My lease is in the middle of Harmon County, OK (north of Hollis) with very poor cell service, even on top of a hill. My camera is definitely not in a good spot and couldn't get any reception with the external antennae Covert sells almost 15ft in the air. I tried this Yagi directional antennae from Amazon Yagi antennae link
on a 15ft piece of 1.5" Sched. 40 PVC and got 2 bars! Pay attention to the cables and genders when making your connections.