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FIRST(1)		    General Commands Manual		      FIRST(1)

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 de-
       sign  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 dis-
       tributed	requires a 386 PC with a 387 maths coprocessor.	The  DOS  ver-
       sion 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  enviroment	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@one-
       tel.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!

Version	1.10			Fri Dec	 2 1994			      FIRST(1)

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