The EM-2108 is a standard test fixture for evaluation of the electromagnetic shielding effectiveness (SE) of planar materials. The fixture is a section of coaxial transmission line broken to allow the insertion of planar test materials. Although ASTM D4935-10 is currently limited to an upper frequency of 1.5 GHz, the EM-2108 meets and complies fully with both the impedance and SE requirements called out in ASTM test method D4935-10 up to 10 GHz. These results are shown in Figures 1 & 2. The measured data relates to the shielding effectiveness due to a plane wave (far field EM wave) from which near field values for magnetic and electric fields may be inferred.
The EM-2108 is provided with a reference standard test specimen, a load standard test specimen, and a dynamic range specimen. Dynamic range of greater than 80 dB is achievable, although the cables and other test system components usually establish the limiting factors.