Here is one for your knowledge base. I lived next to the train tracks. I could hold a lead in each hand and get a millivolt reading. Fluctuated a little but was fairly stable as an average. But when an electric locomotive went by it at least doubled as the extra input I was getting as a capacitor as the locomotive went by. Rocks and boulders give readings, some with reverse polarity, some read higher than others on AC or DC. Just jam them in the dirt and you will get a substantial reading...
Yep... Meters are fun... :)
LOL... I’m 40 years into an Electronic Technician career. Wind, dust, clothes, almost anything moving generates a small electrical field. Article is pretty laughable. Yeah, they might be getting some magnetic pole indication. Might. But I would start by using some proper electronics.
Early 60s - Moses Lake Washington SAC base.
End of runway shack that had some kind of device that measured earth voltage (We may have been picking up timing signals from somewhere.)
We recorded earth voltage on a paper chart where we neutralized the DC component leaving the AC part detectable.
Curious about how senstive this was, it phoned the fella on night shift that I was going to try something - just watch the chart.
From the barracks about 2 miles away, I inserted two wires, bare ends in the ground, about 50 feet apart.
I then stuck a 9 V battery to the other two ends.
He replied the needle just pegged on the chart recorder.