( page updated  June 6, 2005)

The unofficial Numerical Electromagnetic Code (NEC) Archives

To contact archive maintainer:   raymonda@ieee.org


  Quick Links to the most popular downloads: 4nec2      nec2++     nec2c     MultiNEC
 
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 Minninec3
BASIC source code and DOS executable for mininec3 from NOSC  (Naval Ocean Systems Command)
mininec_help.txt Minninec3 help
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 Minninec3 doc sources
A short text file giving document #'s and order address for MININEC documents. 
NEC-2_for_MMANA_v_18.zip Updated  10/23/2003 to version 1.8

NEC2 for MMANA (Version 1.8)
The utility "NEC-2 for MMANA" is intended for calculation of antenna models made and optimized in program MMANA and for construction and simulation of antenna models using input language NEC-2 and based on MMANA models. Calculation is made with use of NEC-2, including calculations above a surface of the ground in Sommerfeld-Norton model and calculations with use NEC-2 Extended thin wire kernel. Also in "NEC-2 for MMANA" it is possible to make calculation in a case when some wires in MMANA model are in dielectric isolation. Correction and editing of NEC-2 input code is allowed using most of cards from input NEC-2 language. A maximum quantity of processable segments - 3000, NEC-2 engine compiled by Arie from Neede, Netherlands. All files of the program are placed in one directory, program must be used only as 32-bit windows application (Win 98/2000/ME/XP)

Further info is available at: http://www.qsl.net/ua3avr/

contributed by Dimitry Fedorov, UA3AVR (http://www.qsl.net/ua3avr)









Source code: Updated 1/25/2005
nec2pp_latest.tar.bz2


autoconf source distribution: Updated 1/25/2005
necpp-1.1.1.tar.gz


Windows executable (compiled under Visual C++): Updated 1/25/2005
nec2++.zip





Linux executable (Release 1.04 compiled under Suse Linux 9.0 by R. Anderson)
Updated 12/5/04
nec2++_linux.zip

nec2++

Latest release uploaded 1/25/2005

Release 1.1.1 2005-1-21

  • Cleaned up and reworked patch subdivision.
  • Fixed a bug in interpolate() caused by not having the precalculated data static. Thanks to Neokolis for pointing this out.
  • Cleaned up rom2() and rechecked program flow.

* Got LAPACK going. There is generally a 100% speedup. However the LAPACK 
routines sometimes
produce different answers to the built in LU decomposition routine? Therefore
LAPACK LU decompositions is still not included in the default build.
* Fixed up a re-initialization problem in the temporary geometry files.
* Several Improved testharness code.
* Moved temporary geometry into the geometry class. Set this up in the
geometry_complete() method.
* Added #include <unistd.h> to misc.cpp
* Ignore Radiation Pattern Polarization angles in the testharness where the
power level is -999 dB. These have no physical meaning and are often
different with LAPACK.


Release 1.0.7 2004-12-16

    * Switched command-line option parsing to XGetopt for cross platform compatibility
    * Fixed major bug in Win32 executable that caused a crash on file output (Thanks to Jerome Plet)
    * Added Visual Studio Project files
    * Changed member 'near' of nec_context to m_near to avoid a conflict with the VC++ reserved word 'near'
    * Modified the error message macro to allow compilation on Visual C++. This causes error messages to NOT have a content if nec2++ is compiled with a non-C99 standard compiler.

To build libnecpp, and use NEC from a C API, you need to use autoconf and friends -- to install these on Debian linux, simply type
apt-get install automake libtool

To build the library, download the autoconf distribution [878 kB] and issue the following commands:
tar -zxf necpp-1.0.7.tar.gz
cd necpp-1.0.7
./configure
make
make install

Release 1.0.6 2004-12-13

    * Fix for non-initialization of voltage sources if no excitations were specified (Thanks to Jerome Plet)
    * Cleaned up code for bad loop in nec_context (Thanks to Neoklis Kyriazis for this)
    * Removed old Numerical Greens Functions code and variables -- these were not doing anything (ib11 e.t.c.)
    * All system exit (stop()) calls have been removed and replaced by exceptions (apart from those inside the main command line programme)

Release 1.0.5 2004-12-10

    * Most of the system exit code has now been replaced by C++ (nec_exception*) exceptions. This allows error messages to be caught without terminating execution of the calling programme.
    * Windows executable as compiled for athlon-xp only.
    * Fixed a problem with initialization between multiple simulations on the same deck. This caused the second simulation (an XP card or RP card for example) to sometimes yield wrong results.
    * Some memory cleanups.

