A simple VOR receiver git the radial in degree from the VOR.
vortrack [-g gain] [-l interval ] [-r device] frequency (in Mhz)
-l interval : interval in second between two measurements
-g gain in tens of db (ie : -g 400 )
-p ppm : ppm freq shift
-r n : rtl device number (mandatory for rtl sdr)
vortrack 109.25
airwav depends of usb lib and rtlsdr or airspy lib
For rtl sdr :
make -f Makefile.rtl
for airspy :
make -f Makefile.airspy