Understanding the POCSAG paging protocol:
https://habr.com/en/post/438906/
It is possible to use SDR to decode the protocol:
$ rtl_fm -M fm -l 50 -s 22050 -f 929.938M | multimon-ng -t raw -a FLEX -a POCSAG512 -a POCSAG1200 -a POCSAG2400 -f alpha /dev/stdin
Source: https://www.reddit.com/r/RTLSDR/comments/423mpv/known_used_pocsagflex_pager_frequencies_in_houston/
