His latest release, NEC4WIN95, makes use of many of the graphical and user-friendly facets of the operating system, and further developments are in the wind. Antenna modeling software begins with a geometry module, where the user enters in the coordinates of his or her straight-line model of the antenna. As the figure show, NEC4WIN95 uses a spreadsheet layout for key entries. Then it is a matter of filling in the X, Y, and Z values, along with the number of segments. These boxes make relatively easy work of modeling traps as well as standard reactive loads.
Additional boxes permit setting the frequency and ground parameters for the model.
As with every modeling program, users should thoroughly familiarize themselves with what each parameter means to the modeling process. Antennas are not just assemblies of copper or aluminum. They exist within a set of conditions, and the assembly and the conditions together determine in what way the antenna does its job. Although most antenna modeling programs produce only data tables out of their cores, commercial implementations rely heavily on graphical pattern plotting to aid users in understanding the potential performance of the antenna being modeled. Viewing the antenna has two main uses.