(Mini Numerical Electromagnetics Code) Version 3. M MANA is an antenna analyzing tool based on the moment method introduced in MININEC Software beta testing was provided by a group of fellow amateurs. Nobuyuki Oba JA7UDE wrote an English user manual in 2001. Gontcharenko Gary DL2KQ-EU1TT developed and released English versions of MMANA in 2001-2002. If you are a MAC user and have the need to do some antenna modeling, give cocoaNEC a try, I think that you will like it.MMANA-GAL Antenna Modeling Program Author: Makoto (Mako) Mori JE3HHT © 1999-2000 Currents in the various conductors making up the antenna elements can also be plotted, as well as a complete tabulation of the NEC engine output. Other outputs consist of a 3-dimensional radiation pattern, driving point impedance and VSWR, as well as a physical plot of the antenna’s geometrical structure. The antenna can be modeled in free space or above a conducting ground, and the ground conductivity can be varied. The different color lines represent different frequencies. The summary output for a three-element Yagi antenna located 10-meters above the ground is shown below. The antenna’s input information consists of its geometry (for a conductor, the x, y, z coordinates of its endpoints), its excitation, and type of ground (if any). The spreadsheet approach is simpler, however, the NC programing interface is more powerful. The antenna characteristics can be input in either one of two ways, via a tabular spreadsheet interface or a special NC programing language interface. “cocoaNEC” uses the NEC-2 computational engine. NEC (Numerical Electromagnics Code) was developed by Lawrence Livermore Laboratories in 1981 to simulate the electromagnetic response of antennas and other metal structures. Example antenna files can also be downloaded from Kok’s webpage. The downloaded program includes a reference manual and tutorial. This program takes advantage of all the cores of a modern Intel processor, therefore, it runs fast. The best part, however, is that the program is free. The program will run on OS X 10.6 or later, I have been running mine on the latest MAC operating system OS X 10.10, Yosemite, with no problems. This elegant and fast running program is written in OS X’s native programming language.

The program is “cocoaNEC” ( ) written by Kok Chen a retired Apple software engineer. I have now found an even better program than EZNEC, that is written specifically for the MAC.

I have always wished to have a similar program for the MAC. On my windows PC, I used EZNEC ( ) which costs about $100. I occasionally have need for an antenna modeling program. One disadvantage, however, is that not all types of programs are written for the MAC. I like using MAC computers because of the inherent stability of the underlying UNIX operating system, and the immunity to most viruses.

Antenna modeling program