DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws;
  s=s1024; d=btinternet.com;
  h=X-YMail-OSG:Received:X-Mailer:Message-ID:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type;
  b=LrJsTcQJs3QQSQgQ1Q33YEgXuRYofJEOByXUhtZcSLWHlMmhEKOQ4HjwlfThuriH4PT7OLmbxQSoWsrNE1+8pfunrLFRMjy91JRJpVC0wCdIOMEyi3SDUev+sFEISXZ5lWmr71/v1Wwdh+Z8yO/N1XfzaliaM0Y6scN/dkvO6+o=;
Message-ID: <1334162538.37672.YahooMailClassic@web87403.mail.ir2.yahoo.com>
Date: Wed, 11 Apr 2012 17:42:18 +0100 (BST)
From: ALAN MELIA <alan.melia@btinternet.com>
To: rsgb_lf_group@blacksheep.org
In-Reply-To: <4F85ABD4.3080503@iup.uni-heidelberg.de>
MIME-Version: 1.0
DomainKey-Status: good (testing) 
Subject: Re: LF: Earth antennas, Beverages...
Content-Type: multipart/alternative; boundary="1933340020-1596808829-1334162538=:37672"
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
X-AOL-SCOLL-URL_COUNT: 1  
X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d267.1 ; domain : btinternet.com DKIM : pass  
x-aol-sid: 3039ac1d404a4f85b4b851a3
X-AOL-IP: 195.171.43.25
X-AOL-SPF: domain : blacksheep.org SPF : temperror


--1933340020-1596808829-1334162538=:37672
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: quoted-printable

Hi Stefan I have a saying that "any bit of wire will act as an antenna.....=
..but the real question is one of efficiency!"=A0 :-))=A0 There is no doubt=
 a good long one will beat a good short one! (....antennas, I mean .....)

Alan

--- On Wed, 11/4/12, Stefan Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.d=
e> wrote:

From: Stefan Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
Subject: Re: LF: Earth antennas, Beverages...
To: rsgb_lf_group@blacksheep.org
Date: Wednesday, 11 April, 2012, 17:05

=0A=0A=0A=0A  =0A=0AHi Alan,
=0AAm 11.04.2012 17:23, schrieb ALAN MELIA:=0A=0A  =0A    =0A      =0A     =
   Interesting Stefan........though I am not sure it is=0Aactually working =
as a Beverage, They are usually quoted as being=0Abetween a=A0 half and one=
 and a half wavelengths long=0A      =0A    =0A  =0A=0AYes, sri, the word i=
s wrongly used here. I think the name is used since=0Aamateur stations use =
such an antenna on HF too, where it acts as a=0Abeverage. On LF it is to sh=
ort to use that name.
=0A
=0A73, Stefan
=0A
=0A=0A  =0A    =0A      =0A        .....but they are travelling wave antenn=
as. Marconi=0Astations used to lay out an insulated with on the ground abou=
t 5 to 10=0Akm long in the direction of the transmitting station. This had =
no=0A"effective height" at higher frequency interference, whereas the skin=
=0Adepth was significant particularly in "poor" ground at VLF.=A0 My "take"=
=0Ais that they are all coupling loops, coupling to the Earth Ionosphere=0A=
waveguide.....in essence the K9AY works the same way I think.=0ATermination=
 makes them unidirectional. Loads to play with :-))
=0A       =20
=0AAlan
=0A=A0
=0A       =20
=0A--- On Wed, 11/4/12, Stefan Sch=E4fer <Stefan.Schaefer@iup.uni-heidelber=
g.de>=0Awrote:
=0A       =20
=0AFrom: Stefan Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
=0ASubject: LF: Earth antennas, Beverages...