Updated 12/5/04
Release 1.0.4 2004-11-29

    * Added a benchmark command line switch (-b). We use this for
      comparing machines that will be used in clusters.

    * I have moved over to using autoconf and libtool. The original
      makefile is still working and most users should use that version to build nec2++.

    * NEC is now available from a C API, and linked as a library. See
      the example directory. To build the library, you need to use
      autoconf and friends (see above).

    * Speed up CMSET by eliminating multiple assignments.

    * Speed up using the safe_array::sum() method.

Updated 10/22/04
Fix up a bug in the Sommerfeld/Norton ground code (Thanks to Arie Voors for helping to locate this). This bug is probably present in nec2c as well, and will result in incorrect modelling.

Initial upload 9/24/04
NEC2++ is a port of the Numerical Electromagnetics Code (NEC-2) to C++. This work is based on the C port by N. Kyriazis, including pieces from additional work by Jeroen Vreeken. The new portions of code are licensed under the GPL.

Summary of Changes

  • Moved the geometry parsing to a separate file. Will move to PCCTS, and an API for specifying geometry.
  • Improved command-line syntax and handling of output file names.
  • Moved to a safe_array for all arrays.
  • Fixed many index-out-of bounds errors.
  • Created a testharness (nec2diff).
  • Introduced a typedef for nec_complex.
  • Modified output to be compatable with xnecview
  • Moved all graph output to separate class.
  • Moved Sommerfield Calclations to separate class.
  • Cleaned up complex calculations
  • Removed all compiler warnings [except one that indicates a piece of code I don't understand].
  • Renamed variables.
  • Moved a lot of #defines into local code.
  • Put in some code to allow the incident field amplitude to be specified when using an EX card (like NEC 4).

In the very near future, nec2++ will depend on the ATLAS. To install this use the following commands under DEBIAN linux (http://www.debian.org).

	apt-get install atlas3-base atlas3-headers atlas3-base-dev
apt-get install refblas3-dev lapack3-dev lapack3-doc
On other operating systems, you should look at http://math-atlas.sourceforge.net.To check for latest updates and other info see the authors web page:

http://www.physics.otago.ac.nz/research/electronics/nec/index.html


contributed by  the author Tim Molteno at the University of Otago, New Zeland ( tim_AT_ physics_._otago_._ac_._nz)
                                                       [remove _AT_ and other _ characters in e-mail address]







nec2c.tar.gz
(source code)







nec2c
(Linux executable)







nec2c_gccV2.96_patch.tgz
(patch to allow compilation with gcc 2.96)











nec2c.rxq-0.2.tar.gz
(Improved port by PE1RXQ)
Inital release 2/2/04
Bugfix uploaded 2/27/2004
Problem with data cards being listed in one line fixed. (missing \n in
a printf() statement inserted)

Description text updated 6/18/04

Patch available to allow compilation on gcc 2.96 compiler 6/28/04

Added link to PE1RXQ modified version 8/20/04
nec2c (nec 2 in C)

 
nec2c is a translation of the NEC2 FORTRAN source code to the C language.
  The translation was performed mostly "by hand" and a lot of modifications
  to the original program were introduced in order to modernize the NEC2
  and to remove as many built-in limitations as possible. The attendant
  SOMNEC program was also translated to C and incorporated in nec2c as a
  function so that Sommerfeld ground solutions are a part of the program.

  2. CHANGES:
  The following is a list of the more significant changes incorporated into
  nec2c during translation from FORTRAN to C:

  * All GO TO constructs have been removed (all 961 of them!) and "spaghetti"
  code sections untangled as far as was possible to the author. Still, a lot
  of the code is not as clean and straightforward as might have been.

