On Thu, 19 Apr 2007 17:55:03 +0100, "Richard"
wrote:

I want to put up a "long wire" with the feedpoint at one of the back end
corners of the garden. I need a good RF ground.

If I got a length of 6 foot wide copper sheet and made out of it a cylinder,
say 6 feet in diameter, and then placed that cylinder in an upwards position
in the ground, the top level with the surface, would that be a good idea for
trying to acheive a decent RF ground? Also, is there anything I could place
around the cylinder to better the conduction between the cyinder and the
earth around it? Should I drill holes in the cylinder so I can pour water
into the cylinder to keep the ground around it moist?

Would I still benefit from some radials in the ground?

My garden's about 33 foot long, 21 foot wide. Ground gets rather rocky and a
bit sandyish at about 9 inches or so from the surface.TIA.

Check out http://www.bencher.com/pdfs/00361ZZV.pdf
and http://www.bencher.com/pdfs/00803ZZV.pdf

We usually associate an RF ground with verticals. I believe what you
are referring to as a "long wire" is usually called an :inverted L".

I think your proposed depth of 1 foot or more may be too deep for best
performance.

If you are planning cultivate your garden on a regular basis and use
it for a radial field you have some unique problems. Insulated wire on
top of the ground works as well as buried bare wire.

The consensus seems to be that each time you double your number of
radials you gain a db up to about 128 of them. essentially, more is
better. Popular thinking is that 16 are the minimum.

I experimented with using electrical extension cords of various length
for a radial system and found that all efforts would work but more is
always better! One radial will get you on the air but just barely! I
suspect a quarter wave radiator in any configuration and 4 radials
would beat any mobile installation.

If I were you I would invest in a few orange extension cords and run
them on top of the ground IN the garden rows. Orange will be easy to
see and avoid when you cultivate your garden. They will be easy to
remove and re deploy for garden cleanup.
Plan on assuring the curious neighbors that you are electrically
stimulating your garden. That will probably subdue any objections.

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"