[Elecraft] RE: verticals...........

Sat Feb 9 17:21:30 2002

Thanks.  My main interest for the vertical is for the bands higher than 30M.
The lower angle radiation is the attraction.  So for any use, the vertical
would be for DX.  However, the kicker is that I do not think I can put in a
counterpoise system (at least where it is located now).  I do not think I
would have the room for it.  So for lower band stuff, my dipole would be
used for that.

BTW... On my current dipole, I contacted the Bahamas from here in Ohio on
160Meters with lower power. (CW, of course!!).  Reason for the low power is
because when I go on 160 Meters, it gets into the computer speakers here in
the shack.

<getting on my QRP soapbox>
A couple of nights ago, I was operating the IC706 and PSK31.  Contacted a
gentleman in Texas.  I had a good signal to him.  He was running 245 watts
into a Log periodical.  I was running 5 watts.  It was fun to let him know
how much power I was running.  Of course, his antenna probably helped him
copy me well.
<getting off my QRP soapbox>

PSK31 seems to be a great QRP mode.  CW is probably my main operating mode,
with PSK31 becoming a close second.

Thanks...

Jason

----- Original Message -----
From: "Eddy Avila" <[email protected]>
To: <[email protected]>
Sent: Saturday, February 09, 2002 4:28 PM
Subject: [Elecraft] RE: verticals...........

> Ron, your points are well taken the best I've ever read about performance
> differences between verticals and simple horizontal antennas....you must
do
> this for a living? If not....you should!!
>
> I completely concur with Ron based upon my experiences with both types of
> antennas! I installed a Butternut hf2v last summer and it generally has
> worked much better than my 20-foot off the ground horizontal dipole for
> 80/40.
>
> Jason, the only thing I can add to Ron's recommendations is that if you go
> the vertical route you must be willing and able to install a good
> counterpoise ground system otherwise, don't bother, especially for 80
meters
> cuz most of your power will go to heat the ground surrounding the
> vertical....anyway, that's been my experience and reading on the
subject...
>
> 73....../k6sdw
>
>     Jason wrote:
>
> >Anyways, on to my point... I wanted to know what kind of performance you
> >can get with a vertical.
>
>
> Ron D' Eau Claire wrote:
>
> Verticals work GREAT! Marconi spanned the Atlantic with one.
>
> Comparing a simple vertical with a simple horizontal antenna there are two
> significant issues. Who do you want to reach, and how high can you put the
> horizontal?
>
> If your over-riding concern is to have the most uniform low angle
radiation
> pattern with no directivity, the vertical is the best choice if it is
> installed "in the clear" where there are no nearby objects to interfere
> with
> its pattern.
>
> If you want maximum signal for DX and can get the horizontal up 0.3
> wavelengths or more above the ground, the horizontal will significantly
> out-perform the vertical. The horizontal interacts with the ground to
> produce "gain" in its major lobes when it is high enough. It will show
some
> directivity (although, contrary to some beliefs, it is never zero in any
> direction in a real antenna).
>
> But if you cannot get the horizontal up that high (about 40 feet on 40
> meters or 80 feet on 80 meters) the vertical usually will do a better job.
> That's why verticals are so popular on 80 and 160 meters and pretty common
> on 40: many of us cannot get a horizontal up far enough on those band to
> get
> any advantage over a vertical. Indeed, if the horizontal is low enough, a
> vertical will outperform it with low angle radiation.
>
> If you want to work short skip and locals (beyond a few miles) a
horizontal
> will usually do much better. A vertical has less radiation at high angles
> than a horizontal. The higher angle radiation from the horizontal produces
> stronger short-skip and local signals. That's why some ops who like to
work
> short skip purposely install a horizontal antenna at a low height. They
are
> called "cloud warmers" and produce very consistent and strong short skip
> signals.
>
> It's hard to beat a vertical for its relatively small "footprint" and ease
> of installation, and it's hard to beat the extra gain of a horizontal at a
> decent height (approaching 1/2 wavelength) and its higher angle coverage
> for
> short skip contacts. It depends upon how much space and energy you want to
> put into your antenna.
>
> Both vertical and horizontal antennas suffer when they are made short.
> Either one will work quite well when they are only about 1/4 wavelength
> long, but the efficiency drops very quickly once the length goes below 1/4
> wavelength. Furthermore, an "end fed" antenna (such as many verticals),
1/4
> wavelength long or less, suffers from the need for a good low-impedance
r-f
> ground - either an extensive ground system or a good tuned counterpoise.
> Without it, the pattern of the vertical remains the same but the
efficiency
> drops dramatically. That's why the popularity of the GAP and other
> so-called
> "half wave" verticals. And while the manufacturers have done a good job
> designing a "low loss" means of "loading" a physically short antenna to
> look, electrically, like it is longer than it really is. Even so, it is
> still less efficient than a 'full size' antenna. So if someone says that
an
> antenna is a 'full half wave long' on 40 meters, it'd better be 66 feet
end
> to end or it's not a "full half wave long". It might work well. It might
> even work nearly as well as a real half wave antenna (or not), but it
won't
> work as well as a full sized antenna. All "loading" schemes involve some
> losses.
>
> The same applies to shortened horizontal antennas.
>
> Finally, there is an important point you touched upon. You have lots of
> homes around you with aluminum siding, and you have trees. One cardinal
> rule
> is for the antenna to be 'in the clear' for best efficiency and to be able
> to predict the pattern and performance. At the lower frequencies, trees
and
> buildings will have a much smaller effect on the performance. The length
of
> the radio wave is what determines their effect. As the wavelength gets
> longer, the relative 'size' of the trees and buildings gets smaller in
> terms
> of wavelengths, and their effect is reduced. So at the higher frequencies,
> the buildings and trees will reflect and absorb a lot more energy. Also,
if
> there are conductors (like your tree, perhaps) quite close to your
antenna,
> the currents in the antenna can induce currents in the conductor. That
> energy is lost as heat. That effect increases as the frequency is
> decreased.
> ("Lowfer's" operating down on the VLF range avoid trees like the plague,
> from what I read).
>
> Some ops, like Jerry Sevic, W2FMI, who had a open piece of land several
> hundred feet on a side, built a 6-foot tall vertical for 40 meters with an
> extensive grounding system and found its performance virtually identical
to
> a full-size vertical. But that's without significant obstructions close
in.
> And he was comparing it to a full size vertical, not to a horizontal at an
> effective height above ground.
>
> If you've got metal buildings or other obstructions, vertical or
> horizontal,
> you will be better off to get the antenna up and "in the clear".
>
> Ron AC7AC
> K2 # 1289
>
>
>
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