For all practical purposes, a vertical with only one radial doesn't have
"gain" in one direction ... it merely has more loss in all other
directions. That may be useful if you need enough pattern to give you
discrimination in directions away from the radial due to QRM or QRN, but
it won't make you heard better than if you had radials in all directions.
I assume, however, that one of the articles you read was the one by
K7BKI in the latest issue of QST. That antenna really isn't as much a
vertical antenna with radials as it is a vertically polarized V-antenna
(which could theoretically offer some slight gain) since he has it
mounted 13 feet off the ground. Even in that case, though, take a look
at the max gain numbers in the EZNEC plots he included in the article
... 1.37 dbi is hardly what I would call "gain" over a traditional
vertical antenna, and at the takeoff angle of maximum F/B it's only 0.9
dbi. Personally, I think it was misguided of him to attribute his newly
improved ability to work DX to that antenna unless his previous yagi was
defective ... 30m isn't even the same band he was operating before.
But to answer your question, yes ... ARRL <is> pretty much publishing
just anything now and several of their articles over the last few years
have been technically misleading or even just plain flawed. I'd bet
that their editorial review process consists solely of grammar and context.
73,
Dave AB7E
On 5/12/2011 12:23 PM, Tom Osborne wrote:
> Blank
> Hi All
>
> In the past 2 months, I have seen two different articles in ARRL
> publications that say a vertical with 1 radial has gain in the direction of
> the radial. One said 3 db. Evidently Eznec confirmed this.
>
> Why the heck do I bother putting down all those radials under my verticals??
> According to one article, 1 radial is best because it gives the antenna a
> real wide bandwitch, SWR is close to 50 ohms, and has gain in the direction
> of the radial. Seems like those symptoms would give loss not gain.
>
> Is this true, or is the ARRL just publishing anything now? Sure is
> different from anything I've ever known about verticals.
>
> Seems like I should be able to put up an antenna with 1 radial on my rotor
> and I could point it just like a beam. Fill me in. 73
> Tom W7WHY
>
>
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