
195Smith Chart
• As the normalised x may assume positive or negative values, the
centres of constant x circles will gradually move away from p = 1,
q = 0.
• The movement of centres along the q axis will be in the direction
opposite to the sign of x.
• The centre of the largest constant x circle will lie at p = 1, q = ± ∞ with
innite radius and will correspond to x = 0.
• The centres of smallest constant x circles will lie at p = 1, q = 0 with
zero radius and will correspond to x = ∞.
• All impedances on the outermost (r = 0) circle are purely reactive
ranging from 0 to ±∞.
• This agrees that for pure reactance (i.e. at the