The electromagnetic shielding characteristics of four fabricsamples made from metal clad aramid yarn and nickel plated copper wirewere measured from 1 kHz to 3 GHz. Below 100 kHz, these measurementsshowed that the surface transfer impedance or surface resistivity rangedfrom 0.5 mΩ/square to 1.3 mΩ/square. This is extremely good.In this frequency range, the current flows on the wires. Between 10 and100 MHz, the mid-frequency or limiting shielding effectiveness wasgreater than 70 dB. At 100 MHz and above, all samples were essentiallyequal at 45 mΩ/square. In this frequency range the current spreadsacross the fabric. A diffusion cut-off frequency was not observed in anyof the samples
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