=0ATo: vk2ddi@internode.on.net
=0ACc: "Dimitrios Tsifakis" <dtsifakis@gmail.com>, "Bob"=0A<vk7zl@internode=
.on.net>, "Edgar J Twining"=0A<edgarjtwining@virginbroadband.com.au>,=0Arsg=
b_lf_group@blacksheep.org
=0ADate: Wednesday, 11 April, 2012, 14:12
=0A         =20
=0A          =0A          Hi David,=20
=0A         =20
=0ASorry for my late reply about your beverage antenna mail.
=0A         =20
=0AThanks for your point of view to the beverage antennas and the=0Apicture=
s. That sounds all very interesting and i can imagine about the=0Ahigh sign=
al levels coming from such a antenna. The problem in Germany=0Ais o find a =
place which is far away from man made noise sources and=0Aallow to hung up =
such a long wire.
=0A         =20
=0ABut i have found such a place! :-) However i didn't spend much time and=
=0Ainterest to it regarding receive possibilities. I'm just getting=0Are-in=
spired by thinking of it. It is in a very quiet location!
=0A         =20
=0AIn the forest of Heidelberg in JN49IK77 i hung up a 700m long wire. It=
=0Ais called my earth antenna. The main intention is and was to transmit=0A=
on VLF on this antenna. The far end is grounded by 20 or 30 earth rods,=0A4=
0cm deep and about 1m separated. The same on the other end. This forms=0Aa =
loop where the current flows back through the earth. The lower the=0Afreque=
ncy and the lower the ground conductivity, the deeper the return=0Apath of =
the current, so the bigger the cross section area and the=0Ahigher the effi=
ciency.
=0AThat region is a hill/mountain about 500m ASL and 400m above the local=
=0Aground in some km distance. The ground is out of stone with a layer of=
=0Asoil, about 30cm. The need for a poor ground conductivity stands in=0Aop=
posite to the wanted low loop resistance, which means the need for=0Ahigh e=
ffort on the grounding at each end, i.e. a high number of ground=0Arods. Al=
so the wire length is very important.
=0AAnyway the efficiency will be poor but anyway you have a most seldom=0Aa=
nd interesting transmit antenna whioch is not=0Aresonated, thus it is possi=
ble to transmit on any frequency. I'm also=0Alooking forward to the 500 kHz=
 allocation. It will be nice to use it as=0Aa receive and transmit antenna =
on 475 kHz.
=0AIn summer when it is dry i achieved a loop resistance arround 800 Ohm,=
=0Awhich is coming from the grounding losses dominantly. I've done several=
=0Atransmit tests and achieved 35 dB S/N in 4.5 mHz in a distance of 5 km,=
=0Ato my own VLF grabber.=20
=0ADuring the first times where the antenna was still shorter a wrote a=0As=
hort report with some pictures:=0A          http://dl.dropbox.com/u/1988202=
8/VLF/VLF_5km_with_an_earth_antenna.pdf
=0ATests with Michael Oexner (SWL, NDB hunter) in 49 km were positive too,=
=0Ain DFCW-600, see the attached Mail from 2010. BTW this is a VERY good=0A=
demonstration of the positive effect of band limiting, clipping and=0Anoise=
 blanking of the VLF signals processed in SpecLab. The picture=0Ashown my s=
ignal with and without the SpecLabs noise reduction technics.=0AThis 49km d=
istance in 4.5 mHz=A0 is the current record with an earth=0Aantenna. The tr=
ansmit power was 200...250 watts if i remember correctly.
