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Date: Wed, 26 May 2010 08:55:46 +0100
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From: Roger Lapthorn <rogerlapthorn@gmail.com>
To: rsgb_lf_group@blacksheep.org
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Subject: Re: LF: AW: 8.97kHz - Near field and radiated signals?
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Hi Jacek,

Thanks for this encouraging information. I'll definitely try an e-field TX
antenna later, although space is very limited in my garden.  The grounded
electrode pair "antenna" does appear to be quite effective, but I need to
compare this against a TX e-field antenna and loop antenna.  I've some
questions:

   - What antenna did you use for RX? Loop, e-field probe?
   - Have you tried TXing using grounded electrodes? If so, what range did
   you achieve and what RX antenna did you use?

Thanks again.

73s
Roger G3XBM

On 25 May 2010 22:30, Jacek Lipkowski <sq5bpf@lipkowski.org> wrote:

> On Mon, 24 May 2010, Roger Lapthorn wrote:
>
>   - The best DX targets are quite modest: I would like to exceed 1km
>>
>>  initially with the TX power I currently have (around 4W). If I could
>> reach
>>  G6ALB in the next village 3kms away I would be delighted. If I got any
>>  further I would be both amazed and VERY happy!
>>
>
> Roger - try an e-field antenna. for a few years i have been doing tests
> with loops, and the results were not that good. the best distance was about
> 700m in the city during wintertime with about 40W. i wish i had tried an
> e-field antenna earlier.
>
> the first results with a 40m horizontal wire abt 15m up were far better. i
> got 1.3 km without problems using about 3W in april (so more qrm than in
> winter):
> http://acid.ch.pw.edu.pl/~sq5bpf/ham/vlf/sq5bpf_vlf_test_20100406.jpg<http://acid.ch.pw.edu.pl/%7Esq5bpf/ham/vlf/sq5bpf_vlf_test_20100406.jpg>
>
> the matching was done via a tv transformer, which i see is getting quite
> popular now :)
>
> since you're in a village area you will probably have much less qrm. 3km in
> the winter seems to be a realistic goal.
>
> vy 73
>
> Jacek / SQ5BPF
>
>
>
>


-- 
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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Hi Jacek,<br><br>Thanks for this encouraging information. I&#39;ll definit=
ely try an e-field TX antenna later, although space is very limited in my=
 garden.=A0 The grounded electrode pair &quot;antenna&quot; does appear to=
 be quite effective, but I need to compare this against a TX e-field anten=
na and loop antenna.=A0 I&#39;ve some questions:<br>
<ul><li>What antenna did you use for RX? Loop, e-field probe?</li><li>Have=
 you tried TXing using grounded electrodes? If so, what range did you achi=
eve and what RX antenna did you use? <br></li></ul>Thanks again.<br><br>73=
s<br>
Roger G3XBM<br><br><div class=3D"gmail_quote">On 25 May 2010 22:30, Jacek=
 Lipkowski <span dir=3D"ltr">&lt;<a href=3D"mailto:sq5bpf@lipkowski.org">s=
q5bpf@lipkowski.org</a>&gt;</span> wrote:<br><blockquote class=3D"gmail_qu=
ote" style=3D"margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204,=
 204, 204); padding-left: 1ex;">
On Mon, 24 May 2010, Roger Lapthorn wrote:<br>
<br>
<blockquote class=3D"gmail_quote" style=3D"margin: 0pt 0pt 0pt 0.8ex; bord=
er-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
 =A0- The best DX targets are quite modest: I would like to exceed 1km<div=
 class=3D"im"><br>
 =A0initially with the TX power I currently have (around 4W). If I could=
 reach<br>
 =A0G6ALB in the next village 3kms away I would be delighted. If I got any=
<br>
 =A0further I would be both amazed and VERY happy!<br>
</div></blockquote>
<br>
Roger - try an e-field antenna. for a few years i have been doing tests wi=
th loops, and the results were not that good. the best distance was about=
 700m in the city during wintertime with about 40W. i wish i had tried an=
 e-field antenna earlier.<br>

<br>
the first results with a 40m horizontal wire abt 15m up were far better.=
 i got 1.3 km without problems using about 3W in april (so more qrm than=
 in winter): <a href=3D"http://acid.ch.pw.edu.pl/%7Esq5bpf/ham/vlf/sq5bpf_=
vlf_test_20100406.jpg" target=3D"_blank">http://acid.ch.pw.edu.pl/~sq5bpf/=
ham/vlf/sq5bpf_vlf_test_20100406.jpg</a><br>

<br>
the matching was done via a tv transformer, which i see is getting quite=
 popular now :)<br>
<br>
since you&#39;re in a village area you will probably have much less qrm.=
 3km in the winter seems to be a realistic goal.<br>
<br>
vy 73<br>
<br>
Jacek / SQ5BPF<br>
<br>
<br>
<br>
</blockquote></div><br><br clear=3D"all"><br>-- <br><a href=3D"http://g3xb=
m-qrp.blogspot.com/">http://g3xbm-qrp.blogspot.com/</a><br><a href=3D"http=
://www.g3xbm.co.uk">http://www.g3xbm.co.uk</a><br><a href=3D"http://www.yo=
utube.com/user/g3xbm">http://www.youtube.com/user/g3xbm</a><br>
G3XBM =A0 =A0GQRP 1678 =A0 =A0 =A0ISWL G11088<br>

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