NAME

       first - Yagi-Uda project quick antenna builder

SYNOPSIS

       first filename  elements f_min f_design f_max f_step diameter

DESCRIPTION

       The  program  first  is  one  of  a  number  of executable programs that forms part of a set of programs,
       collectively known as the Yagi-Uda project , which were designed for analysis and optimisation  of  Yagi-
       Uda  antennas.   first  is  used  to  define an antenna quickly, if you are not interested in analysing a
       specific design (in which case use input ) but need to get a design that is half-way reasonable  so  that
       it  may  be  optimised.  It  is  much  faster  in  use  (since its not interactive) than input The design
       methodology that first is the DL6WU antenna designs, which are valid for 10 or  more  elements,  although
       first  will  calculate for any number of elements. DL6WU reccomends a folded dipole, but the designs here
       are for a simple dipole, since I don't yet know how to calculate the self and mutual impedances of folded
       dipoles.

LIMITATIONS

       Filenames, including full path, can't exceed 90 characters.

       Does  not  take into account the variation of impedance of a dipole with change in wavelength/diameter of
       elements.

FILES

       filename          Yagi description, created by first.
       filename.out      Binary data file, created by yagi.
       filename.dat      Performance of antenna, created by output.
       filename.gai      Gain of antenna, created by output.

       The DOS .EXE files as distributed require a 387 maths coprocessor to be present and will not run  without
       it. A 486, Pentium, and I assume later processors of this series will run it without any extra hardware.

PLATFORMS

       Both  DOS  and and Unix versions have been built. The DOS version as distributed requires a 386 PC with a
       387 maths coprocessor. The DOS version is no longer being developed, so the DOS executables included with
       the distribution are not upto date with the current source code.

AUTHORS

       Dr.  David  Kirkby  G8WRB  (david.kirkby@onetel.net).   with  help  with  the  conversion  to  the DOS/PC
       environment from Dr. Joe Mack NA3T (mack@fcrfv2.ncifcrf.gov)

SEE ALSO

       input(1), output(1), yagi(1), optimise(1).

BUGS

       Bugs should be reported to: David Kirkby G8WRB (david.kirkby@onetel.net).  Bugs tend actually to be fixed
       if  they  can be isolated, so it is in your interest to report them in such a way that they can be easily
       reproduced.

       If the input file is edited manually and done incorrectly, there can be unpredictable results.

       Options are not checked for sensible numbers. A negative length can be entered!