Rob - I share your concern with QST's cavalier attitude toward
radials. The real problem with statements such as those in the
February QST:
"For verticlal radiators (including slopers), lay out radials if you
can --
one or more of any length and configuration. Don't be discouraged if
you
hear that anything less than (take your pick: 25, 50, 120 and such)
will be
useless. Baloney,! Try whatever you can --- even none!"
is that they encourage hams, particularly new ones, to put up
antennas without thinking about how they work or about their overall
performance.
And this is particularly bad with verticals, where enough silicon oil
has already been spread.
I can't imagine giving advice to try a vertical without some thought
to radials. There is a noticeable improvement in even adding a single
radial to a groiund rod only sustem. The ham that uses 4 quarter wave
radials would be much better off putting that 1 wavelength of wire
down as 10 one tenth wave radials.
To encourage this cavalier attitude as to the role of radials in a
vertical antenna essentially says that we should ignore half of the
antenna system. I don't suppose that QST would publish an article on
how to build a dipole where only one side of the dipole needed to be
measured accurately. Yet they accept that kind of thinking for
vertical antennas.
The role that radials play in vertical antennas is not a difficult
concept to grasp and it could be relayed in a paragraph or two. Once
one understands that the ground and hence the radials are actually
part of the antenna and contribute to teh overall antenna efficiency,
one has a much better idea of the importance of the ground and what
to use for radials. If the author did not want to address these
issues he could point to several useful references that have been
published in QST over the years. - Dr. Megacycle KK6MC/5
--
James Duffey KK6MC/5
Cedar Crest NM 87008
DM65
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