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Date: Sun, 7 Nov 2010 09:10:20 +0000
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From: Roger Lapthorn <rogerlapthorn@gmail.com>
To: rsgb_lf_group@blacksheep.org
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Subject: Re: LF: WSPR T/A hole discussion
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Agreed John.

If about 2mW ERP gets me 1733km on 500kHz WSPR (regularly) then 1W ERP
should be enough to cross the pond. QRP for ever!

73s
Roger G3XBM

On 6 November 2010 23:37, John GM4SLV <gm4slv@sighthound.demon.co.uk> wrote:

> On Sat, 06 Nov 2010 22:25:33 +0100
> "Roelof Bakker" <roelof@ndb.demon.nl> wrote:
>
> > Looking forward to your comments,
>
> Roelof, LF,
>
> Erudite points well put, as ever.
>
> One point keeps nagging at me.
>
> If Jay is correct, and the number of strong (high power/efficient
> antenna/high ERP/groundwave path) W stations is large enough to prevent
> adequate reception of weak signals from Europe, then this also means
> there will be no possibility of weak signal reception from other WD/WE
> stations.
>
> Why are they using such high power on WSPR?
>
> What is the point of this if, as Jay says, everyone will continually be
> being overloaded by their strong groundwave neighbo(u)rs?
>
> Are the high power stations that Jay describes only interested in
> reception reports from Europe, rather than from other W stations? If
> they do want reports from W-land, then by Jay's argument, they will only
> get reports from their near-neighbo(u)rs, as the weaker long distance
> stuff will be blocked due to RX overload.
>
> This can't be right?
>
> I don't believe there is a problem of RX overload preventing reception
> of weak signals (from where-ever), and if there is a problem then the
> solution is to reduce TX power to the point that allows maximum
> transmission distance, and minimum RX overload, rather then segregating
> us into separate parts of the spectrum.
>
> I still don't understand.
>
> John
> GM4SLV
>
>
>


-- 
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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Agreed John. <br><br>If about 2mW ERP gets me 1733km on 500kHz WSPR (regul=
arly) then 1W ERP should be enough to cross the pond. QRP for ever!<br><br=
>73s<br>Roger G3XBM<br><br><div class=3D"gmail_quote">On 6 November 2010=
 23:37, John GM4SLV <span dir=3D"ltr">&lt;<a href=3D"mailto:gm4slv@sightho=
und.demon.co.uk">gm4slv@sighthound.demon.co.uk</a>&gt;</span> wrote:<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;"><div class=3D"i=
m">On Sat, 06 Nov 2010 22:25:33 +0100<br>
&quot;Roelof Bakker&quot; &lt;<a href=3D"mailto:roelof@ndb.demon.nl">roelo=
f@ndb.demon.nl</a>&gt; wrote:<br>
<br>
&gt; Looking forward to your comments,<br>
<br>
</div>Roelof, LF,<br>
<br>
Erudite points well put, as ever.<br>
<br>
One point keeps nagging at me.<br>
<br>
If Jay is correct, and the number of strong (high power/efficient<br>
antenna/high ERP/groundwave path) W stations is large enough to prevent<br=
>
adequate reception of weak signals from Europe, then this also means<br>
there will be no possibility of weak signal reception from other WD/WE<br>
stations.<br>
<br>
Why are they using such high power on WSPR?<br>
<br>
What is the point of this if, as Jay says, everyone will continually be<br=
>
being overloaded by their strong groundwave neighbo(u)rs?<br>
<br>
Are the high power stations that Jay describes only interested in<br>
reception reports from Europe, rather than from other W stations? If<br>
they do want reports from W-land, then by Jay&#39;s argument, they will on=
ly<br>
get reports from their near-neighbo(u)rs, as the weaker long distance<br>
stuff will be blocked due to RX overload.<br>
<br>
This can&#39;t be right?<br>
<br>
I don&#39;t believe there is a problem of RX overload preventing reception=
<br>
of weak signals (from where-ever), and if there is a problem then the<br>
solution is to reduce TX power to the point that allows maximum<br>
transmission distance, and minimum RX overload, rather then segregating<br=
>
us into separate parts of the spectrum.<br>
<br>
I still don&#39;t understand.<br>
<br>
John<br>
<font color=3D"#888888">GM4SLV<br>
<br>
<br>
</font></blockquote></div><br><br clear=3D"all"><br>-- <br><a href=3D"http=
://g3xbm-qrp.blogspot.com/" target=3D"_blank">http://g3xbm-qrp.blogspot.co=
m/</a><br><a href=3D"http://www.g3xbm.co.uk" target=3D"_blank">http://www.=
g3xbm.co.uk</a><br>
<a href=3D"http://www.youtube.com/user/g3xbm" target=3D"_blank">http://www=
.youtube.com/user/g3xbm</a><br>G3XBM=A0=A0 GQRP 1678=A0=A0=A0 ISWL G11088<=
br>

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