I traveled up to exit 176 today from exit 44 on I-95 here in NC. As soon as I reached the I-40 over pass (exit 81) I started getting K-band alerts. It took me a while to figure out just what was going on as this is one place that the LEO's sit and wait in three's and fours for someone to come flying by. Anyway as I reached the 102 exit I noticed that ever other overpass had a drone with a solar panel strapped to the support column. There must be 30 or 40 of these alone I-95 now. Sure does keep one on his toes.
The biggest key to these drones are the time intervals. They go off about ever 10 seconds and can be picked up a couple of miles away.