDP_ZEROFILL Set this environment
              variable to 1 to enable the UDP audio code to write zeros to the UDP connection when there  is  no
              audio to write available.

       siglevdetcal - The SvxLink signal level detector calibration utility

       Bugs should be reported using the issue tracker at https://github.com/sm0svx/svxlink.

       Questions  about  SvxLink  should  not be asked using the issue tracker. Instead use the group set up for
       this purpose at groups.io: https://groups.io/g/svxlink

svxlink(1), remotetrx(1), svxlink.conf(5)

Linux                                              AUGUST 2021                                   SIGLEVDETCAL(1)

siglevdetcal<configurationfile><RXconfigsectionname>