has the advantage of a high permeability and low magnetic remanence and eliminates problems that would otherwise occur due to magnetic interaction.
Materials used to shield EMI signals are ferromagnetic metals with high permeability that can range from low cost steels to highly tailored mumetal (a special alloy with extremely high permeability).
Ferromagnetic coatings with nanocrystalline grain size offer permeability close to that of mumetals but do not need to be annealed.
The "AA" Series can be PCB or chassis mounted in the standard plastic package or outfitted with optional mumetal
To achieve the acceptable levels, the engineering team covered the floor and all four walls with a specially created multilayer, three-substrate shield of welded aluminum plates and multiple layers of silicon-iron and mumetal
Fabricated from MuMETAL
alloy, the chamber reduces ambient magnetic fields and the earth's geomagnetic field (0.25 to 0.65 Gauss) to the milliGauss level.
National can deep draw custom enclosures to specifications in every drawable material, including ferrous and nonferrous, titanium, hasteloy, nickel, kovar, inconel, mumetal
, monel, and tantalum.