To add to what Ace said, you generally just pivot the radio physically
on its axis to "null" any noise or interference. So, if the radio is
sitting on a table, pivoting the radio left or right should reduce
interference. Might seem silly, but it really does work. Ferrite rods
almost never move inside the radio.

I do have an old '70s Pioneer stereo hi-fi receiver with an _external_
ferrite AM antenna that does move and pivot, however.

FWIW, I don't know if it's still available, but I have an AM loop
antenna I bought from Radio Shack about five years ago that does a good
job in enhancing AM (MW) signals with almost any radio. It works quite
well with my Satellit 800.