Hi Scott,
Yes. The more rocks the better the result. The lower the ground
conductance, the deeper the flow back current and thus the larger the
loop area. Near my hill/mountain (is 520 m ASL a hill or a mointain if
the sourrounding region is about 120 m ASL?) there is a stone pit
(http://maps.google.de/maps?ll=49.456911,8.681259&spn=0,0.027423&t=h&z=15&lci=com.panoramio.all&layer=c&cbll=49.456911,8.681259&cbp=12,0,,0,5&photoid=po-23608032).
I cannot hit a earth rod more than 0.4 m into the soil since there is
the stone!
This makes more effort on the earth rod site but all in all the stone is
a big advantage is think!
BTW, you do not need a big wire! The losses are dominated by your ground
resistance, not by the wire resistance. So you can use 1 mm diameter or
less. This makes it easy and cheap. Telephone drop wire is a very good
choice. The longer the wire the better! Voltages are moderate and
currents as well, depending of power and ground losses of course :-)
I will keep you informed about my progress on improving this antenna (soon).
73, Stefan/DK7FC
Am 28.09.2010 02:47, schrieb Scott Tilley:
Hi Stefan and Group
The topic of Earth antennas is interesting. My question is how well
will one work over rock? I really have little or no soil here. Any
experience with this situation?
I do have a 100m deep well into the rock down to an aquifer. Perhaps
that for one end and the other???
Any experience in this area out there?
TU Scott
Scott, don't you want to give VLF a chance? If you have so much space
(like i have too in the Heidelberg's forest, but not as close to my
home QTH), you could try to build a (earth) loop of some 10000 m^2
and could start a canadian VLF experiment!? I would watch out for
your signal! :-)
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