( page updated 05-19-2001)

The unofficial Numerical Electromagnetic Code (NEC) Archives

To contact archive maintainer:   raymond.anderson@sun.com


 
File Name Short File Description
NEC  Executables, Source Code and Documentation
ANTENNA.EXE ANTENNA.EXE is a self unzipping DOS file containing WIRE, based on some 
of the original MiniNEC work.  However, the changes were so drastic that it can no 
longer referred to it as a variation on MiniNEC.  One feature that it has is that it can 
handle coaxial structures.  Thus a coax can be analyzed as two wires of different radii. 
There is care required at the terminations since there is fringing capacitance 
since an actual end-cap has not been included. A paper covering the theory behind
WIRE is also available for download.

The plotting of current and patterns were designed to be rather straight 
forward.  The package can handle up to about 160 unknowns in DOS.

program and documentation provided by author Dr. William A. Davis <wadavis@vt.edu>

mininec3.zip BASIC source code and DOS executable for mininec3 from NOSC  (Naval Ocean Systems Command)
mininec_help.txt Help file covering the use of the Mininec antenna modeling program. Of particular use to those not having access to a copy of the Mininec manual. (contributed by Jeff Jones AB6MB, jeffj@cbnewsm.cb.att.com) 
mininec_doc_sources.txt A short text file giving document #'s and order address for MININEC documents. 
nec2d_me.zip Version 1.02 
A Win32 executable targeted to the PentiumPro or later IA 32 machine and using allocatable arrays so that one program handles all structure geometry sizes. The folder also has a SOMNEC executable and the modified source code (Fortran 90).

contributed by Joe Lastovka  (joe_lastovka@yahoo.com)

nec2d_lapack.zip Version 1.02 
Same as NEC2D_Me except that it uses the Intel MKL LAPACK routines to factor and solve the NEC matrix equations. Pentium III only. About 20 times faster on matrix factor and solve at large matrix sizes.

contributed by Joe Lastovka  (joe_lastovka@yahoo.com)


vis_nec.zip
Version 1.03
Visual NEC 
A first cut at a Windows GUI to NEC2D. Also incorporates the Intel LAPACK routines, and so is Pentium III only. Also integrates SOMNEC into the GUI.

contributed by Joe Lastovka  (joe_lastovka@yahoo.com)

nec_viewer.zip Version 1.02
A first cut at a Windows program for plotting the segments defined in an NEC input deck and visualizing the structure

contributed by Joe Lastovka  (joe_lastovka@yahoo.com)

NEC2_Mac_.hqx NEC2 executable for the Macintosh (68K) with math coprocessor. 

from Barry Newberger (bsn@fusion.ph.utexas.edu)

NEC2_Mac_README.txt Document file for Mac version of NEC2 
NEC2_Mac.sea.hqx NEC2 executable for PowerPC Macintosh. Also a version for 68K Macs with no coprocessor. Fortran source code is included. 

from Barry Newberger (bsn@fusion.ph.utexas.edu)

NEC2_Mac_PPC_.txt Document file for PowerPC (PPC) version of Macintosh NEC2
nec2.macosx-darwin.ppc.tar.gz NEC2 compiled for Mac OS X / Darwin 1.2.1.

This binary was produced on a Power Macintosh G4/400 running OS X Public Beta

This binary was compiled from the NEC2 C source. The C source was obtained from
Raymond Anderson's Unofficial Numerical Electromagnetic Code (NEC) Achive.
(http://www.qsl.net/wb6tpu/swindex.html). The source was originally from the
ucsd.edu archives, and was converted from FORTRAN to C using f2c, according to
the Unofficial Archives.

Some modifications to the original Makefile and sources were necessary for the
sources to compile. I could not get the sources to compile using the supplied
f2c.h headers, so the f2c library from Bell Labs (netlib.bell-labs.com) was
installed and linked to produce the final binary. Typographical errors in the
Makefile and some sources which prevented compilation and linking were also
corrected.

