wrong naming of port impedance fixed
@@ -47,7 +47,7 @@ class RectangularWaveguide(Media):
z0 : number, array-like, or None
the port impedance for media. Only needed if its different
from the characterisitc impedance of the transmission
- line. if z0 is None then will default to z0
+ line. if z0 is None then will default to Z0.
a : number
width of waveguide, in meters.
b : number