 
* Obsolete memory-saving practices (such as "equivalences" of different
  variables) have been eliminated and memory-sharing variables have been
  separated so that they are independent.

 * All fixed-size arrays used in calculations have been replaced with
  buffer pointers which are allocated memory dynamically according to the
  needs of the program and the complexity of each structure's geometry.
  There is a two-fold advantage in this - there is virtually no limit to
  the complexity of a structure (number of segments/patches etc), and there
  is no wasted memory in fixed arrays. Additionally, there is no need for
  data storage/swapping between memory and files and therefore functions
  relating to this activity and also the NGF form of solution have been
  removed from the program.

  * When a Sommerfeld finite ground solution is requested, since the
  SOMNEC program has been incorporated in nec2c there is no need to store
  the ground grid data in a file and read it when running nec2c. Instead,
  ground grid data are calculated as needed and for each new frequency if
  frequency stepping is specified.

  * The factr() and solve() functions have been modified to handle the
  main matrix (cm) in untransposed form so that calculations are faster.

  * The parser that reads the input file allows the two characters of the
  mnemonic to be in lower case if preferred. It also allows comments to be
  inserted anywhere in the input file in Unix style, e.g. all lines
  beginning with a '#' are ignored.

  * Operationally, nec2c differs from NEC2 in not being an interactive
  application. Instead, nec2c is a non-interactive command-line application
  which accepts an input file name and optionally an output file name.
  If this is not specified, a name for the output file is made by stripping
  any extensions from the input file name and adding a ".out" extension.
  Furthermore, nec2c has the potential of being incorporated in another
  application (like a GUI) after suitable modifications, allowing the
  creation of a stand-alone program without the need for reading files
  produced separately.

  * My original motive for translating NEC2 into C was to make it easier
  to modify and modernize and to change obsolete functions and usage. As
  a result I have edited to some extend the format of the output file to
  make it more "human readable" (e.g. provided a single space between
  adjacent numbers to avoid a hard-to-read "chain" of numbers joined by
  - signs) etc. In my humble opinion these changes make the output file
  easier to read and possibly somewhat more presentable, although this is
  likely to be a problem with applications that read the output file in a
  rigid manner, based on the exact output format. I apologize for this
  change if it causes such problems but my intention is to eventually
  modify nec2c to be used as part of a graphical application, providing
  results for graphical plots directly in its buffers.

(the above extracted from the README file)


 The file nec2c.tar.gz contains the source code.

contributed by the author  Neoklis Kyriazis  5B4AZ   Limassol, Cyprus
(e-mail address in the README file)

----------------------------------------------------------------------------------

The file nec2c is a Linux executable compiled from the nec2c
source code with GNU gcc 3.3.1 running on a Suse 9.0 Linux system.
(compiled by Ray Anderson WB6TPU)

-----------------------------------------------------------------------------------
A patch is available that changes the definition of complex constants. It is
  needed to compile nec2c using compilers like 'gcc V2.96' or 'egcs-2.91.66' (and some others).

patch for gcc 2.96 contributed by Roland, DK1RM
(e-mail address in the README file)
--------------------------------------------------------------------------------------

The file nec2c.rxq-0.2.tar.gz  is an improved port based on the 5B4AZ port but with modifications by
Jeroen Vreeken PE1RXQ
( http://sharon.esrac.ele.tue.nl/users/pe1rxq/).
The code has been modified to present a cleaner structure and the output format is now compatible with xnecview and other post processors..
------------------------------------------------------------------------------------------------------




nec2d_me.zip nec2d_me

Version 1.02 

Notice: Several users have reported problems with nec2d_me and
nec2d_lapack. These problems were related to inaccurate results
when the NE card was in the input deck and software crashes when
an LD (load) card was present. The author's e-mail address appears
to be no longer active.

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
nec2d_lapack

Version 1.02

Notice: Several users have reported problems with nec2d_me and
nec2d_lapack. These problems were related to inaccurate results
when the NE card was in the input deck and software crashes when
an LD (load) card was present. The author's e-mail address appears
to be no longer active.

