Sense
Magnetoception (or magnetoreception) is the ability to detect the direction one is facing based on the Earth's magnetic field. Directional awareness is most commonly observed in birds, which rely on their magnetic sense to navigate during migration. It has also been observed in insects such as bees. Cattle make use of magnetoception to align themselves in a north-south direction. Magnetotactic bacteria build miniature magnets inside themselves and use them to determine their orientation relative to the Earth's magnetic field.
Amelia Earhart
It is unknown whether the model 20B receiver had a beat frequency oscillator that would enable the detection of continuous wave transmissions such as Morse code and radiolocation beacons. Neither Earhart nor Noonan were capable of using Morse code. They relied on voice communications. Manning, who was on the first world flight attempt but not the second, was skilled at Morse and had acquired an FCC aircraft radiotelegraph license for 15 words per minute in March 1937, just prior to the start of the first flight.