Is the compass incorrect because of something magnetic or because the earths magnetic field is being distorted?
Heres why the meter supplied with the degausser is important: With the compass you are trying to measure the earth’s magnetic field and not the magnetic field of your aircraft. This meter is not sensitive enough to react to the earths magnetic field so any meter movement is the result of something being magnetized that shouldn’t be. If there is no movement with the meter then your compass error may be caused by the earths magnetic field inducing a magnetic field in nearby iron objects. A magnetic field is the vectored sum of all the fields present at any point. This means that the earths field traveling one direction through air acts on the compass and; The earths field induces magnetism in a nearby iron structure that also acts on the compass. The sum of the two fields vectors is where the compass points. You cannot remove the earth field from the iron structure as you cannot degauss the earth. Youre choices are to move the compass, move the iron structure, or use compensating magnets
