More information about my disconnect problem.
Today after flying normally for about 10 minutes, suddenly the Evo is disconnected from my RC/Smart phone. I have no control over the Evo at all. It was within range and I did not have any prior warning (e.g. signal is weak). Evo came back and landed.
I switched to another battery. After 3 minutes it is suddenly disconnected. It flew back but hover over the landing spot refusing to land. I took a picture with my RC in the foreground. I waited until the battery run down to 15% and it finally landed.
Then I switched to my third battery. After 3 mintues it did the same thing. This time it came back and landed.
So the problem is definitely not with my batteries. It is either with the drone, or with my RC. I had the 4Hawks SR installed professionally by Covert Drones. I just wrote to Luke to see if he had seen this, and whether the 4Hawks is the culprit. Btw, 4Hawks works really well and I can go out 3+miles in urban area with any signal breakup.
So I am done with Evo for a while at least. Have to go back to Mavic Pro, until this problem is fixed. I love my Evo, but cannot fly it without any RC control.