=0A         =20
=0AI will check if the antenna still exists and will refurbish it. Also i=
=0Awill do new tests there. BTW i've done a recording on VLF using this=0Aa=
ntenna in January, 29th 2011, if someone wants to play with it (1 GB):=0A  =
        http://dl.dropbox.com/u/19882028/VLF/29012011_12UTC_earth%20antenna=
_recording.WAV
=0A         =20
=0AIn VK it seems you can easily arrange such an antenna, maybe even=0Aacro=
ss a stony hill and grounded into the sea at one end. You just need=0Asome =
wire and a portable PA :-) BTW this is the PA i was using:=0A          http=
://www.iup.uni-heidelberg.de/schaefer_vlf/12V_300W_VLF_PA.pdf
=0A         =20
=0A73, Stefan/DK7FC
=0A          =0A          =0A        =0A        =0A      =0A    =0A  =0A=0A=
=0A
--1933340020-1596808829-1334162538=:37672
Content-Type: text/html; charset=iso-8859-1
Content-Transfer-Encoding: quoted-printable

<table cellspacing=3D"0" cellpadding=3D"0" border=3D"0" ><tr><td valign=3D"=
top" style=3D"font: inherit;">Hi Stefan I have a saying that "any bit of wi=
re will act as an antenna.......but the real question is one of efficiency!=
"&nbsp; :-))&nbsp; There is no doubt a good long one will beat a good short=
 one! (....antennas, I mean .....)<br><br>Alan<br><br>--- On <b>Wed, 11/4/1=
2, Stefan Sch=E4fer <i>&lt;Stefan.Schaefer@iup.uni-heidelberg.de&gt;</i></b=
> wrote:<br><blockquote style=3D"border-left: 2px solid rgb(16, 16, 255); m=
argin-left: 5px; padding-left: 5px;"><br>From: Stefan Sch=E4fer &lt;Stefan.=
Schaefer@iup.uni-heidelberg.de&gt;<br>Subject: Re: LF: Earth antennas, Beve=
rages...<br>To: rsgb_lf_group@blacksheep.org<br>Date: Wednesday, 11 April, =
2012, 17:05<br><br><div id=3D"yiv985714206">=0A=0A=0A=0A  =0A<div>=0AHi Ala=
n,<br>=0AAm 11.04.2012 17:23, schrieb ALAN MELIA:=0A<blockquote type=3D"cit=
e">=0A  <table border=3D"0" cellpadding=3D"0" cellspacing=3D"0">=0A    <tbo=
dy>=0A      <tr>=0A        <td style=3D"font: inherit;" valign=3D"top">Inte=
resting Stefan........though I am not sure it is=0Aactually working as a Be=
verage, They are usually quoted as being=0Abetween a&nbsp; half and one and=
 a half wavelengths long</td>=0A      </tr>=0A    </tbody>=0A  </table>=0A<=
/blockquote>=0AYes, sri, the word is wrongly used here. I think the name is=
 used since=0Aamateur stations use such an antenna on HF too, where it acts=
 as a=0Abeverage. On LF it is to short to use that name.<br>=0A<br>=0A73, S=
tefan<br>=0A<br>=0A<blockquote type=3D"cite">=0A  <table border=3D"0" cellp=
adding=3D"0" cellspacing=3D"0">=0A    <tbody>=0A      <tr>=0A        <td st=
yle=3D"font: inherit;" valign=3D"top">.....but they are travelling wave ant=
ennas. Marconi=0Astations used to lay out an insulated with on the ground a=
bout 5 to 10=0Akm long in the direction of the transmitting station. This h=
ad no=0A"effective height" at higher frequency interference, whereas the sk=
in=0Adepth was significant particularly in "poor" ground at VLF.&nbsp; My "=
take"=0Ais that they are all coupling loops, coupling to the Earth Ionosphe=
re=0Awaveguide.....in essence the K9AY works the same way I think.=0ATermin=
ation makes them unidirectional. Loads to play with :-))<br>=0A        <br>=
=0AAlan<br>=0A&nbsp;<br>=0A        <br>=0A--- On <b>Wed, 11/4/12, Stefan Sc=