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)

nec2dx500.zip
nec2dx1500.zip
nec2dx3000.zip
nec2dx5000.zip

somnec2d.zip


nec2dx

Uploaded 4/22/2002

nec2dx is a double-precision code compiled with GNU g77. Runs as a 32-bit application in a DOS console window 
under Windows 95, 98, NT, 2000, and XP. 

These nec2dx executables have been generated from source code modified to allow 300 separate LD cards as opposed to the normal 30. Also modified with  FACTR and SOLVE routines modified to support non-transposed matrices for faster runtime performance 

Executables have been compiled for the following number of segments: 

                                          500  (nec2dx500.zip) 
                                        1500  (nec2dx1500.zip) 
                                        3000  (nec2dx3000.zip) 
                                        5000  (nec2dx5000.zip) 

The companion somnec2d executable has also been compiled with g77 and generates the 
nec2d.nec files necessary to utilize the Sommerfield-Norton ground in NEC2. 

These executables are made available for BETA testing. If you encounter any problems with 
these, please report the bugs. 

modified and compiled by Ray Anderson  WB6TPU  <raymond.anderson@sun.com>

nec2dx_src.zip nec2dx_src

Uploaded 4/22/2002

File nec2dx_src.zip contains the source code used to generate the nec2dx family of executables. 
The file contains: nec2dx.f, NEC2DPAR.INC, somnec2d.for, and compilation instructions 
for use with GNU g77. 

The code has been modified to allow 300 LD cards as opposed to the standard 30. Also modified 
to use non-transposed matrices in the FACTR and SOLVE routines for faster runtime. 

Ray Anderson WB6TPU  <ray.anderson@xilinx.com>

Nec2dxs.zip
nec2dxs

Updated  02/11/03

Now executes faster due to improved compile time optimization

Nec2dxs.zip contains executables (and source code) for a version of NEC2 that has the 
Somnec interpolation table generator integrated into the NEC2 executable. One of 
the advantages of this arrangement is that a new set of interpolation values is 
generated for each simulation frequency point. This leads to higher accuracy simulations 
when the effect of the ground is included. Compiled with GNU g77 and based on the same 
code used to compile the nec2dx*** series of executables. 

Works under Win 95/98/Me/NT4/2000/XP as a 32 bit windows application from a 
DOS console window. 
 
 

Contributed by the author Arie,  <4nec2@gmx.net> Neede, The Netherlands] 
 

nec2dXS_FB.zip
nec2dXS_VM.zip
nec2dXs_FB
nec2dXs_VM



Latest update 2/2/2004


nec2dXS_VM.zip recompiled with new compiler to now add
8K and 11K executables.


Special purpose versions of nec2dxs (single precision) NEC code

1) nec2dXS_VM.zip

Containing 500, 1500, 3000 and 5000 segment exe's, capable of running
virtual memory up to a segment count as indicated by the executable name,
(when when physical memory is insufficient).

2) nec2dXS_FB.zip

Containing 500, 1500, 3000, 8000 and 11000 segment exe's. To be used when
physical memory is enough to run the nr of segments as indicated by the
executable name. (Furthermore 30-60% faster with small segment counts)

Contributed by the author Arie,  <4nec2@gmx.net> Neede, The Netherlands]

vis_nec.zip
Visual NEC 
Version 1.03

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 Nec Viewer
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_Mac for Macintosh (68k)

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

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

NEC2_Mac_README.txt NEC2_Mac Readme

Document file for Mac version of NEC2 
NEC2_Mac.sea.hqx NEC2_Mac for Power PC Mac

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 NEC2_Mac for Power PC Mac Docs

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 (KG4EFO@arrl.net) 21 Nov. 2000

necfpc.zip NEC2 compiled for Power PC's w/ 32 bit reals 

This version of NEC2 uses 32 bit reals and compiles well with 
Microsoft Fortran for Powerstations. I obtained it from 
ftp.ucsd.edu /hamradio/NEC and have added the subroutine SECNDS 
for PC:s. The NEC-code at that site contained a nasty bug in a 
Hollerith string that is corrected. The subroutine ENF is commented 
away since it is not needed on PC:s. A declaration that changed a 
common area is also corrected. The resulting executable has 
been checked against a few testcases and seems to give correct 
results. The original notes and doc files is not changed. 

