----- Original Message -----
From: "Rob Atkinson, K5UJ" <k5uj@hotmail.com>
> There is a lot of incorrect information out there on this topic that can
> mislead hams, especially new ones. Only a month ago, QST no less,
> published
> an article on an inverted L antenna for 160 m. in which the author wrote
> that any number of radials, even a few is okay. This is frankly not true.
> I was amazed that the editors of QST would publish such a statement but
> they
> did. Here is a direct quote from the article on p. 55 of the Feb. 2007
> 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!"
>
> Perpetuating this sort of "anything works" attitude only leads to more
> hams
> operating with poor signals that the rest of us must either work to copy
> or
> give up on.
I hope my previous post didn't come across that way, Rob, as that wasn't
my intention. I think, however, there is some truth to what was stated in
the
QST article. Because of the vagaries of soil properties anything MAY work.
Let me explain. I have a friend here in Los Angeles who has worked DXCC
on 160 meters from a small city lot (not easy from out here). He shunt feeds
his tower and feeds it against exactly ZERO radials. Given convential
wisdom,
I would expect him to be puny weak. He isn't. He consistently smokes me in
pileups despite the fact that I have thousand of feet of radials and
everything
but the kitchen sink tied into my ground system:
http://www.dellroy.com/W4EF's-Ham-Radio-Page/Radial_Project/Radial.htm
For a while, I thought perhaps he was running a big active antenna tuner,
but as it turns out he is running pretty much the same amplifier that I am
now running. He still beats me out, and many times, he works stuff and I
just
don't get through at all. Now maybe I am just a big LID, but I'd like to
think
there is another explanation. His house is built on top of an old golf
course
on very rich soil in a low plain area whereas I am on the side of a mountain
on very dry rocky soil. In my case, as many radials as possible are an
absolute
must whereas in his case, he seems to do pretty well without them. I seem to
be
doomed to live in areas where radials are needed. When I was in Florida my
Marconi antenna was a dummy load until I put a bunch of radials under it.
OTOH, per the FCC map, the old KS8S/AD8P station was right in the middle
of an exceptionally high ground condunctivity countour in NW Ohio. Those
guys
were LOUD (hence my cynical remark about the rusty ground rod). We used
to bust in over the east coast guys routinely from that QTH. It was rich
farmland,
and the water table was really close to the surface. Because of these
observations (and many other similar ones) I strongly believe that ground
properties make a huge difference as to how many radials are needed for an
optimum system. Thus when someone asks how many radials are enough for
a given installation, you can't really give a good answer unless you know
something about their soil properties.
I think the point of the QST article is that don't be discouraged if you
don't
have 10 acres where you can lay out 120 1/2 wave radials. Do the best you
can with what you have and you may be pleasantly suprised at how well it
works, or you may be perpetually discouraged (kind of my situation here at
my present QTH). Heck I know a guy in a CCR area that puts a 30' mast
on the back of his pickup truck and droops the a top-hat wire across his
house to get on 160 meters. He uses a 1 radial counterpoise and 500
watts, and I'll be darned if he doesn't have a consistently decent signal on
160 meters.
>I for one would like for as many hams as possible to know how
> to put up good antennas so they have good signals and are a pleasure to
> work. Basic topics such as radials are therefore worth revisiting so
> these
> myths are put to rest if possible. If you find your patience being taxed
> by
> these messages then I ask you to please tolerate those hams such as
> myself,
> who started the whole thread, while we try to learn something, instead of
> attempting to squelch this discussion with a splenetic, cantankerous
> summary
> of the topic as you see it. It will probably run its course soon anyway,
> if
> it has not already.
>
> 73,
>
> rob / k5uj
Finally, by all means lets keep discussing theoretical methods to determine
what is optimum for a given situation, but I think it is a harder problem
than
most imagine. Keep typing, I just read what interests me and ignore the
rest.
73 Mike, W4EF.....................................
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