Looks like I’m a little late for this party. Thought I’d share my experience
with my very recent vertical project.
The backyard is on a slope. Soil conditions are pathetic, rock and clay (think
it may have been a model for the Flinstones movie set). Numerous trees, about
70 total.
The project was further complicated by the fact I live in antenna restricted
HOA.
I opted for a Mosley RV-7C, which I ordered from the company.
There was ample experimentation with the physical placement to ensure the
antenna would not be readily observable, somewhat away from the surrounding
trees, in a place where I could run radials that did not involve being diverted
around the surrounding trees and as far as possible from my inverted V.
Mosley documentation suggested a single above ground radial for each band. They
provided the length of each but the recommendation did not correspond to any
calculation I could come up with. Nor did they they recommend a height above
ground level for the radials (I’m still a bit disappointed with the doc
provided by the manufacturer).
With all of that said, I did the following:
Antenna is mounted on a 5 ft 4 inch galvanized 2 inch pole buried approximately
3.5 ft in depth. That was as deep as I could get using an auger and a post
hole digger.
There are 4 radials each for 40, 30, 17 and 15 meters. I used the accepted
calculation for quarter wave radials. All radials are run perpendicular to the
base and are not parallel to any other radial.
Each radial is supported by 1/2 inch PVC approximately 12” above ground level.
Yes, I used a fair amount of PVC in order to prevent sagging radials from
touching the ground.
The antenna is fed with about 150ft of Times Microwave LMR-400. I might add, I
did use their connectors.
So far I have no complaints about performance. I am able to use the antenna on
all bands with a tuner. It seems to perform as desired. Don’t think it’s as
omnidirectional as I would like but it does accomplish getting me on the air.
I would like to model the antenna using a reputable antenna analyzer (read what
you like into that statement). But finances dictate that will have to wait.
OK, I’ve sucked up enough band with. Good luck!
W5BXE Richard
>
> Message: 4
> Date: Thu, 9 Apr 2020 02:23:01 +0000
> From: Gary <gary_mayfield@hotmail.com>
> To: "'towertalk@contesting.com'" <towertalk@contesting.com>
> Subject: [TowerTalk] Vertical Antenna Question
> Message-ID:
>
> <CH2PR13MB3671E90C34E152AAA4E54AAC8AC10@CH2PR13MB3671.namprd13.prod.outlook.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> I used my DX Engineering gift certificate to buy a copy of the "Champion
> Radio HF Vertical Performance - Test Methods & Results". I really enjoyed the
> book and learned a lot.
>
> It looks like a vertical is the only antenna I am going to get in my terraced
> back yard. Has anyone done a similar look at verticals where they looked at
> radials vs no radials? There are a lot of claims out there about verticals
> that work without radials. The above test looked at some of those antennas
> but they were mounted over a radial field...
>
> I am still wondering how I am going to run the radials up the brick terraces,
> and they are going to have to be pretty short.
>
> I am ready to listen and learn.
>
> Thanks and 73,
> Gary "Joe" Mayfield, kk0sd
>
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