He got to work that morning. In the shed, piled among the old CRTs and CPUs and plasmas and bins of cell phones and Blu-rays, was an old stereo receiver—just AM and FM bands, but he could open that up—and an oscilloscope. A copper wire up the chimney served as their antenna; Michael refitted the guts of the receiver into a plain CPU chassis, to camouflage it—the only person who might have noticed an extra CPU sitting on the counter would be Gabe, and from what Sara had told him, the poor guy wasn’t ever coming back—and jacked the receiver into the panel, using the audio port. The battery control system had a simple media program, and with a little work he was able to configure the equalizer to filter out the battery noise. They wouldn’t be able to broadcast; he had no transmitter and would have to figure out how to build one from the bottom up. But for the time being, with a little patience, he’d be able to scoop out any decent signal from the west.

They found nothing.

Oh, there was plenty to hear out there. A surprising range of activity, from ULF to microwaves. The odd cell phone tower powered by a working solar panel. Geothermals still pushing juice back into the grid. Even a couple of satellites, still in their orbits, dutifully transmitting their cosmic hellos and probably wondering where everybody on planet Earth had run off to.

A whole hidden world of electronic noise. And nobody, not one single person, home.

Day by day, Elton would sit at the radio, the headphones clamped to his ears, his sightless eyes turned upward in their sockets. Michael would isolate a signal, clear out the noise, and send it to the amplifier, where it would be filtered a second time and pushed through the phones. After a moment of intense concentration, Elton would nod, maybe take a moment to give his crumby beard a thoughtful rub, and then proclaim, in his gentle voice:

“Something faint, irregular. Maybe an old distress beacon.”

Or: “A ground signal. A mine, maybe.”

Or, with a tight shake of the head: “Nothing here. Let’s move on.”

So they sat through the days and nights, Michael at the CRT, Elton with the earphones clamped to the sides of his head, his mind seemingly adrift in the leftover signals of their all-but-vanished species. Whenever they found one, Michael would record it in the logbook, noting the time and frequency and anything else about it. Then they’d do it all again.