Det spørs om vi kommer så langt i dette mysteriet her med å tenke tradisjonell elektronikk.
Noen "peer review scientific publications" de siste årene:
"A Method for Measuring the Characteristics of an EMI Suppression Ferrite Core", J. Uribe et al., IEEE Transactions on Electromagnetic Compatibility, Vol. 48, No. 4, November 2006.
Abstract: "Almost all digital equipment has electromagnetic interference (EMI) suppression ferrite cores to encircle cables, such as mains and peripheral cables. However, their EMI suppression capability is hardly evaluated from the impedance characteristics provided by the manufacturers. Hence, this paper proposes to characterize the ferrite core losses in terms of the insertion loss and the reflection coefficient."
"Analysis of Ferrite Beads For RF Isolation On Straight Wire Conductors", S. Saario et al., IEEE Electronics Letters, Vol. 33, No. 16, July 31, 1997.
Abstract: "Ferrite beads used for the suppression of electromagnetic interference (EMO) were analyzed using the finite difference time domain (FDTD) method. The presence of the bead results in reflected current, cable radiation and resonant characteristics which significantly affect the ability to suppress currents uniformly over a wide frequency range."
"Geometric Analysis and Manufacturing Considerations for Optimizing the Characteristics of a Twisted Pair", A. Lago, et al., IEEE Transactions on Electronics Packaging Manufacturing, Vol. 32, No. 1, January 2009.
Abstract: The geometry of a twisted pair largely determines its electrical characteristics. To improve and refine the value of these characteristics according to preset values, the optimization of the manufacturing process requires comprehensive knowledge of twisted pair geometry and of how electrical magnitudes are affected by the construction features of the twisted pair. This paper studies the relation between the length of a twisted pair cable and the length of each of the wires that compose the cable, by analyzing concepts such as pitch angle and radius of the helix."
"An Optimal New Shielded Twisted Pair Model to Improve the Electromagnetic Immunity in the Automotive Applications", C. M. Penlaver et al., 2007 IEEE International Symposium on Industrial Electronics, June 2007, Vigo, Spain.
Abstract: "Shielding twisted pair with metallic tape is a widely used resource to reduce the electromagnetic emissions and increase noise immunity of the twisted pair to those emissions. But, in addition to decrease electromagnetic emissions, shield also affects electric and geometry characteristics of the pair. Estimation of twisted pair geometry is vital to compute as much as the shield affects the electric characteristics of the pair. The goal of this paper is to develop a model of shielded twisted pair which allows to compute the shield shape as a function of twisted properties of the pair and physical characteristics of the shield tape. The model calculated in this paper is a part of a large work research; with the results of that research we can calculate the most used electric characteristics of the pair according to the physical and geometrical characteristics of it. This research was applied in an important cable manufacturing company of the automotive sector."
From Section II of the Penalver paper: "Electric characteristics of twisted pair depend on its physical and geometric characteristics, like number of twists per meter and dielectric characteristics of insulation or gap between cables in the pair. If twisted pair is covered by a shield, electric characteristics will be affected."