I am using a Sensar RV 2500 antenna in a 5th wheel trailer. I have a digital television with its own digital tuner. When I run a scan, depending on the direction of the antenna, I get multiple channels, including network channels from Southwest Michigan and Northwest Indiana. The trouble is I have a perfect picture for a few minutes and then all of a sudden no signal. Then the picture will come back after a few seconds or few minutes. It keeps going back and forth until I give up, move the antenna again and rescan. The problem has occurred with channels from Battle Creek (CBS), Grand Rapids (NBC) and South Bend (NBC). If I aim the antenna toward Lake Michigan I also get stations from Chicago but have the same problem. This problem seems to be worse during daylight hours and not so bad evenings. Any suggestions will be appreciated.