The gzipped tar file contains the executable, a README file, diffs to document source  changes and several example input files.

contributed by Derwood Eadie (KG4EFO@arrl.net) 21 Nov. 2000

nec-pc.zip NEC2D executable compiled to run on PC 386/486 Compiled with 32-bit Lahey Fortran. Requires 80x87 math coprocessor. File contains 4 versions compiled for different maximum numbers of segments and hence require differents amounts of memory Includes SOMNEC2D.EXE Sommerfeld parameter generator. 
    Name of    Max number  Approximate  
    executable of segm.    memory use (MB) 
    - - - - - - - - - - - - - - - - - - - - - - 
    NEC2D.EXE       256        1.5 (*)
    NEC2D512.EXE    512        5 
    NEC2D960.EXE    960       16 
    NEC2D1k4.EXE   1392       32 
(*) NEC2D.EXE should be in the directory from where you run the other executables, it is the only one that contains the DOS-extender. The others borrow it from NEC2D.EXE.
    (updated 1/22/96) from Jozef Bergervoet (bergervo@prl.philips.nl)
nec-pc-x.zip This zip-file is a supplement to nec-pc.zip. It contains larger versions of the NEC executable, for problems with more than 1392 segments. They can only be used together with NEC2D.EXE, from nec-pc.zip. 

Description of the NEC2D files: --------------------------------------------------------------------------

EXAMPLE.DAT is an input file with several examples. These can be tested in one single run by giving this file as input.

NEC2D***.EXE Several working version of the NEC program. Differences:
         
        Name of      Max number   Approximate
        executable   of segm.     memory use (MB)
    - - - - - - - - - - - - - - - - - - - - - -
             /    NEC2D.EXE        256         1.5 (*)
 These are  |     NEC2D512.EXE     512         5 
 found in   |     NEC2D960.EXE     960        16 
 nec-pc.zip |     NEC2D1K4.EXE    1392        32 
             \    NEC2D1K9.EXE    1950        60 
             /    NEC2D2K8.EXE    2800       122 
These files |     NEC2D4K.EXE     4000       247 
  are in    |     NEC2D5K7.EXE    5700       500 
nec-pc-x.zip|     NEC2D8K1.EXE    8100      1006
             \    NEC2D11K.EXE   11000      1852

(*) NEC2D.EXE should be in the directory from where you run the other executables, it is the only one that contains the DOS-extender. The others borrow it from NEC2D.EXE. 
F77L3.EER Contains the text for Fortran error messages (nec-pc.zip.)

*.FOR, *.INC Files containing the Fortran source code. In nec-pc-x.zip --------------------------------------------------------------------------

Jos Bergervoet, bergervo@natlab.research.philips.nl bergervo@iaehv.nl

nec2pc.zip NEC2 executable for DOS. Runs on 286 or better processor. Requires math coprocessor. from Malcolm Packer (from Malcolm_Packer@cpqm.saic.com)
nec2.sun4.dl.Z SUN4 executable (dynamically linked) of NEC2 compiled for 1000 segments (Modified for interactive input/output filename specification) from Weston Beal (weston_beal@mentorg.com)
nc2s1500.sun4.Z SUN4 executable (statically linked) of NEC2 compiled for 1500 segments from John Boyer (john.boyer@rd.eng.bbc.co.uk)
nec2sx.tar

nec2sx

3/22/01

Fortran 77 source code of single-precision NEC2 modified with  FACTR and SOLVE routines modified to support non-transposed matrices for faster runtime performance. File nec2sx.tar contains the Fortran source code and simple compilation directions.

File nec2sx is a compiled SUN Solaris executable that also includes support for multithreaded execution. See the documentation in the source code tar file for setting up the multithreaded environment variable. This executable is compiled to support 1500 segments. Compiled on Solaris 2.5.1, also tested on Solaris 7 and 8
 
 

contributed by Ray Anderson WB6TPU  <raymond.anderson@sun.com>

nec2dx.tar

nec2dx

3/22/01

Fortran 77 source code of  double-precision NEC2 modified with  FACTR and SOLVE routines modified to support non-transposed matrices for faster runtime performance. File nec2dx.tar contains the Fortran source code and simple compilation directions.

