" That was a self defeating test. The idea here is that you will have a
lower noise floor in a locally noisy area with a shielded loop than a
dipole antenna. There is going to be no advantage to using a loop over
a dipole in an electrically quiet area.
A shielded loop is not better at picking up a distant signal than a
dipole but is less sensitive to local noise generators so in an area
with high local noise you would have better signal to noise than a
full size dipole antenna.
Please see:
http://www.w8ji.com/magnetic_receiving_loops.htm
Dale W4OP