SM5IUF /Gunnar Isaksson 
gunis@weald.air.saab.se 
 

nec-pc.zip Note: Doesn't work under Windows XP

nec-pc 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 Note: doesn't work under Windows XP

NEC2D supplement for nec-pc

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 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_at_rd.eng.bbc.co.uk)          [ _at_ = @ ]
nec2sx.tar

nec2sx

Uploaded 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

Uploaded 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 nec2.hpux.txt
Short text file describing the changes made to original FORTRAN source code to make it run under HPUX. 
SOMNEC2D.EXE 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.







Link to Poynting Software:

www.supernec.com
SuperNEC Summary

"SuperNEC is a hybrid Method of Moment (MoM) / Unified Theory of Diffraction (UTD) antenna simulation software program based on NEC2, designed and developed by Dr Derek Nitch and Dr André from Poynting Software.
SuperNEC incorporates a 3D input and output interfaces. Bundled with additional features such as, a Genetic Algorithm optimizer, "Simply Sparse" solver core by Dr Francis Canning (patent pending) ,as well as the Sparse Iterative Method (SIM) and scripting capabilities, SuperNEC is your Complete Professional EM simulation software tool.
This electromagnetic (EM) software package is used for custom antenna design and antenna analysis among other applications
Packages vary from FREE versions to commercial packages"

Link: www.supernec.com

Note:
SuperNEC is not public domain or freeware or GPL'ed. It is a product of Poynting Software
(Pty) Ltd .
A version of SuperNEC is being made availabe for use free to academic and other non-commercial users (amateur radio operators and some others). Presently, to use this version you must have Matlab 5.3 or later installed on your system. In the future a version that does not require a separate Matlab install is planned. Contact Poynting Software at the address found on their linked web page to arrange for downloading the "free" version.

INSTYGO2.EXE YGO2 YAGI 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:


4nec2v552.zip

4nec2X552.zip

4nec2  Version 5.5.2
(updated  June 12, 2005)


( see http://www.wyger.nl/usr/4nec2/ for all the latest on 4nec2 from the author's website)
 
Changes for 5.5.2 (June 2005)
 
- Major bug fix related to GM card and European regional settings.
- Selection between multiple V/I sources for line-chart display
- Import/conversion of EZnec type input-files added.
- Display of dB value to correct with for Average Gain Test.
- Geometry builder (build.exe) now supports auto-segmentation.
- EZnec style 'MiniNec' ground-type (GN 3) added.
- Tracing/logging of SY(mbol) conversions added.
- Bug fix when using current sources with step-radius correction.
- Bug fix when changing colors for Geometry and 3D display.
- Bug fix when selecting more than 32 var's to optimize.
 
Changes for 5.5.1 (April 2005)
<><> - Far-field plot, theta angles > 360 degrees are now displayed as minus values.
- Settings are now saved again when close button is used.
- Initial azim/elev angles in optimizer are now okay.
- Gnuplot 2D/3D display for azimuth/elevation angles and labeling corrected.
- Some Nec-4 specific height- and radius tests corrected.
- Print function did behave strange sometimes, now should be OK.
- Some other small corrections and additions.


Changes for 5.5.0  (with latest bug fix as of 2/12/05)

- Now possible to use with both Nec-2 and Nec-4 (Nec4d*.exe)
- Problems resulting from XP service pack 2 discussed in the readmefirst.txt file.
- Segmentation-bug introduced with previous version 5.4.1 removed again.
- Same for bug related to GM cards in conjunction with surface patches.
- Same for zero segment/wire length bug.