File nec2dx is a compiled SUN Solaris executable that also includes support for multithreaded execution. See the documentation in the source code tar file for setting up the multithreaded environment variable. This executable is compiled to support 1500 segments. Compiled on Solaris 2.5.1, also tested on Solaris 7 and 8

contributed by Ray Anderson WB6TPU  <raymond.anderson@sun.com>

nec2.rs6000.Z IBM RS/6000 executable of NEC2. Runs under AIX 3.2 from Doug Braun (dbraun@iil.intel.com) 
nec2.rs6000_readme.txt Document file for RS/6000 version of NEC2 
nec81.tar.Z

nec81.zip

Fortran 77 source code for nec-81. (modified for 3000 segments) (Previously listed as nec3, but renamed to alleviate confusion with the real nec3.) (from Petri Kotilainen OH3MCK) 
nec81.readme.txt Readme file for nec-81 modeling program.
nec2_src.tar.Z Fortran source code for NEC2 
nec2.in.c.tar.Z NEC2 source code in C. Converted from Fortran with f2c. (from ucsd.edu archive) 
nec2.linux.Z NEC2 executable for Linux. Compiled with g77 from Jim Cronin N2VN (jdc@cci.com)
nec2.linux_src.tar.Z NEC2 source code in Fortran hacked to compile with 'g77' Contains nec2a.f and secnds.f (a dummy version of secnds) Builds with the following command line under Linux: g77 -o nec nec2a.f secnds.f from Jim Cronin N2VN (jdc@cci.com)
nec2.hpux.Z NEC2 executable for HP 700 series workstation running HPUX version 9.02 from Charlie Panek (charlier@lsid.hp.com) 
nec2.hpux.f.Z NEC2 Fortran source code for HPUX version. This code was modified from nec2_src.tar.Z found in this archive to be compatible with HPUX version 9.02 from Charlie Panek (charlier@lsid.hp.com) 
nec2.hpux.txt Short text file describing the changes made to original FORTRAN source code to make it run under HPUX. 
SOMNEC2D.EXE is used to generate SOMMERFELD parameters in advance. It is only needed for jobs that use it, e.g. some of the examples in EXAMPLE.DAT. Before running those jobs, SOMNEC2D should be called (see NEC documentation.) Input for example jobs: 4 .001 10 1 It makes the files: SOM2D.OUT (ascii) and SOM2D.NEC (binary) that are later used by NEC2D. In that case NEC2D creates a further file NGF2D.NEC (binary.) SOMNEC2D.EXE is found in nec-pc.zip.
INSTYGO2.EXE IYAGI GENETIC OPTIMIZER II ------------------------- 

YGO2 is a FREEWARE progarm. It may be freely copied and distributed, but ONLY as long as there is no cost to the recipient.

Unlike the original release of YGO, this version allows the user to optimize the array at up to 15 different frequencies, and to specify a different driven element (if desired) at each frequency. Unexcited DEs are assumed to be terminated in the feed system characteristic imped- ance.

YGO2 (YAGI GENETIC OPTIMIZER II) designs optimized Yagi antennas using one of the most recent and powerful techniques in applied electro- magnetics: a genetic algorithm. A genetic algorithm mimics natural sel- ection ("survival of the fittest") by creating generations of Yagi designs in which the best designs ("individuals") pass their design parameters ("genes") onto the next generation in such a way that better and better antennas are the result. GA optimizers can produce remarkable results not achievable with any other design technique. Genetic algorithms are superior to deterministic optimzers, and they are easily implemented on a PC.

YGO2 is user-friendly and easy to run. All GA parameters are changed by editing a single set-up file. The user can specify popu- lation size, number of generations, antenna figure-of-merit, and all other parameters needed by the GA. The Yagi's performance is computed using NEC-2D, the state-of-the-art Numerical Electromagnetics Code (double precision) developed at Lawrence Livermore National Laboratory.

When YGO2 has completed its optimization, the radiation pattern of the best antenna is plotted on screen. A separate plotting utility allows the user to view radiation patterns for other top designs on a generation- by-generation basis. One of the GA's most attractive features is that, instead of producing only one "best" design, it produces groups of designs that achieve similar performance. The designer can then select from these groups the Yagi that best meets the requirements.

To install YGO2, copy the file INSTYGO2.EXE into the directory on your hard drive that you will use for YGO2. YGO2 files are created by executing  INSTYGO2.EXE, which is a self-extracting EXE file. If you have a previous version of YGO2, simply overwrite all files of the same name.

