John,

I once had a magloop for 160 and 80 meters almost as big as the one
you propose. It worked fine. According to predictions. Eventually,
needing the garden space for other projects, I swapped it for a bottle
of New Zealand white wine.

But to reduce the weight of a 1.5-inch diameter copper-pipe conductor
plus the tuning capacitor, the conductor was made of thin-wall, hard
aluminium alloy known as Duralumin in these parts. (Pure aluminium is
far too soft and is useless.)

The loop was formed from three sections of tube which fitted into each
other to make a complete circle. The curvature of the sections had to
be formed in an engineering workshop.

It needed three guy ropes and could be rotated about an angle of 90
degrees, five feet above ground level, inside a 2-inch diameter, cast
iron tube sunk into the soil.

There was an aluminium alloy vertical supporting tube which extended
from below ground level almost to the highest point of the main loop
and the motor-driven tuning capacitor. A vertical conductor, running
diametrically across the main loop, has no effect on electrical
performance.

I had very good neighbours. Never had a single compaint about the
wierd contraption which soared well above the skyline from my side of
the 6-foot high bushes and trees which constituted the boundary
between my property and theirs. It never occurred to me to request
planning permission from the local authorities. With the assistance
of a local Black Country radio friend, G3VFF, a born mechanical
engineer, handicapped by an industrial accident, we just erected it!

It helped, to my satisfaction, to prove the veracity of some of my
radio software programs.

John, I wish you all the very best with your project.
----
Cheers, Reg, G4FGQ.