A free, open-source tool for calculating non-redundant values of segs/wavelength.
In re-segmenting an AN-SOF or NEC model, small changes occasionally clone an exactly identical file. Take, for instance, the model below, segmented at 13 and 18 segments-per-wavelength for 5.332 MHz.
They are exactly identical! The same would occur were I to have segmented it at 14, 15, 16, or 17 segs/WL. Not until 19 segs/WL will the above model change at all for 5.332 MHz.
Herewith I provide a means to avoid wasteful trial-and-error by discovering beforehand which segmentations produce unique models. One then may proceed to explore model convergence in an efficient manner.
My free, open-source program works on both Windows and Linux like so.
KY8D_NEC_Segs.exe into any directory containing one or more *.nec filesKY8D_NEC_Segs.exe../segs_per_wavelength.txt
KY8D_NEC_Segs.pl into any directory containing one or more *.nec filesperl KY8D_NEC_Segs.pl../segs_per_wavelength.txt
In NEC decks, it is strangely allowed for plural GS (Geometry Scaling) cards to be present. Almost never does anyone do this, as it would exert a cascade effect. Each succeeding GS card would then re-scale all prior scalings before it. My program therefore anticipates no more than a single GS card to be present, if any. If plural are found, all but the final will be ignored, with it alone exerting universal effect. This ought to be no problem at all.
A 5.6m vertical can indeed be used at 5.332 MHz. I employ just such a vertical in conjunction with an LDG RT-100 remote auto-tuner for portable work. This real-world antenna easily covers 10m through 60m, WARC included.
Link: Camera Tripod Vertical
Below is an example output file. Shown is the result of running KY8D_NEC_Segs.exe in a directory containing a single *.NEC file. Had there been plural files, all would have been parsed.
Non-redundant segments-per-wavelength. File = 36-radial_vert.nec GW lines tally = 74 Unique lengths (m): 0.100, 5.500, 2.460, 8.888 Freq = 5.332 MHz Segs/wire @ 10/wl: 1, 1, 1, 2 Segs/wire @ 11/wl: 1, 2, 1, 2 Segs/wire @ 13/wl: 1, 2, 1, 3 Segs/wire @ 19/wl: 1, 2, 1, 4 Segs/wire @ 21/wl: 1, 3, 1, 4 Segs/wire @ 23/wl: 1, 3, 2, 4 Segs/wire @ 26/wl: 1, 3, 2, 5 Segs/wire @ 31/wl: 1, 4, 2, 5 Segs/wire @ 32/wl: 1, 4, 2, 6 Segs/wire @ 38/wl: 1, 4, 2, 7 Segs/wire @ 41/wl: 1, 5, 2, 7 Segs/wire @ 45/wl: 1, 5, 2, 8 Segs/wire @ 46/wl: 1, 5, 3, 8 Segs/wire @ 51/wl: 1, 5, 3, 9 Non-redundant segs: 10, 11, 13, 19, 21, 23, 26, 31, 32, 38, 41, 45, 46, 51 Freq = 7.035 MHz Segs/wire @ 10/wl: 1, 2, 1, 3 Segs/wire @ 15/wl: 1, 2, 1, 4 Segs/wire @ 16/wl: 1, 3, 1, 4 Segs/wire @ 18/wl: 1, 3, 2, 4 Segs/wire @ 20/wl: 1, 3, 2, 5 Segs/wire @ 24/wl: 1, 4, 2, 6 Segs/wire @ 29/wl: 1, 4, 2, 7 Segs/wire @ 31/wl: 1, 5, 2, 7 Segs/wire @ 34/wl: 1, 5, 2, 8 Segs/wire @ 35/wl: 1, 5, 3, 8 Segs/wire @ 39/wl: 1, 6, 3, 9 Segs/wire @ 44/wl: 1, 6, 3, 10 Segs/wire @ 47/wl: 1, 7, 3, 10 Segs/wire @ 48/wl: 1, 7, 3, 11 Segs/wire @ 52/wl: 1, 7, 4, 11 Non-redundant segs: 10, 15, 16, 18, 20, 24, 29, 31, 34, 35, 39, 44, 47, 48, 52 Freq = 10.125 MHz Segs/wire @ 10/wl: 1, 2, 1, 4 Segs/wire @ 11/wl: 1, 3, 1, 4 Segs/wire @ 13/wl: 1, 3, 2, 4 Segs/wire @ 14/wl: 1, 3, 2, 5 Segs/wire @ 17/wl: 1, 4, 2, 6 Segs/wire @ 20/wl: 1, 4, 2, 7 Segs/wire @ 22/wl: 1, 5, 2, 7 Segs/wire @ 24/wl: 1, 5, 2, 8 Segs/wire @ 25/wl: 1, 5, 3, 8 Segs/wire @ 27/wl: 1, 6, 3, 9 Segs/wire @ 30/wl: 1, 6, 3, 10 Segs/wire @ 33/wl: 1, 7, 3, 10 Segs/wire @ 34/wl: 1, 7, 3, 11 Segs/wire @ 37/wl: 1, 7, 4, 12 Segs/wire @ 38/wl: 1, 8, 4, 12 Segs/wire @ 40/wl: 1, 8, 4, 13 Segs/wire @ 44/wl: 1, 9, 4, 14 Segs/wire @ 47/wl: 1, 9, 4, 15 Segs/wire @ 49/wl: 1, 10, 5, 15 Segs/wire @ 50/wl: 1, 10, 5, 16 Non-redundant segs: 10, 11, 13, 14, 17, 20, 22, 24, 25, 27, 30, 33, 34, 37, 38, 40, 44, 47, 49, 50
Version 2025-01-03 an update to disallow segment length < 3 wire diameters
*.exe for Windows; and also the *.pl source code. ZIP archive software (like 7-Zip ) for the extraction.Latin for “Let the moocher beware”. I designed this for me, and used it with glee. I share it here with you for free, but offered without even so much as the smell of a dead warrantee (or wheriot, as the case may be). Whatsoever disasters of cosmic proportion as may result from the use of this program, any and all culpability rests wholly and solely with the user.