Be sure to check the README.TXT and YAGI_GA.TXT files for inform- ation on setting up a YGO2 run. The file NEC2INFO.TXT contains information on creating various size NEC-2D executables. Any changes to YGO2 will be described in the file UPDATE.TXT. Please read UPDATE.TXT if it is present.

YGO2 is a DOS program that must be run under MS or PC DOS (ver.3.3 or higher), Compaq DOS (ver.3.31 or higher), or in a DOS window under MS Windows 3.0 or higher. YGO2 also requires an 80386/87 math coprocessor or higher CPU and about 1 MB of RAM (depending on the model size).

Contributed by Phadean Engineering <phadean@ieee.org> PO Box 611, Shrewsbury, MA 01545-8611 USA, tel. (508) >869-6077, fax (508) 869-2185)

ygo3inst.exe  Latest Version uploaded 4/19/2001

 YGO3 (Yagi Genetic Optimizer, Ver. 3) is a real-valued genetic
algorithm (GA) that designs optimized Yagi-Uda arrays by maximizing a
user-specified figure-of-merit (FoM).  Antenna designs created by YGO3 
are modeled by NEC-2D (Numerical Electromagnetics Code, Ver. 2, double
precision), a recognized standard for modeling wire antennas developed
at Lawrence Livermore National Laboratory.  YGO3 handles up to 150 ele-
ment arrays at up to 50 frequencies.  The GA includes state-of-the-art
techniques such as quadratic interpolation, auto-grooming, coefficient
perturbation, coefficient activation, several selection methods, and two 
crossover methods.  YGO3 is a DOS program which may be run in a DOS win-
dow under the Windows operating system.

 YGO3 is a FREEWARE program.  It may be copied and distributed
without restriction as long as there is no cost or charge of any kind,
including "tie-in" costs, to the recipient.  YGO3 has been developed and
is distributed as a service to the amateur radio community.  Please email
comments, suggestions, or questions to: ygo3@yahoo.com.

 YGO3 is installed by executing the self-extracting file
YGO3INST.EXE in the default directory, usually C:\YGO3.  All necessary
files are created, including several versions of NEC-2D that allow for
models with 28 to 1500 segments.  Please read the file YGO3_MAN.TXT for
setup and operating instructions.

 YGO3 is the successor program to YGO2, a binary-coded genetic
algorithm for optimizing Yagi arrays.  Because YGO3 includes several
improvements, designers using YGO2 should upgrade to the newer real-valued
GA.

Contributed by Phadean Engineering <phadean@ieee.org> PO Box 611, Shrewsbury, MA 01545-8611 USA, tel. (508) >869-6077, fax (508) 869-2185

NEC Utilities and Related files:
 4nec2v23.exe New version 2.3 (2/27/01)

A Windows utility that facilitates the generation of NEC source decks and viewing of the resultant output.

Contributed by the author [Arie, P.O. Box 73  7160-AB Neede, The Netherlands]

eam_demo.zip  eam_demo.zip EAM (electromagnetic antenna modeling) demo by SAIC (Science Applications International Corp.) Runs under Windows 3.1 (DOS). EAM is a graphical user interface to NEC and BSC. Demo version has limited capability but allows visualization and inspection of small to medium size input deck and output files. (from Malcolm_Packer@cpqm.saic.com) 
gamtoz.zip GAMTOZ is a program to convert MicroSmith .GAM files (such as produced by ELNEC and EZNEC as well as by MicroSmith) to comma- delimited files containing impedance values. Both source code (GAMTOZ.BAS) and a compiled (DOS) version (GAMTOZ.EXE) are included. (This copy virus free!) 

from Roy Lewallen W7EL 

jgraps.zip Reads NEC output files and plots radiation patterns. Written in Visual Basic and runs under Windows 3.1 in a PC DOS environment. (Revision 1.5 of 5/12/94) written by John Boyer (john.boyer@rd.eng.bbc.co.uk)
lpcad23.zip LPCAD23 is a program to design log-periodic antennas. Antenna specifications are input and the program calculates the physical lengths and spacings. A NEC or NEC for Wires input file is then automatically created.. (New version Rev 2.0 replaces version 1.37 with bug fixes and enhancements as of 1/29/96) (Version 2.3 replaces version 2.0 as of 4/10/97 (contributed by the author Roger Cox WB0DGF) <hygain@compuserve.com>
lpcad27.zip LPCAD27 is a program to design log-periodic antennas. Antenna specifications are input and the program calculates the physical lengths and spacings. A NEC or NEC for Wires input file is then automatically created.. This is version 2.7 

(contributed by the author Roger Cox WB0DGF) <Roger.Cox@telex.com>

mynec4pc.zip | | | NEC POST-PROCESSOR V. 2.1 | |

necpost2.bas is Nec-post-processor 2.1 developed by Agostino Rolando . The original file was necpostproc.bas by J. Boyer. 

