Those antennas from Antennas Direct might work for you, but I believe they overestimate the gain you'll get from them, so you might be better off with the DB4.
I now use a
Winegard SquareShooter antenna. I mounted it in my attic. Do you have a balcony where you could mount this? The grey box shown in the photo is 16×16×4 inches, no bigger than a Direct TV dish. It does cost a bit more than the DB2 or 4, but it is compact and is easier on the eyes.
I live in the Washington, DC area where some local stations are 15-20 miles from my house, and stations in Baltimore are at least 40 miles away. I get all of them clearly. This antenna should work well for you if the Sears Tower is 26 miles from you.