See April 1994 QST pages 32-34.
An interesting concept is presented here, a series of 2 element wire yagis,
that model quite well.
EZNEC shows >8dbi gain, >36db f/b with 0.133 wavelength spacing. Looks
good, but the formula in QST seems flawed. Using the 269.1/fMhz for length
of half the reflector plus length of support looks good, and sounds good.
However, using this formula clearly affects the element spacing, and is an
important consideration. More importantly, using the formula given the
driven element would never fit within the dimensions of the third leg of the
triangle.
I have duly noted the date of issue of the QST. I have modeled the aerial
(ignoring the formulae) in QST with attractive results. Will it work as
advertized (by EZNEC), or is the software fooled by the date of issue too?
SeventyThreesAndBackToNetOverOver,
Bob.
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