I have taken Necpostproc.bas and nov.bas and mixed them together to display 2d - 3d radiation patterns and current distribution along the antenna .

It works better with vertical radiators.

This 2.1 version has eliminated some little bugs of earlier 2.0 .

Note that ,in order to draw a true 3d radiation pattern, the antenna must be arranged as to have the feed point just in (0,0,0) coordinates.

For yagi design, I found a good agreement with yagimax 3.0 program by Lew Gordon.

Here you find : 

nec2pc.exe - nec2 for pc. Requires 486dx or better and as much memory as the number of segments you use for antenna's description.

niv.exe - nec input viewer. Shows input structure descriptor files *.nec. You can evidentiate errors in designing your antenna before nec2pc processing.

nov.exe - nec output viewer . Shows the distribution of currents along the antenna (*.out files).

necpost2.exe - nec postprocessor . Shows radiation patterns and current distrib. for *.out files.

A few sources examples are included.

NOTE : To know how to compile input descriptor files, see Nec User's Guide in http://www.traveller.com/~richesop/nec/ , available in pdf format.

Have a good work !

Agostino Rolando E-mail: rolago@iname.com

nec_docs_order_info.txt Provides info on ordering official NEC2 documentation from the government. (updated 12/29/98)
nec_exe.zip NEC.EXE an interface to SOMNEC data 

This utility (nec.exe) runs from the command shell (DOS prompt) and opens a NEC input file and determines if the Sommerfeld ground is used and obtains the frequency, K and sigma terms so it can locate or generate the appropriate SOMNEC interpolation grid before invoking one of the variants of NEC2D. This SOMNEC data is stored for future use; the user can specify the location of this data by setting the SOMNEC environment variable. 

NEC.EXE also determines the appropriate variant of NEC2D based on the number of in-core segments. The program requires nec2d512.exe, nec2d960.exe, nec2d1k4.exe, and RTM.EXE in the current directory or the PATH environment variable.

Source code included (The program could also be recompiled on Unix afer some modifications.) 

*** NOTE: If you downloaded this prior to 12/29/98 and are experiencing problems, download the new version now online which has been modified to include some missing library files.

(contibuted by the author Ralph Holland , VK1BRH <vk1brh@dynamite.com.au> <http://www2.dynamite.com.au/vk1brh>)

nec_hist.txt Article from the ACES newsletter outlining the history of the various versions of NEC
nec_param_util.Z Perl script to create NEC input files from parameterized physical descriptions. from Doug Braun (dbraun@iil.intel.com)
nec_post_processor.Z Creates polar plots from NEC output. MS Quick Basic source code. from John Boyer (john.boyer@rd.eng.bbc.co.uk)
nec2pp_1.2.tar Announcing the release 1.2 of npp. Npp is a nec2 executable and graphic post processor for Linux. It is based on a version of NEC2 slightly modified and on the graphic package "yorick". NEC2 source code, executable, yorick npp script, somnec, and numerous example antenna files included. 

It allows:

* To run nec2 passing the name of the file .nec 

* To visualize in X-windows radiation diagrams of antennas, 

* To display the main results as Gain, F/B, Z etc. 

* To produce Post Script files to be printed

Requirements:

Npp reqires yorick 1.4. (available from ftp://ftp-icf.llnl.gov/pub/Yorick/)

If you wish recompile nec2 you need yaf77-1.3

(provided by Pino Zollo I2KFX <pinoz@highway.com.py>)

nec2prt1.pdf NEC2 manual Part 1 (Theory of Operation). This file must be viewed with Adobe Acrobat or other compatible viewer. Original was scanned, cleaned up and ultimately converted to .pdf format. 

