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Old August 5th 07, 02:08 PM posted to rec.radio.amateur.antenna
Ian White GM3SEK Ian White GM3SEK is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 232
Default Hammer drills and ground rods, followup



I'd like to drive a ground rod near the point where
the coax hooks to the ladder line from my G5RV,
but it's next to a large oak tree.
I can just imagine what getting through all those
roots would be like.


If you have a rotary-hammer drill (as opposed to a plain hammer) you can
use a very long spiral drill bit to make a pilot hole through all the
roots, before hammering in the ground rod.

SDS masonry bits are available up to 1.0m long and will drill through
almost anything, including tree roots and even solid rock. If you can
drill a pilot hole, it almost guarantees that you'll be able to hammer
in the first 3 feet of ground rod very easily. Beyond that depth, it
depends what kind of ground you're in, and how far your luck holds out.


Highland Ham wrote:
Having followed this thread for some time , my simple question is :

Are ground rods really necessary for a good " RF Earth " ?

Are buried or elevated radials or an area covered with '(galvanised)
wire mesh' not equally effective or even superior ?


Wire mesh makes an excellent RF ground. It is particularly good for
Field Days and DXpeditions because you can quickly roll out a large area
of ground cover (typically in a '+' formation) and then roll it up again
when you're done.

But never for a permanent installation! While clearing the ground at
this new QTH, I ran into an impossible tangle of matted grass and bits
of sharp, rusty mesh that turned out to be an abandoned chicken coop. We
finally had to plane off the whole area with a dozer blade, and that
still didn't get rid of it, of course - all we could do was push the
problem out of the way.

Having experienced the legacy left by abandoned chicken mesh, I have
vowed always to use conventional wire radials that can be pulled out
easily after I'm gone.


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73 from Ian GM3SEK