h=E4fer <i><a rel=3D"nofollow" class=3D"yiv985714206moz-txt-link-rfc2396E" =
ymailto=3D"mailto:Stefan.Schaefer@iup.uni-heidelberg.de" target=3D"_blank" =
href=3D"/mc/compose?to=3DStefan.Schaefer@iup.uni-heidelberg.de">&lt;Stefan.=
Schaefer@iup.uni-heidelberg.de&gt;</a></i></b>=0Awrote:<br>=0A        <bloc=
kquote style=3D"border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; =
padding-left: 5px;"><br>=0AFrom: Stefan Sch=E4fer <a rel=3D"nofollow" class=
=3D"yiv985714206moz-txt-link-rfc2396E" ymailto=3D"mailto:Stefan.Schaefer@iu=
p.uni-heidelberg.de" target=3D"_blank" href=3D"/mc/compose?to=3DStefan.Scha=
efer@iup.uni-heidelberg.de">&lt;Stefan.Schaefer@iup.uni-heidelberg.de&gt;</=
a><br>=0ASubject: LF: Earth antennas, Beverages...<br>=0ATo: <a rel=3D"nofo=
llow" class=3D"yiv985714206moz-txt-link-abbreviated" ymailto=3D"mailto:vk2d=
di@internode.on.net" target=3D"_blank" href=3D"/mc/compose?to=3Dvk2ddi@inte=
rnode.on.net">vk2ddi@internode.on.net</a><br>=0ACc: "Dimitrios Tsifakis" <a=
 rel=3D"nofollow" class=3D"yiv985714206moz-txt-link-rfc2396E" ymailto=3D"ma=
ilto:dtsifakis@gmail.com" target=3D"_blank" href=3D"/mc/compose?to=3Ddtsifa=
kis@gmail.com">&lt;dtsifakis@gmail.com&gt;</a>, "Bob"=0A<a rel=3D"nofollow"=
 class=3D"yiv985714206moz-txt-link-rfc2396E" ymailto=3D"mailto:vk7zl@intern=
ode.on.net" target=3D"_blank" href=3D"/mc/compose?to=3Dvk7zl@internode.on.n=
et">&lt;vk7zl@internode.on.net&gt;</a>, "Edgar J Twining"=0A<a rel=3D"nofol=
low" class=3D"yiv985714206moz-txt-link-rfc2396E" ymailto=3D"mailto:edgarjtw=
ining@virginbroadband.com.au" target=3D"_blank" href=3D"/mc/compose?to=3Ded=
garjtwining@virginbroadband.com.au">&lt;edgarjtwining@virginbroadband.com.a=
u&gt;</a>,=0A<a rel=3D"nofollow" class=3D"yiv985714206moz-txt-link-abbrevia=
ted" ymailto=3D"mailto:rsgb_lf_group@blacksheep.org" target=3D"_blank" href=
=3D"/mc/compose?to=3Drsgb_lf_group@blacksheep.org">rsgb_lf_group@blacksheep=
.org</a><br>=0ADate: Wednesday, 11 April, 2012, 14:12<br>=0A          <br>=
=0A          <div id=3D"yiv985714206">=0A          <div>Hi David, <br>=0A  =
        <br>=0ASorry for my late reply about your beverage antenna mail.<br=
>=0A          <br>=0AThanks for your point of view to the beverage antennas=
 and the=0Apictures. That sounds all very interesting and i can imagine abo=
ut the=0Ahigh signal levels coming from such a antenna. The problem in Germ=
any=0Ais o find a place which is far away from man made noise sources and=
=0Aallow to hung up such a long wire.<br>=0A          <br>=0ABut i have fou=
nd such a place! :-) However i didn't spend much time and=0Ainterest to it =
regarding receive possibilities. I'm just getting=0Are-inspired by thinking=
 of it. It is in a very quiet location!<br>=0A          <br>=0AIn the fores=
t of Heidelberg in JN49IK77 i hung up a 700m long wire. It=0Ais called my e=
arth antenna. The main intention is and was to transmit=0Aon VLF on this an=
tenna. The far end is grounded by 20 or 30 earth rods,=0A40cm deep and abou=
t 1m separated. The same on the other end. This forms=0Aa loop where the cu=
rrent flows back through the earth. The lower the=0Afrequency and the lower=
 the ground conductivity, the deeper the return=0Apath of the current, so t=
