Despite covering a majority of central Alabama over-the-air, WDBB only provided Grade B coverage (at best) within Birmingham proper, even though Bessemer is located only southwest of the city. Due to the eastward location of its transmitter tower, WNAL's signal did not penetrate well into Birmingham either, only reaching as far west as extreme eastern Jefferson County. As a result, several major cable providers in the Birmingham market, including those serving Jefferson and Shelby counties, refused to carry the station. Ultimately, after all of DuBose's efforts to increase WDBB/WNAL's cable footprint failed, Fox signed an agreement to make WTTO its new Birmingham affiliate and moved its programming to channel 21 in January 1991.