This project will have all my gnuradio grc files
Here is my files for rtl-sdr Lime sdr and hackrf
If you want a radio design for your application then contact me.
If you want to decode afsk you need to install https://github.com/dl1ksv/gr-ax25
Restart gnuradio-companion
compile detectmarkspace.grc
close gnuradio-companion
Start gnuradio-companion and open the exsample APRS.grc
your afsk decoder should now work
run the following command if ou upgrade or downgrade from previose verion of gnuradio before starting gnuradio 3.8 to .3.9
rm -rf ~/.cache/grc_gnuradio/cache.json