(contributed by Alexandre Kampouris)

nec2prt2.pdf NEC2 manual Part 2 (Program Description - Code).  This file must be viewed with Adobe Acrobat or other compatible viewer. Original was scanned, cleaned up and ultimately converted to .pdf format.

(contributed by Alexandre Kampouris)

nec2prt3.pdf NEC2 manual Part 3 (User Manual)  This file must be viewed with Adobe Acrobat or other compatible viewer. Original was scanned, cleaned up and ultimately converted to .pdf format. 

(from Unofficial NEC Home page  ttp://members.home.net/nec2/)

necdraw.zip DOS utility for verifying correctness of NEC models. Checks adherance to rules and provides 3-D display of model. (from ACES archive) 
nec_examples.txt This collection of NEC2 input data files is provided courtesy of the Internet and Raymond Anderson. These input files may be used for the NEC-PC programs, I've tried them on both, but have been using NEC2D primarily. NEC2D was provided by Jozef Bergervoet. I tried to give enough examples so that the control cards for input would be self explanatory. Also most types of antennas have been included such as log periodic, monopole, rhombic, deltaloop, Quad and the YAGI. These files are easily adapted and modified with the DOS edit function, using the search and replace features. 

Good Luck on your antenna designs- Clyde Edgar WA6DCM 

from Clyde Edgar WA6DCM <Edgar@courier1.aero.org> 

nov.zip NEC output current viewer. Written in QuickBasic 4.5 source code included. Allows visualization of geometry and the current in each segment. Has rotation and zoom capability. (contributed by David de Schweinitz (dave.des@metronet.com)
nv.zip NEC geometry viewer. Written in QuickBasic 4.5 . Includes source code. Allows visualization of a structure described in a NEC input file. Has rotate about all three axis and zoom capability. (contributed by David de Schweinitz (dave.des@metronet) 
nvnew.zip NVNEW.ZIP contains an enhanced version of David de Schweinitz's NV
program.  These enhancements are in NVNEW.BAS/NVNEW.EXE and include
support for GA, GH, and GM cards as well as support for VGA graphics.
I also added the capability to print out (in monochrome) the displayed
NEC structure.  Several different types of printers are supported.  See
PRINT.NV for more information on how to use this feature.

Glenn Stumpff
gstumpff@yahoo.com

Pointer to on-line docs On-line NEC2 manual at URL http://members.home.net/nec2

(unofficial NEC home Page) also maintains links to other NEC resources

somnec_readme.txt This is the text file contained in somnec.tar that provides a general discussion of the program. 

contributed by George Christianson <gchristianson@pppl.gov> 

somnec.tar.Z This file contains the FORTRAN source code for the SOMNEC utility described in the official NEC2 documentation, as well as a sample output file and a brief text file containing a general discussion of the program.The SOMNEC program generates grids used by the NEC2 program for the Sommerfeld-Norton approximation to realistic grounds. 

contributed by George Christianson <gchristianson@pppl.gov> 

Win-ni.zip Win-ni, Windows to Nec Wires(tm) interface.  Provides a
windows driver for the Nec Wires suite from K6STI.  The
window application allows Edit, Run, Plot, View, Sweep, and
Convergence parms from one screen. You must possess a licensed
copy of K6STI's 'Nec Wires' to utilize this add-on.

contributed by the author  Patrick Wintheiser  W0OPW  <w0opw@yahoo.com>

wiregrid.zip WIREGRID is a NEC2 pre-processor for DOS PC's that was developed for modelling metallic structures using a mesh of wires. It has powerful automatic facilities for controlling the density of the mesh once the structure has been broken down into a number of polygons. It can also be used as a general NEC2 pre-processor. It was originally written by C.F. du Toit. Note that the code uses its own data format, and unfortunately CANNOT import an existing NEC2 model file, but it can of course export the model to a standard ASCII file. A description of the pre-processor has been accepted for publication: "WIREGRID: A NEC2 preprocessor", C.F.du Toit & D.B.Davidson, Applied Computational Electromagnetic Society (ACES) Journal. (To appear.) A draft version of the paper (minus illustrations) is contained in the ZIPfile. The code was compressed using PZKIP version 2.04g. (wiregrid.zip Version 4.00 A now online 9/8/94) 

from Dr. D.B. Davidson (davidson@firga.sun.ac.za ) 


wg_211.zip 
WireGrid for Windows is a NEC pre-processor for modelling metallic structures using a mesh of wires. WireGrid AUTOMATES the DISCRETISATION of conducting surfaces (polygons) in terms of wire meshes for analysis in NEC, and allows VISUAL FEEDBACK of the model structure as well as the positions of sources, networks and field points. It also does CHECKING regarding duplicate wires and closely spaced nodes not making contact. 

