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Date: Fri, 13 Aug 2010 16:08:59 +0100
Message-ID: <AANLkTi=L7RmVBYd7=T36tyxvD1CeUi-3ZOSBeT7i2xmE@mail.gmail.com>
From: Roger Lapthorn <rogerlapthorn@gmail.com>
To: rsgb_lf_group@blacksheep.org
DomainKey-Status: good (testing) 
Subject: LF: A question about loops for 136 and 500kHz TX
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Having considered the antenna options for my small garden, I'm going to
erect a TX loop antenna rather than a Marconi vertical for 136kHz: the
earthing issues are removed and it is easier to build a capacitor selection
box (to tune and match the loop) than wind a huge loading coil and match it.
I've seen some of the webpages dealing with these and understand basically
what is needed (large loop area, thick wire, capacitor match-box, dealing
with high RF currents, etc). I understand the loop will have directionality
and nulls.

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.


Views appreciated, although it may be a case of "suck it and see".

73s
Roger G3XBM

-- 
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
G3XBM   GQRP 1678    ISWL G11088

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Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

Having considered the antenna options for my small garden, I&#39;m going=
 to erect a TX loop antenna rather than a Marconi vertical for 136kHz: the=
 earthing issues are removed and it is easier to build a capacitor selecti=
on box (to tune and match the loop) than wind a huge loading coil and matc=
h it. I&#39;ve seen some of the webpages dealing with these and understand=
 basically what is needed (large loop area, thick wire, capacitor match-bo=
x, dealing with high RF currents, etc). I understand the loop will have di=
rectionality and nulls.<br>
<br>My question is this. <b>Is there any reason why the bottom of the loop=
 cannot be laid along the ground rather than elevated a few metres?</b> Mo=
st 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 loo=
p resistance. <br>
<br>Views appreciated, although it may be a case of &quot;suck it and see&=
quot;.<br><br>73s<br>Roger G3XBM<br clear=3D"all"><br>-- <br><a href=3D"ht=
tp://g3xbm-qrp.blogspot.com/" target=3D"_blank">http://g3xbm-qrp.blogspot.=
com/</a><br>
<a href=3D"http://www.g3xbm.co.uk" target=3D"_blank">http://www.g3xbm.co.u=
k</a><br><a href=3D"http://www.youtube.com/user/g3xbm" target=3D"_blank">h=
ttp://www.youtube.com/user/g3xbm</a><br>G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISW=
L G11088<br>

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