Scaled and Normalised Duals
In a real design situation it is usually desired to find the dual of an impedance with respect to some nominal or characteristic impedance. To do this, Z and Z' are scaled to the nominal impedance Z0 so that;
Z0 is usually taken to be a purely real number R0, so Z' is only changed by a real factor of R02. In other words, the dual remains qualitatively the same circuit but all the component values must be scaled quantitively by R02.
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