I have recently mounted the 10 meter loop horizontally at various heights up to 5 meters, first thing I noticed was a substantial reduction in noise. Most of the noise seems to be vertically polarized, so with the loop now being horizontally polarized it doesn't hear the vertical noise so much.
There was not enough activity to compare performance on that occasion but I did find that the higher it was, the better it seemed to work.
Also the bandwidth improved somewhat, whereas when the loop is vertical, it degrades as the loop is raised above ground.
A couple of points about the illustration above.
It's roughly to scale, but could be made larger or smaller,
that just means it's more or less efficient, see the
4nec2 plots to see the difference in radiation patterns.
This one is made from 3 x 3 meter lengths.
The feed loop can be any shape, experimentation is called for here, I've not noticed any real difference between a Plain loop or a Faraday loop to feed the main loop.
If you make the antenna as large as possible the efficiency gained will cover losses incurred by taking a few shortcuts elsewhere.
This antenna is not self supporting, it will need to be mounted on a frame of timber or other non conductive material.
Don't be afraid to experiment or do things a little differently, it all adds to the fun.
VK2YOC
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My latest 40 meter loop is at right,
still in the prototype stage, but shows a lot of promise. This antenna, when configured for 20 meters, covers over 100 kc without tuning, at 2 to 1 SWR.
It is 750mm per side, 4 1/2 meters circumference, 50 mm X 3 mm bar.
More soon.
