Provided by: yagiuda_1.19-2_i386 bug

NAME

       output - Yagi-Uda project antenna display program

SYNOPSIS

       output [ - cehps ] [ -EE_max ] [ -HHmax ] [ -rminimum ] [ -Rmaximum ] [
       -ZZo ]

       filename

DESCRIPTION

       The program output 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.
       output  calculates  the  gain,  FB ratio, input impedance etc etc of an
       antenna that was described by the program input or first  and  has  had
       the  element  currents  calculated with the program yagi The data about
       the forward gain, VSWR, FB ratio, input impedance etc is written  to  a
       file filename.dat Angular data, giving the variation of gain with theta
       and phi is put into a file filename.gai
       Sometimes the program fails to find the 3dB bandwidths in the E  and  H
       planes, and bombs out with a ’zbrent’ error. This can occur if:
       (1)  The  antenna  has  an  almost isotropic pattern, in which case its
       never 3dB down, so the 3dB point is undefined.
       (2) The 3dB point is outside the assumed angular range.  You then  have
       to either:
       (a)  Calculate  with the -e option, which avoids calculation of the 3dB
       E-plane beamwidth or
       (b) Do (a) above, then find approximately where the 3dB point is  (from
       the  .gai  file  -see later), then set options -E and -H so the program
       calculates them properly.

       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.  The
       DOS  files  are no longer being maintained, so are out of sync with the
       latest source.

OPTIONS

       -c     Calculate the maximum level of any sidelobe - not just the  rear
              on  as  the  FB ratio tells us. If the sidelobe and FB ratio are
              equal, it means the biggest sidelobe is the  rear  one.  If  the
              Sidelobe  is  less  than the FB ratio, then another lobe is more
              significant. Look in the ’.gai’ file (see below) to see where it
              is. This option slows the program quite a bit.

       -e     Suppress  calculation  of  the  3dB  E-plane  bandwidth. This is
              sometimes necessary if the programme is unable to find the 3  dB
              beamwidth, to prevent an error occuring.

       -h     Suppress  calculation  of  the  3dB  H-plane  bandwidth. This is
              sometimes necessary if the programme is unable to find the 3  dB
              beamwidth, to prevent an error occuring.

       -p     Put data into a file filename.freq for reading into gnuplot, and
              a commmand file filename.gc for gnuplot to use. (run ’output  -p
              filename’ then ’gnuplot filename.gc’ )

       -s     Suppress  all  diagnostic  output. By default, the program print
              the percentage of the job completed.

       -EE_max
              When the program computes the E-plane 3dB beamwidth, it  assumes
              the  antenna  pattern  is  3dB down somewhere in the range 90 to
              Emax, where E_max is by default 179 degrees. This can fail if it
              is never 3dB down in the range, or if it happened to go 3dB down
              in two or more points. You can change E_max, if you need to, but
              rarely  if every should need to. I’ve never seen a failure here,
              but are guarding against one. If you dont want the pattern,  use
              the -e option instead, which skips it. See also ’-H’ below.

       -HH_max
              When  the program computes the H-plane 3dB beamwidth, it assumes
              the antenna pattern is 3dB down somewhere  in  the  range  0  to
              Hmax,  where H_max is by defualt 60 degrees. This can fail if it
              is never 3dB down in the range, or if it  happended  to  go  3dB
              down in two or more points. Also, if it goes more than 3dB down,
              but that starts to come up again. You can change H_max,  if  you
              need to, as failures do occasionally occur. If you dont want the
              pattern use -h option instead, which will skip it.
              An obvious example of an antenna where you  cant  find  the  3dB
              bandwidth  for  the H-plane is the 1ele dipole. The radiation is
              symmetrical about its axis, so the level is the same  everywhere
              in  the H plane. The program automatically avoids calculating it
              for a 1 ele beam.

       -ZZo   Zo is the characteristic impedance  used  when  calculating  the
              VSWR.  By  default it’s 50 Ohms, but can be changed to any real,
              positive value.

        filename
              is the name of the file containing the antenna  description.  It
              is  expected  to  be in a format created by input or first - two
              other programs in the Yagi-Uda project.  The is also expected to
              exist a binary file filename.out created by typing yagi filename

Limitations

       I’m not aware of any limitations, apart from that filenames,  including
       full path, can’t exceed 90 characters.

FILES

       filename        ASCII file with antenna description.
       filename.out    Binary data file, created by yagi.
       filename.dat    ASCII file with gain, FB ratio etc.
       filename.gai    ASCII file with angular dependence of gain.

SEE ALSO

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

PLATFORMS

       Both  DOS  and  Unix  versions  have  been  built.  The  DOS version as
       distributed requires a 386 PC with a 387 maths coprocessor.

BUGS

       Bugs should be reported to 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.   The
       program  gives errors if element lengths are well away from a half-wave
       (by a factor of ~3) due to a breakdown in the equations.  If the  input
       file   is   edited   manually   and  done  incorrectly,  there  can  be
       unpredictable results.

AUTHORS

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