Swap the city perspective for the raw reality of the desert: vast and quiet, devoid of FM radio and cell phone coverage. I often traverse the vast, signal-spar

Swap the city perspective for the raw reality of the desert: vast and quiet, devoid of FM radio and cell phone coverage. I often traverse the vast, signal-sparse landscapes of the western US desert. These stretches are radio silence. FM? It makes it to the horizon (if it has maxed-out power). Cell and UHF? Line-of-sight. So, besides satellite radio, information far from a population center is only available from AM. While the effectiveness of many AM stations in fulfilling their public service obligations is debatable, that's a separate discussion.