I have an air core inductor.
Since its magnetic field will be large, and it will turn on and off rapidly, I assume it will make a lot of noise.
I don't want that noise to disturb the PCB's nearby, so I want to encase the inductor in mu metal.
Here is my question:
I don't want the magnetic field inside the inductor to change noticeably. Magnitude and direction should be unchanged inside the bore of the coil. (A 1% change is tolerable, but less is better.) How far away does mu metal need to be from the coil?