WireGrid for Windows (version 2.11) is the second release of this NEC pre-processor. WireGrid was developed by EM Software & Systems in collaboration with the University of Stellenbosch.

(Note: the version on the this ftp site is enabled in the DEMO mode. It is fully functional but limited to 15 elements.)

from Dr. F.J.C. Meyer (fjcmeyer@emss.co.za )

W5GFE.tar.gz "Jiffy" - by Bill Walker W5GFE (bw@cs.ecok.edu) 

This is a suite of programs written in BLT - an extension of TCL/TK - which are intended to assist in visualizing antennas. The package is intended to provide windows which show both antenna patterns and antenna configuration. An accompanying article in both LaTeX and PostScript form describes the process of designing a simple antenna using the system.

The suite has been built under SCO 5.0.2 and SCO 5.0.4 (Free SCO), but should run under any system that can make the blt extension of tcl/tk work. (That should be the majority of systems on the planet.)

(contributed by Bill Walker W5GFE , <bw@cs.ecok.edu >

W5GFE2.tar.gz W5GFE Antenna Toolkit  - a Perl Toolkit for analysis of NEC2 files

 SYNOPSIS

  Necview
  Azimuth  [filename]
  Elevation [filename]
  Wires

 DESCRIPTION

These programs are written in Perl/Tk (version 5.005_2),
and provide tools which can help to visualize antennas or analyze data 
which is produced by NEC2 - the antenna modeling program.

The NEC2 program is commonly used by radio amateurs or professional
antenna designers on Unix equipment to model antennas.  While NEC2 is quite 
versatile, the output of NEC2 is voluminous and difficult to read.  This suite of programs
provides graphical depictions of NEC2 output.

Azimuth provides three graphs of "horizontal"
radiation patterns:  an ARRL-scaled polar
plot, a linearly scaled polar plot, and a cartesian plot.  A "fact box"
provides indication of -3 DB beam widths.

Elevation provides similar information for vertical radiation
patterns.

Wires is a visualization tool which shows three views of the same
antenna.  Views are provided for the "XY plane", the "YZ plane" and
the "XZ plane".

Necview borrows heavily from the "xnecview" program by
P.T. de Boer (pa3fwm@amsat.org). 
 
 

Sample data files are included in each subdirectory.

The W5GFE Antenna Toolkit is released
under terms of the GNU Public License.
 
 

 AUTHOR

Bill Walker, W5GFE, bw@cs.ecok.edu

XLNEC.zip Latest rev uploaded 5/7/2001

NEC.XLS 

Updated version VB1.10 (1/12/99) now online.

NEC.XLS contains pages to handle the following topics: 

 1 INTRO 
 2 DECKMAKER 
 3 VIEWER 
 4 AUTO NEC 
 5 DISPLAY 
 6 ANALYSER 
 7 DIPOLE 4 STACK 
 8 DIPOLE 4 STACK(2) 
 9 FOLDED STACK 
 10 ROTATABLE FLATSTACK 
 11 TILTED DIPOLE 
 12 HELIX and MICRO LOOP 
 13 TAPERED HELIX and MICRO RING 
 14 ANTIPHASED HELIXES 
 15 LPDA 
 16 LPV  1 
 17 LPV  2 
 18 DISCONE 
 19 BIFILAR 
 20 SLOTTED RING 
 21 FOLDED DIPOLE 
 22 FRANKLIN 
 23 VERTICAL FRANKLIN 
 24 LAZY - H 
 25 PARABOLIC YAGI 
 26 DIPOLE withPARABOLIC REFL. 
 27 YAGI MAKER 1 
 28 YAGI MAKER 2 
 29 LAUNCHER 
 30 CORNER REFLECTOR 
 31 STANDARD GAIN 
 32 DECK FILE INDEX 
  REVISION HISTORY 
 

AN ANTENNA MODELLING PROGRAM, INTEGRATING THE CONVENIENCE of EXCEL with the POWER of NEC 2 ...for experienced EXCEL users, with access to adequate computing power.

