AM towers can broadcast more than one frequency at a time, but I'm not sure how common it is in practice. http://www.radioworld.com/article/four-am-stations-sh

AM towers can broadcast more than one frequency at a time, but I'm not sure how common it is in practice. http://www.radioworld.com/article/four-am-stations-sharing-one-site/220752 http://www.radioworld.com/article/four-am-stations-sharing-o...