Changes with 5.4.1

- Batch processing for automatic testing and calculation of multiple (4)Nec2 files.
- Extensive geometry checking added: Overlaid wires, Crossing/unconnected wires,
  Intersecting volumes, Short/thick wires at sharp angle,  Unequal segmentation
  for parallel wires, Too low hight, etc.
- Automatic convergence-testing function with line-chart result display.
- Enhanced variable-sweeper function for more easy use.
- User selectable traditional- or Eznec-style current/phase display. (also in 3D viewer)
- Screen grabber added for easy cut/paste or print parts of the screen/window/form.
- BugFix related to regional setting when generating gnuplot data-files.
- BugFix related to diplays using large resolutions.
- Few minor bugs introduced with 5.4.0 removed.


Changes with 5.4.0


- Automatic generation of L, Pi and T matching-networks (low- and high-pass)
- Plot 2D and 3D graphs/charts using gnuplot freeware package
- Show Circular Polarization components E(left) and E(right) for far-field.
- Use of Symbols when creating file with geometry editor to be able to optimize design.
- Autosegmentation/Stepradius bug on Windows-XP removed.
- At one place, feet was .3058 instead of .3048 meters.
- Some other minor things changed/fixed/improved.

Changes with version 5.3.9
Incorporates several minor bug fixes.

Changes with version 5.3.8
Incorporates  bug fixes to alleviate problem with saving files without
extension.

It is  now possible to specify insulated wires using an optional LD7
type loading.

Changes with version 5.3.7
Incorporates various minor enhancements and bug fixes.

Changes with version 5.3.5
Incorporates various minor enhancements and bug fixes.

Changes with version 5.3.4
Incorporates miscellaneous bug fixes for problems found in earlier rev.

Changes with version 5.3.3
Incorporated several minor bug fixes and one  major bug fix associated with
Windows 2000. Several minor enhancements added.

Note: when installing, be sure to first install the 4nec2v533 package before
installing the 4nec2X533 package. (These are to be installed in the same directory)

Changes with version 5.3.2
Minor bug fixes incorporated

Changes with version 5.3
Supplementary DLL and DirectX files files included in install file.
Drag and Draw support added for CM, GW, GS, FR, TL and GN cards
in the antenna geometry editor. Ability to use non-metric units added.

Changes with version 5.2
Added ability to display surface patches. Minor bug fixes implemented.
 

Changes with version 5.1

- Additional optimizer based on genetic algorithms added. 
- Optimization for both single-frequency or band-of-frequencies. 
- More general and consistent data-entry when generating nec-2 output. 
- Pre 4.3 version support for raw nec-2 input re-enabled. 

The new 5.1 4nec2X version also enables real-life structure-geometry 
and far- or near-field pattern visualization. The use of DirextX based 
hardware graphics-acceleration delivers you fast rotating, zooming 
and moving of the more complex structures or patterns. 
(Click here to view some sample  screendumps)
To use this eXtended version, please download both the 4nec2v**.zip 
and 4nec2X**.zip files, and read the _ReadMeFirst.txt file for further 
instructions. 

To support all those not having state-of-the art computer systems or 
uncommon graphics hardware the standard 4nec2.exe is also available. 

4nec2v51.zip  Basic 4nec2 installation (updated 01/10/03)
4nec2X51.zip  Addition for DirectX based version (updated 01/10/03)
 

4nec2 is a user-friendly layer around the standard nec-2 engine. 
The 4nec2 package contains all the software to specify, calculate, 
evaluate and optimise your antenna-system.  It also incorporates the 
nec2dxs**** executables that integrates  NEC2 and SOMNEC into 
the same executable. 
Some of the default 4nec2 capabilities: 

- 2D and 3D geometry-structure, current, far- and near-field display 
- Both a 'hill-climbing' and a Genetic-algorithm based optimizer included. 
- Capable of modelling nec-2 files up to 11.000 segments 
- Compare up to 5 different far-field plots in one view 
- SWR, Gain, F/B, F/R, Z-in, X-in frequency-sweep graphs 
- Optional use of variables, constants or equations in nec-2 input file 
- Flexible antenna evaluator and structure validator 
- Support to use current-sources within nec-2 definition 
- Smith-chart display with integrated line-length calculator 
- VOACAP, ICEPAC, REC533 type-13 and -14 antenna-file generation. 
- Automatic area-coverage evaluation and viewing using VOACAP/ICEPAC. 
- Geometry-builder include in the package 
 

