No kidding _Jim bob. Whoever said that a magnetometer WOULD "see" a EM wave? What was said is that within arguably REAL crop circles, the magnetic field is ELEVATED in relation to the Earth's magnetic field. Apparently, the magnetic field abnomality follows the geometry of the formation.
As far as the EM irregularities, I'm not sure what they used to detect that phenomenon, but I'd guess that it was a spectrum analyzer...
(You really DON'T know your physics, do you?)
Why don't you tell me a little about the following equation and what it demonstrates...
B . dA = 0
Regards,
FL