On 13 Aug 2010 at 16:08, Roger Lapthorn wrote:
> My question is this. *Is there any reason why the bottom of the loop
> cannot be laid along the ground rather than elevated a few metres?* Most
> designs show the bottom elevated a bit, but if laid on the soil I could
> use thick coax or multiple wires for part of the loop so reducing the
> loop resistance.
>
I assume you have looked at my pages on 136kHz loops -
http://www.davesergeant.com/loops.htm which are now very dated but
detail the loop I used when I was active on the band. The bottom ran
around my garden fence about one foot from the ground. I suspect laying
it actually on the ground would be bad, but spaced off on fairly
insulated fence - blocks or wood, cannot remember what state the fence
was in at that time, would be OK. There were various theories about
losses from vegetation but how far they relate to loops seems not too
proven - certainly trees made the loop I tried down there pretty lossy.
Cannot say the loop worked that well, but it did allow me some QSOs and
I got the 136kHz award (number 7) for working 5 DXCC. Of course in
those days everybody was on real CW...
73 Dave G3YMC
http://www.davesergeant.com
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