he bigger the cross section area and the=0Ahigher the efficiency.<br>=0ATha=
t region is a hill/mountain about 500m ASL and 400m above the local=0Agroun=
d in some km distance. The ground is out of stone with a layer of=0Asoil, a=
bout 30cm. The need for a poor ground conductivity stands in=0Aopposite to =
the wanted low loop resistance, which means the need for=0Ahigh effort on t=
he grounding at each end, i.e. a high number of ground=0Arods. Also the wir=
e length is very important.<br>=0AAnyway the efficiency will be poor but an=
yway you have a most seldom=0Aand interesting transmit antenna whioch is <u=
><b>not</b></u>=0Aresonated, thus it is possible to transmit on any frequen=
cy. I'm also=0Alooking forward to the 500 kHz allocation. It will be nice t=
o use it as=0Aa receive and transmit antenna on 475 kHz.<br>=0AIn summer wh=
en it is dry i achieved a loop resistance arround 800 Ohm,=0Awhich is comin=
g from the grounding losses dominantly. I've done several=0Atransmit tests =
and achieved 35 dB S/N in 4.5 mHz in a distance of 5 km,=0Ato my own VLF gr=
abber. <br>=0ADuring the first times where the antenna was still shorter a =
wrote a=0Ashort report with some pictures:=0A          <a rel=3D"nofollow" =
class=3D"yiv985714206moz-txt-link-freetext" target=3D"_blank" href=3D"http:=
//dl.dropbox.com/u/19882028/VLF/VLF_5km_with_an_earth_antenna.pdf">http://d=
l.dropbox.com/u/19882028/VLF/VLF_5km_with_an_earth_antenna.pdf</a><br>=0ATe=
sts with Michael Oexner (SWL, NDB hunter) in 49 km were positive too,=0Ain =
DFCW-600, see the attached Mail from 2010. BTW this is a VERY good=0Ademons=
tration of the positive effect of band limiting, clipping and=0Anoise blank=
ing of the VLF signals processed in SpecLab. The picture=0Ashown my signal =
with and without the SpecLabs noise reduction technics.=0AThis 49km distanc=
e in 4.5 mHz&nbsp; is the current record with an earth=0Aantenna. The trans=
mit power was 200...250 watts if i remember correctly.<br>=0A          <br>=
=0AI will check if the antenna still exists and will refurbish it. Also i=
=0Awill do new tests there. BTW i've done a recording on VLF using this=0Aa=
ntenna in January, 29th 2011, if someone wants to play with it (1 GB):=0A  =
        <a rel=3D"nofollow" class=3D"yiv985714206moz-txt-link-freetext" tar=
get=3D"_blank" href=3D"http://dl.dropbox.com/u/19882028/VLF/29012011_12UTC_=
earth%20antenna_recording.WAV">http://dl.dropbox.com/u/19882028/VLF/2901201=
1_12UTC_earth%20antenna_recording.WAV</a><br>=0A          <br>=0AIn VK it s=
eems you can easily arrange such an antenna, maybe even=0Aacross a stony hi=
ll and grounded into the sea at one end. You just need=0Asome wire and a po=
rtable PA :-) BTW this is the PA i was using:=0A          <a rel=3D"nofollo=
w" class=3D"yiv985714206moz-txt-link-freetext" target=3D"_blank" href=3D"ht=
tp://www.iup.uni-heidelberg.de/schaefer_vlf/12V_300W_VLF_PA.pdf">http://www=
.iup.uni-heidelberg.de/schaefer_vlf/12V_300W_VLF_PA.pdf</a><br>=0A         =
 <br>=0A73, Stefan/DK7FC<br>=0A          </div>=0A          </div>=0A      =
  </blockquote>=0A        </td>=0A      </tr>=0A    </tbody>=0A  </table>=
=0A</blockquote>=0A</div>=0A</div></blockquote></td></tr></table>
--1933340020-1596808829-1334162538=:37672--