All of the comments like these don’t understand the word emergency.
There are numerous plausible reasons cell phone towers, computers, and TV will be out in a true emergency.
I mean, hell, cell phone were unusable on 9/11 due to congestion, and even though it was a horrible event, it want an emergency the like of which are possible.
AM is dead fucking simple. Seriously. If you know what you’re doing, you can make a receiver with a wire, a resistor, and a speaker. You don’t even need power to run it.