Radium wrote:
Couldn't the Spin Exchange Relaxation Free Magnetometer receive the
magnetic portions of AM radio waves at the carrier frequencies I
described? If not, why?

Agreed, static magnetic fields tend to decay rapidly as you move away
from them. However, alternating magnetic fields continue to propogate
by generating alternating electric fields of the same frequency. These
alternating electric fields, in turn, generate alternating magnetic
fields. The cycle keeps repeating.

This thread reminds me of situations where someone acquire a little
knowledge of something and extrapolates it into areas of which they have an
limited skill set for understanding them.

Also reminds me of explaining things to my mother...but we won't go there.