Release 1.07A ,1/7/98. This version, released privately, has a restricted number of prepared antenna design sheets. The Workbook is not locked, with the intention that users may add their own antenna design sheets. No charge is made, nor any responsibility accepted .

WHAT NEC.XLS DOES The series of sheets in NEC.XLS allow you to automate most of the common tasks associated with using a NEC 2 engine for modelling antennas, and tabulating the results. This program automates your entire antenna assessment. It will step through up to three design variables at a time , with increments as selected. Having incremented chosen variables, a NEC INPUT DECK is automatically built. This is fed to a NEC 2 engine automatically. The Output file from the NEC engine is then read by EXCEL, and a summary of gain, F/B, and antenna input impedance is produced. If desired, a Thumbnail plot for each design is produced. Finally, a table of results is available, which is sorted by a Figure of Merit based on your weightings. The program thus loops away, building and summarising design changes within your set parameters.

(contributed by the author Peter Ward <pward@net-tech.com.au> Bairnsdale, Victoria, Australia )

RF1.zip

RF2.zip

Uploaded 5/7/2001

RF1.xls, and RF2.xls (Release 4.12, 04/9/2001) 
 These workbooks form a practical companion to the automated NEC design package, which is available on this site as XLNEC.ZIP (and which is unchanged except for the readme file now included in Microsoft Word format)
Both RF1 and RF2 have much added material, and a Readme with expanded detail of content. In particular, a little more help re. correcting problems with Excel's losing track of its macros.
  Every page in these workbooks was put together to assist in solving a real day-to-day problem in a workshop dealing with antenna design and construction. They contain practical modules for solving every formula-related RF problem the author has encountered.
In particular, there are sheets that will help de-mystify these topics, and more!
    ANTENNA GAIN CALCULATIONS
    PATH BUDGETS
    STUB CALCULATION and PLACEMENT
    PHASE TILT
    VSWR CALCS
    BUILD MMIC IN-LINE AMPS .. that replicate the gain curves in the HP app notes.
    BUILD BROADBAND DIRECTIONAL COUPLERS good to 1 gHz, for $20
    IMPEDANCE MATCHING
    POWER DIVIDERS
    SLOTTED LINES
    PATTERN TILT on COLINEARS
    SLUG TRANSFORMERS/MATCHERS
    IMPEDANCE CHARTING
    MATCHING with IMPEDANCE CHARTS
    CABLE LOSS CALCULATION for ANY CABLE
    RETURN LOSS UNCERTAINTY
    INDUCTOR and OP-AMP CALCS
    RSSI CALIBRATION CURVES as a basis for ACCURATE RF MEASUREMENTS
... and a couple of ring-ins. CYLINDER HEAD FLOWBENCH may interest some
 The books contain macros. To relieve the fainthearted, they are verified against the latest PC-Cillin Signatures, and directly uploaded ONLY to the 'Unofficial NEC Archives' for your protection. The macro pages are unlocked, and I encourage modification and suggestion for improvement.
 Please pay attention to README.RTF, which gives instruction for the correct setting up of Excel, and has been a matter of some frustration to many!
 The material is offered freely to the users of 'The Unofficial Nec Archives' as an encouragement to those of you whose RF experience goes beyond just buying the 'latest and greatest'. It is my contribution to helping 'keep the dream alive'! 
  From the workshop of 
                    Peter Ward, AX2VCI.  Bairnsdale, Victoria, Australia
                    pward@net-tech.com.au
 

xnecview-1.0.tar.gz X N E C V I E W  Version 1.0- A program for previewing NEC2 structure files (Unix/X-windows). Allows zoom in, zoom out, rotation and panning. Should compile on most Unix systems. Includes C source code, Makefile and Imakefile and brief README docs. Distributed under GNU GPL. 

(contributed by the author Pieter-Tjerk de Boer PA3FWM pa3fwm@amsat.org or ptdeboer@cs.utwente.nl)

ANTENNA  MODELS:
EZNEC_FILES Directory containing contributed EZNEC antenna description files.