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Transfer along a linę

To find the input impedance of a linę of length I and characteristic impedance Zo terminated

in a load impedance Zi, we normaliseZi with respect to Zoto obtain zl, enter the Smith Chart at zl, move clockwise by an amount 2pl radians, and read off the normalised input impedance zinat the point resulting. The unnormalized input impedance

iS Zin= ZoZin.

To make such operations simple, the Smith Chart has a peripheral scalę graduated A, thus avoiding the need for conversion of linę lengths to radians. Notę that movement

of only half a wave length along a linę corresponds to movement of one fuli

revolution

around the chart.