The Locus of Points of Constant VSWR When Renormalized to a Different Characteristic Impedance (Letters)

The locus of points of constant VSWR with respect to an impedance Z/sub 1/, when measured with equipment of characteristic impedance Z/sub 0/, other than Z/sub 1/, is found to be a circle that is easily constructed on a Smith chart. The use of a transparent overlay with various such circles converts any network analyzer with a Smith chart display to read swept VSWR values to the new impedance.