[Southack]

"If it didn't get there at the speed of light, radar wouldn't work."

I don't see where you dug that statement up. I'm not arguing about the speed of *disturbances* in an existing electromagnetic field, but rather how fast a magnetic field covers an area.

[Physicist]

I'm not arguing about the speed of *disturbances* in an existing electromagnetic field, but rather how fast a magnetic field covers an area.

Oh, aye. And as the radar dish sweeps around, shining its beam on regions untouched by magnetic field, is this not the same thing as "turning on the field" there?