I found that increasing the number of segments had a significant change
in the input Z. The material I read on 5/8 antennas indicated the real
part of the Z was near 50 ohms. I could not get that result until I
increased the number of segments. Guess it is cause 146 MHZ antennas
are a good bit shorter than 3.5 MHZ antennas, and any small deviation
such as lenght, or # of segments will change the end results.
Gary N4AST