The lower signal strength at night might not be caused by lower signal, but dropped bits probably caused by skip. When I lived in Blytheville, I regularly picked up stations from Mo, Ky, Ms, La, and Ar at night. Check the analog channels when you see the signal drop off, and see if you are picking up skip. I live on a hilltop in North Little Rock, but have a 200' higher ridge to my east, and still pick up Memphis 52-1 occasionally off the back of my antenna. Wish I could afford about a 120' tower, I would really love to get the antenna up there. At my old location, I could watch Memphis stations from about 5pm to about 11am the next morning.