Selecting a location for the vertical antenna

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Finding a place in the yard for the antenna.


All specifications in mind one of the most important is to minimize interference from my own house and that of my neighbors. The figure below shows the candidate position of the antenna radial pattern with the coax run to the house shown. The run will be about 190 feet for a total of about 220 to the ham shack. The antenna location is also the highest part of the yard although it really is quite flat with no more than about 7 feet difference.

Antenna location in back yard.

What is not shown very well above is the overhead power line moving along the road on the left and an underground street feeding power line that starts from the lower left edge of the property and runs parallel to the street. Electrical noise pickup is a big concern. I have surveyed the site with a receiver several times and, so far, have not detected noise.

It may help the overhead and underground lines are horizontal and the antenna vertical.

What about RF pattern effects?

I wondered that too. About the only thing practical to do to check this is put it into NEC (EzNEC in this case) and run the simulation to see what we get. Here is the very simple setup with a 14MHz vertical and the power line along with a power pole running near by...

EZ-NEC Model with 14MHz vertical antenna and overhead power line nearby.

...with the resulting NEC 3D pattern...

EZ-NEC 3D Pattern with 14MHz vertical antenna and overhead power line nearby.

...and the NEC 3D Pattern from overhead...

Top View of EZ-NEC 3D Pattern with 14MHz vertical antenna and overhead power line nearby.

There is an interaction between the power line and the antenna, but it appears to be small enough to not worry about. Thus we have our location for the antenna.

Here is a view along the coax line to the antenna with a marker in the center of the antenna.

The view of the yard ready to accept a ground system and vertical


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