And you make the changes the program magic, then connect the drone to your phone, start the DJI to go, and then re-connect the remote to your computer, turn on the magic button and click iwinfo and see the result. In general, following a decision problem, you need to add the following lines to the end of the file, etc/Init.d/rcS for telnet, everything you do, you do at your own risk. I propose to do in version 5.3 also add this script to solve the problem
echo '* * * * * if [ `/usr/sbin/iw reg get | sed -n 1p | cut -c9-10`!=US ]; then /usr/sbin/iw reg set US; fi' > /etc/crontabs/root
mkdir -p /var/spool/cron
ln -s /var/spool/cron/crontabs /etc/crontabs
/usr/sbin/crond