Changes with version 5.0

- Real-life 3D viewer added using hardware-acceleration 
- Nec2dXS for increase number of LD, EX and NT/TL cards. 
- Max number of near/far-field increased to 200000 
 
 
 

Contributed by the author Arie, <4nec2@gmx.net> 

 

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 jgraps
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.boye_at_rd.eng.bbc.co.uk)     [ _at_ = @ ]
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>


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

MultiNEC.zip

MultiNEC

Version 2.2.2 uploaded 1/19/2005

Uploaded 2/25/2003

MultiNEC is a combination Excel and Visual Basic program that can automate
the repetitive steps of antenna modeling.  You can build your model via the
user interface or import existing EZNEC, NEC, Antenna Model (Teri Software),
ELNEC, MMANA, AO, or Nec/Wires format models.  MultiNEC can then calculate
the results for a given scenario or can run multiple test cases while
automatically changing the model between runs.  Output is available in
tabular numeric format and in several different chart and plot formats.

You can also show the expected propagation performance of your antenna.
Propagation predictions are made via a simplified interface to the VOACAP
engine and may be presented on both area coverage maps and point-to-point
plots.  You can animate these maps and plots to easily see how the
propagation might change given varying ionospheric conditions or as a result
of changes to the model.

MultiNEC can be used by itself if desired or it can be used to extend the
capabilities of other antenna modeling programs.  For more information and
downloadable user manuals see www.qsl.net/ac6la/.  Requires Excel 97 or
later.

Important:  You must allow Excel macros to be enabled or none of the
MultiNEC buttons will work.  If you click a button and see small white
squares appear around the perimeter of the button face, as opposed to seeing
the expected button response, it means that you must make an easy, one-time
change to your Excel settings.  Please see the ReadMe file for more details.

Submitted by the author Dan Maguire  AC6LA (ac6la@arrl.net).

 

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

ncsarsim.zip
ncsarsim

Uploaded 5/20/04


ncsarsim.zip  contains routines to use NEC to simulate synthetic
aperture radar imaging of a scene containing a target in some state of motion.
Various states of motion, including rectilinear translation, vibration,
and rotation, are considered, as well as superpositions of such
motions.

NCSARSIM is a program to control the operation of the method-of-moments
program NEC to simulate SAR imaging of a target that is moving in some
fashion. (It can handle the case of no motion too.)


contributed by the author  Glenn Stumpff <gstumpff@yahoo.com>
nec_docs_order_info.txt Provides info on ordering official NEC2 documentation from the government. (updated 12/29/98)
nec_exe2.zip nec.exe version 2
New Version updated 5/15/02

nec.exe version 2 is now available for download. 

This new version superceeds the earlier version of nec.exe. The new executable 
has been tested on Windows XP and uses the Windows 32 bit console program mode. 
The associated source code should also be easier to port to Unix or Linux where the 
obvious compiler of choice would be gcc. I would welcome feedback from anyone who 
anticipates compiling it for a Unix or Linux platform. 
-------------------------------------------------------- 

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.) 

(contibuted by the author Ralph Holland , VK1BRH <ralph@arising.com.au> 
< http://www.arising.com.au/people/Holland/Ralph/index.htm >

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_at_rd.eng.bbc.co.uk)   [ _at_ = @ ]
nec2pp_1.2.tar nec2pp

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

New Version uploaded 6/18/2004


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, GM, GX, and GR cards as well as support for VGA
graphics. It has the capability to print out (in monochrome) the
displayed NEC structure (see PRINT.NV) and to output a PCX file
(see PCX.NV), or as of 13 June 2004, a BMP file (see BMP.NV). Also as
of 13 June 2004, it will now handle NEC input files that store multiple
structures, displaying each structure one at time. It now also works
with NEC4 input files. The archive also contains a special version of
NVNEW--NVCOMP. It displays the geometry in a lefthanded coordinate system
(see NVCOMP.TXT).

