Marauder Scanning
The data the listening station was passing on had to be going out via a highly-directional microwave or laser transmission. If it was microwave, there would be a certain amount of directional leakage. If it was laser, then it should leave a faint but detectable trace where it reflected off specks of dust in the air—like a flashlight beam through smoke. Either way, we would pick it up when we were near enough. All we had to do was drive back and forth while the sensors kept an eye out.
(Of course, it could also be going through the Internet, but our hackers had found that the only area connections using enough bandwidth were all movie torrenters.)
After the first few hours, it began to get dull. I shoved the steering wheel across to the passenger side, pulled the keyboard out from under the dash, and flipped the multifunction display over to data terminal mode. Since Tasha was doing all the work, I figured I might as well just surf for a while.
I didn’t expect to find another piece of the puzzle.