After the apocalypse, your big, fancy television will be dead--no power, no TV. So loot the corpse and use its parts to build the original broadcast entertainment: radio.

A radio transmitter sends information across a room, or an ocean, by creating a carrier wave of alternating current. Modulating the amplitude, or height, of that wave with an electrical signal (like the one produced by a microphone) encodes sound. Amplitude modulation (AM) was the first radio broadcast method and is still in wide use.

To pick up radio waves, I needed a receiver to isolate the signal representing audio. I built a simple crystal radio from a hulking Zenith television I found on the street. First, the radio required an antenna--the larger, the better--so I harvested wire from the TV and ran it up two flights of stairs, out the window, and down the side of the building.

Next, I built a tuned circuit to match the frequency of the carrier wave from any given station. I coiled magnet wire from the Zenith's shielding shroud around a nonconducting center, a.k.a. a beer bottle. Then, I sanded conductive points along the coil and rigged a movable connector. By changing contact points, I could change the length of the coil until I matched the desired frequency.