If you're on debian/ubuntu, you should be able to install "minimodem", which allows for this sort of thing with the usual wide variety of command-line parameter

If you're on debian/ubuntu, you should be able to install "minimodem", which allows for this sort of thing with the usual wide variety of command-line parameters. echo "hello hacker news" | minimodem --tx 110 yields a nice classical "telemetry" sound.