Rick's message on practicality is sound.
My 80 meter vertical started out as a "Marconi" That is ground rod in the
ground directly under the 7/8" X 63' Cable TV feeder line found in a
recycling yard about 1983 that I dagged up a spruce tree for support (I tied
it to the branches) and used a sheetmetal screw to attach the hot wire to
the shield. It was an immediate improvement for DX over the 80 meter dipole
at 35' (See the 1st Antenna Anthology "Wiring up the Old Spruce.") Since
then I added a few (6) radials on the ground and have always fed it directly
with RG8. Band width - pretty close to all of 75 and 80 meters.
For sure (Well theoretically) if I added more radials the efficiency would
improve, but in the last 25 years that has not been high on the antenna
farming list of chores!
Keep it simple!
Kris KM2KM
----- Original Message -----
From: "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de>
To: "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Sent: Saturday, May 19, 2012 4:48 AM
Subject: Re: [TenTec] Radial Research
> Technical research is useful but sometimes the discussion that follows
> distorts the practical real world realities. Reading these threads
> describing what it takes to obtain perfection, sometimes leads me to
> believe
> that people with less knowledge will be scared off and not try anything.
> That would be a shame.
>
> REALITY: We all should strive to make our antennas as efficient as
> possible
> and Rudi's work is an excellent guide, but even if you can't build
> anything
> remotely close to what he describes, EVERYONE with just a little bit of
> real-estate can build themselves a great vertical antenna with a lot less
> effort than Rudi described.
>
> I would remind you of the THREE reasons for using a vertical antenna in
> the
> first place:
>
> 1. Because you have to; no space for a low band horizontal dipole
> 2. Because you want to improve your ability to work low band DX
> 3. NEW: Your sea container with all of your equipment and antennas got
> lost in transit on its way to some distant island (see T32C DXpedition to
> Christmas Island - www.tt2c.com ), so you organize a bunch of telescoping
> fiberglass poles and some wire and build your vertical antennas on-site.
>
> Let's focus on #2 because this would be the case where we have time and
> space to apply what we've learned from Rudi.
>
> It is fundamental to understand that a good working vertical on the low
> bands is typically 2 to 3 S-Units stronger at a distance DX station than
> your 40' high horizontal dipole. *** This is 12 to 18 dB improvement.***
>
> Considering that, when someone says if I don't get it perfect, I will have
> 2
> to 3 dB pattern distortion and 1 to 2 dB of additional loss. hey, let's
> get
> real. If you live in a city, every antenna you put up has pattern
> distortion, and your signal will never be as good as that of someone
> living
> in the country with lots of space. That's no reason to just give up and
> not
> do anything. Just do the best you can under your own set of
> circumstances:
>
>>> Getting the most out of your own vertical with ground mounted radials is
> pretty easy: just put down as many as you can under consideration of the
> space, time and money you have available. Space them as evenly as you
> can,
> but if you can't, you can't.
>
>>> Getting the most out of your own vertical with elevated radials takes a
> little bit more work but it's not that difficult. The radials must be
> resonant. Measure and string as many as you plan to use, and then with a
> grid dip meter or an antenna analyzer, measure each radial and tune them
> all
> to resonance on the same frequency. This may be a different length for
> each
> radial, considering the surrounding environment. If using the analyzer,
> connect the coax shield to a ground stake. Getting them resonant on the
> same frequency is easy, and will get some of that 2 to 3 dB back.
>
> GRANTED, this is not the perfect solution, but it is the best most of us
> can
> do and you will get a darn good performing vertical out of this; much
> better
> than your low-hanging horizontal dipole.
>
> 73
> Rick, DJ0IP
>
>
>
>
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