EZNEC

EZNEC plots azimuth and elevation patterns; tells you gain, feedpoint impedance, SWR, and current distribution; finds and reports beamwidth, 3-dB pattern points, f/b ratio, takeoff angle, sidelobe characteristics; and more. All information, including patterns, can be displayed on screen or printed on any Windows compatible printer. And its easy to use with EZNECs menu structure, spreadsheet-like entry, and many shortcut features.
You describe the antenna (and other nearby structures if desired) as a group of straight conductors, choosing the orientation, length, and diameter. Add sources at the feedpoints and, if desired, transmission lines, a realistic ground, and loads to simulate loading coils, traps, or similar components. Using this description method, you can quickly analyze Yagis, quads, phased arrays, towers, loops -- nearly any type of antenna or parasitic structure.
Antenna descriptions and pattern plots are easily saved and recalled for future analysis. Multiple patterns can be superimposed on a single graph for comparison. See the pattern and antenna currents on the same color 3-D display as the antenna. Rotate the antenna display and zoom in for details.
EZNEC features an innovative 3D pattern display that allows you to highlight any azimuth or elevation "slice" and directly read the gain at any angle with a fully positionable cursor, or immediately switch to a 2D display for more detail.
EZNEC is specifically designed to be friendly and easy to use while taking full advantage of the powerful and versatile NEC-2 calculating engine. EZNEC is completely menu-driven; all entries and changes are done directly and quickly. Wire, source, load, transmission line, and ground entries are done in a spreadsheet-like format. Many shortcuts are built in. For example, wires can be rotated with a simple command to design vee and delta loop antennas without having to polish your trigonometry skills.
Antenna height and wire length likewise are easily changed. Groups of wires can easily be stacked, moved, copied, or rotated. Helices and loops are created with a few keystrokes, and loop size is easily and quickly changed. EZNEC lets you directly enter series or parallel RLC values for loads or L network components. Want to analyze phased arrays? EZNEC provides transmission line (with or without loss), L networks for feed systems, and true current source models. With 500 segment capability, EZNEC can model very long and complex antennas.
This application can model wire and insulation loss and calculates loss data for traps or loading coils.System requirements800 X 640 (SVGA) or better graphics
Limitations in the unregistered versionThe maximum number of segments allowed in any model is 20
You can't update the demo version with standard EZNEC maintenance updates