SM 5 BSZ - Computer Program For Yagi Optimisation Using Piecewise Linear Current Approximation
(May 05 1997)


This computer program is available in some different sizes. If you have an old PC with 80286 or older, YOLIN36.ZIP(44k) contains the EXE file that will work (slowly) for you. YOLIN36 needs 550k of free ram. Of course this 16 bit program will work on any computer, but if you have a 386 or better, YOLIN96.ZIP(78k) or YOLIN230.ZIP(78k) are faster versions. The latter ones use 32 bit FORTRAN, and they require DOSXMSF.EXE.

The digits at the end of the file names represent the maximum number of elements that can be handled by each program. If you do not have enough ram memory, the 32 bit programs will use your hard disk, and then the computing speed becomes extremely slow.

To run these programs, the following files are needed (click for examples):

INPUT.YAG This file contains the start geometry in the same format as the one used in YO by K6STI. The first line is a comment line. The second line is the operating frequency. One or 3 numbers followed by "MHz". If 3 frequencies are given, they are used to control step size and step width if frequency stepping is selected. The third line is number of elements followed by "elements" and "millimeters" or "inches" as desired. The fourth line is the element diameter. Then comes one line for each element, position along the boom followed by half the length.

MODE.DATThis file just contains a digit that orders the program what to do:
0 = Optimize - output file is BSZ.YAG
1 = Calculate for different frequencies /controled by INPUT.YAG/ - output file is FREQ.DAT
2 = Calculate for different stacking distances /controled by CONFIG.DAT/ - output file is STACK.DAT
3 = Calculate gain and get integrated pattern - output file is PATTERN.DAT

WEIGHTS.DATThis file contains numbers used as weights for some extra equations in the least squares fit and a desired value for the feed impedance. Note that the numbers are position sensitive, 10 columns for each floating point number. The numbers are in order:
1 (EFFIC) Weight for equation reducing ohmic losses.
2 (Z) Weigth for equation reducing deviation from desired input impedance.
3 (BACK) Weight for equation reducing back lobe (at 180 degrees)
4 (XZ) Weight for equation reducing boom length divided by gain.
5 (ZNOM> Desired value for feed impedance.

CONFIG.DATThis file contains stacking information. The two first columns of the first line is the number of antennas to stack. The first line also contains 4 floating point numbers, the first of them is the unit of length for the stacking geometry. The last 3 are initial value, final value and step size used if MODE.DAT was 2. The following lines are stacking coordinates.

In each file some extra lines are added after the ones read by the program. These lines give the same info as this page.

Calculations produce files with ext .dat

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