Alec in Atlanta has a portable radio to talk to Monroe in Philadelphia, who uses a base station. Portable radios only have a range of a few miles (less inside a building such as where Alec was), and depending upon the antenna and terrain base stations only have a range of under 100 miles. In order for him to talk to Monroe, his radio would have to work like a cellphone and go through a network of towers. Since there was no power between Philadelphia and Atlanta and they are about 760 miles apart, it would be impossible for the two to communicate as was shown.