Hi Guys
A very easy to put up, with good results to a distance of 400 miles (at least
from here in MA) , omni directional , is a NIVIS. I studied NIVIS literature
and put up a 1/2 wave dipole on 75 m., only 16 ft above ground, with a ground
radial of 125% of the dipole overall length. The radial is attached to a
ground rod at the mid point of the radial . The radial just lays on the
ground directly below the dipole. I use PolyStealth ™ 14 AWG for the dipole
and the ground radial (PolyStealth wire has a PE(polyethylene) jacket which I
have found the critters do not like to chew on as they
do to much of the PVC I used to use in my woods, thus we came up with PE outer
jacket to combat the critter (rodent) attack . Many swear by it (hams that
is,... the rodents swear at it). HI
Steve, K1PEK DAVIS RF Co. bcc: nh
> ------------------------------
>
> Message: 3
> Date: Sun, 11 Oct 2015 01:36:08 -0700
> From: Jim Brown <jim@audiosystemsgroup.com>
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] Omnidirectional antenna for domestic contests
> Message-ID: <561A1F78.3060104@audiosystemsgroup.com>
> Content-Type: text/plain; charset=windows-1252; format=flowed
>
> On Fri,10/9/2015 12:26 AM, Roger (K8RI) on TT wrote:
>> For me in lower MI about half of the states are between, 200 to 600
>> miles. Extend that to 800 miles and it's nearly 3/4.
>
> Yeah, those flyover states and the hams who live in them don't matter. :)
>> Except for Ca the major # of hams is under 700 miles. Max stateside
>> is the west coast at 2000 miles. That means several antennas for
>> distance to the W and SW
>
> Not necessarily -- a high horizontal antenna with good low angle
> radiation still has plenty of radiation at higher angles. 150-20 degrees
> is a very good angle for stations in the 600-800 mile range, and, by
> inverse square law, a station at 800 miles is 7 dB closer than one at
> 1800 miles.
>
>> Typically F/B is more important than gain,
>
> Huh? For what reason? Especially for contesting and DX, I want maximum
> smoke! I'll reserve F/B for RX antennas.
>
>> but I need short, medium and long distance from SW to W
>
> If you understand how horizontal antennas work and understand inverse
> square law, you need only one for any given direction, as high as most
> hams can hang it. For ANY distance, it's awfully hard to beat a pair of
> high dipoles at right angles to each other, and switch between them.
> "High" means "the best that you can do. :) I can do 140 ft, and I'm
> loud on 80 and 40 at both long and short distances.
>
> Study http://k9yc.com/VertOrHorizontal-Slides.pdf
>
> 73, Jim K9YC
>
>
>
> ------------------------------
>
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