Glenn Stumpff
gstumpff@yahoo.com



Pointer to on-line docs (http://www.nec2.org) link updated 9/15/03

On-line NEC2 manual at URL http://www.nec2.org
(in .html, .pdf, and .doc formats) 

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

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 Docs

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

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

"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

W5GFE_toolkit_python_port.tgz
Python port of W5GFE NEC Antenna Toolkit

Uploaded January 16, 2004


 README - Python port of W5GFE NEC Antenna Toolkit

These Python scripts are a port of the Perl/Tk antenna toolkit developed by W5GFEfor analysis of NEC2 files.

The azimuth and elevation plotting scripts include a version Azimuth(Mac).py and Elevation(Mac).py, respectively that use the Mac file system routines to open files, rather than the Python file methods.  Otherwise the scripts Azimuth.py and Elevation.py and  Azimuth(Mac).py and Elevation(Mac).py, respectively, are the same.  They have been tested on Classic Mac (OS 9.1) and Windows (2000 and NT).  Other than the two Mac-specific scripts noted above, these scripts should be platform neutral.

The function of the Python scripts is the same as the corresponding W5GFE tools. This README file is intended to
supplement, not replace, the original documentation included in W5GFE's toolkit distribution. To facilitate use of these tools, copies of Bill's descriptions have been included with permission, which is greatly appreciated.  These have been included as the original .pod documents, a Mac SimpleText document (no file extension), and a generic text file (.txt extension) which should be viewable using any text editor, possibly with line separator translation.  (The generic text documents have Unix line separators.)


A Python interpreter with the Tk module installed is required.  Mac OS 9 users should use MacPython 2.2.3 as the last Mac port of Python for Mac OS 9, Version 2.3 apparently does not include the Tk module.  A Tcl/Tk executable also needs to be installed if not included in the Python installation, or otherwise installed on your system.

The scripts and this document are copyright 2003 by Barry S. Newberger, W5KH.
XLNEC.zip NEC.XLS

Latest rev uploaded 7/12/2002

(copy uploaded 6/27/02 possibly corrupted)

NEC.XLS 

Updated version VB1.10 (1/12/99) now online.
(6/27/02 set up for easier first time use)

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

RF3.zip

RF4.zip
 

RF1, RF, RF3, RF4.xls

Updated 7/12/2002

(copy uploaded 6/27/02 corruped during transfer)
 
 
 

RF1, RF, RF3, RF4.xls (Release 5.00, 28/02/02) 
 These MICROSOFT EXCEL workbooks form a companion to the completely free automated NEC design 
package which is publically released on this site as XLNEC.ZIP, and contain practical modules for solving 
formula and chart related RF problems of interest to antenna builders. 
 The original RF1 and RF2 workbooks  have  been re-organised into four books of  appropriate groupings, errors 
corrected, and new sheets added. 
RF1.XLS contain propagation related worksheets. 
RF2.XLS brings spreadsheet assistance to impedance measurement and matching. 
RF3.XLS contains  pages related to antenna design and building. 
RF4.XLS solves many of the more general problems met in the RF workshop. 


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'! 
 

.. As previously, absolutely free, from the workshop of 
                    Peter Ward, AX2VCI.  Bairnsdale, Victoria, Australia 
                    pward@net-tech.com.au 
 

 

xnecview-1.0.tar.gz XNECVIEW

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. 

SPECIAL  COLLECTION:
 DL5SAY Collection (uploaded 1/14/02)

The materials contained in this directory may be of some use to the 
amateur community.  They also represent a remarkable work of love 
and devotion on the part of XYL Ursel Kreh, wife to 
Hartmut Hans Kreh DL5SAY, who died in January 2001, aged 54. 

I offer them, through the courtesy of Frau Kreh, to the Amateur 
Community.  Please direct any correspondence to: 

        Bill Walker W5GFE 
        bw@cs.ecok.edu 

        Professor and Chairman 
        Department of Computer Science 
        East Central University 
        Ada, Oklahoma