Return-Path: Received: from mtain-mc07.r1000.mx.aol.com (mtain-mc07.r1000.mx.aol.com [172.29.96.79]) by air-de02.mail.aol.com (v126.13) with ESMTP id MAILINDE023-5ea84b4a30d3de; Sun, 10 Jan 2010 14:56:03 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mc07.r1000.mx.aol.com (Internet Inbound) with ESMTP id E43ED38000209; Sun, 10 Jan 2010 14:56:01 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NU3sQ-0004gQ-Ow for rs_out_1@blacksheep.org; Sun, 10 Jan 2010 19:55:06 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NU3sQ-0004gB-2m for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 19:55:06 +0000 Received: from mail-bw0-f221.google.com ([209.85.218.221]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NU3sM-0004GA-P6 for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 19:55:05 +0000 Received: by bwz21 with SMTP id 21so13501925bwz.4 for ; Sun, 10 Jan 2010 11:54:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=5Yh1OG48GaXvdVtq5qDgtUuHrfUMp4G08/5TAI3ofnI=; b=Q3g0LI7YN3tGqEV5IoHkgIBEM+anYnICGtifaN8xJQpYFyu9OsBGglEg5ZtCETPJXN vLKznhRyUnOlXUzt3en+0YBzHRQ/MUs0E+P4bWbfc9651DSmJfoqFCUl66jTV1RIwkWd 9A+h4OcNSK0Hjp5ZXuMLfT2X8i4BciOPvOQMo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=tiuieuIOs8uigB7eETB8vAALDVoNGyhKI4kuPjrIHdNVprw/Q8qlR8yjzBx6VuUpFm TqXH5Uy6a67ILeM9ZXEAoiKYDHlQy4ZRgCs3RFKoiZaF3H30ahRi0jL5F5UesCRFjIvt qLOTPMrzrQ1F6z115dGe3wV9TmA3XfW4w4wMM= MIME-Version: 1.0 Received: by 10.204.20.210 with SMTP id g18mr2992554bkb.121.1263153296382; Sun, 10 Jan 2010 11:54:56 -0800 (PST) In-Reply-To: <20100110204914.7slzdzt6skoww4so@webmail6.kuleuven.be> References: <000e01ca9223$6d16ec90$0517aac0@desktop> <20100110204914.7slzdzt6skoww4so@webmail6.kuleuven.be> Date: Sun, 10 Jan 2010 19:54:56 +0000 Message-ID: <9afca2641001101154y7b99110l20c6ab44435d4213@mail.gmail.com> From: Roger Lapthorn To: rsgb_lf_group@blacksheep.org X-Karma: unknown: DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: Link budget calculation or estimation of dist for given power on WSPR Content-Type: multipart/alternative; boundary=000325558ea687210d047cd4cb8b X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_20_30,HTML_MESSAGE autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false x-aol-global-disposition: G x-aol-sid: 3039ac1d604f4b4a30d12545 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --000325558ea687210d047cd4cb8b Content-Type: text/plain; charset=ISO-8859-1 Do we know how many dB loss (over land and over sea) for a single hop Rik? 73s Roger G3XBM 2010/1/10 Rik Strobbe > Jim, > > if ionoshperic propagation is involved signal strength (and thus SNR) > depends more of the number of hops involved than the absolute distance. > And each hop "costs" a number of dB's in signal strength. > > 73, Rik ON7YD - OR7T > > > Quoting James Cowburn : > > Dear LF, >> Has anyone any ideas or suggestions on a resource for calculation of a >> link budget for WSPR over a set distance? >> As it seems I can get up to GM4SLV reasonably consistently on my current >> antenna/power setting with a SNR of around -22dB and the limit for WSPR is >> around -30dB then is there a means for roughly estimating or indeed >> accurately calculating the Expected Max Range (EMR) at that power setting >> and antenna configuration? >> Clearly, there are differences between separate Rx stations but if one >> knows the ratio between two or more Rx stations then it should be possible >> to pro-rate or estimate at least the signal strength at a given Rx based on >> its performance with other known signals. >> If I can do 916km with an SNR of say -22dB then how much further would >> the remaining 8dB or so of WSPR detection get me, assuming the other Rx >> has the same capability as GM4SLV and if their capability is different, >> then is it fine to factor for the dB difference over known paths/signals? >> Thanks in advance for any answers or pointers and best wishes to all for >> a great 2010 >> With best regards >> >> >> Jim >> >> >> Dr. James Cowburn G7NKS >> E james.cowburn@virgin.net >> >> >> >> > > > -- http://g3xbm-qrp.blogspot.com/ http://www.g3xbm.co.uk http://www.youtube.com/user/G3XBM G3XBM GQRP 1678 ISWL G11088 --000325558ea687210d047cd4cb8b Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Do we know how many dB loss (over land and over sea) for a single hop Rik?=

73s
Roger G3XBM

2010/1/10 Rik= Strobbe <Rik.Strobbe@fys.kuleuven.be>
Jim,

if ionoshperic propagation is involved signal strength (and thus SNR) depe= nds more of the number of hops involved than the absolute distance.
And each hop "costs" a number of dB's in signal strength.
73, Rik =A0ON7YD - OR7T


Quoting James Cowburn <james.cowburn@virgin.net>:

=A0Dear LF,
Has anyone any ideas or suggestions on a resource for calculation of =A0a= link budget for WSPR over a set distance?
As it seems I can get up to GM4SLV reasonably consistently on my =A0curren= t antenna/power setting with a SNR of around -22dB and the =A0limit for WS= PR is around -30dB then is there a means for roughly =A0estimating or inde= ed accurately calculating the Expected Max Range =A0(EMR) at that power se= tting and antenna configuration?
Clearly, there are differences between separate Rx stations but if =A0one= knows the ratio between two or more Rx stations then it should =A0be poss= ible to pro-rate or estimate at least the signal strength at =A0a given Rx= based on its performance with other known signals.
If I can do 916km with an SNR of say -22dB then how much further =A0would= the remaining =A08dB or so of WSPR detection get me, assuming =A0the othe= r Rx has the same capability as GM4SLV and if their =A0capability is diffe= rent, then is it fine to factor for the dB =A0difference over known paths/= signals?
Thanks in advance for any answers or pointers and best wishes to all =A0fo= r a great 2010
With best regards


Jim


Dr. James Cowburn G7NKS
E james.cowb= urn@virgin.net<blocked::mailto:james.cowburn@virgin.net>









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G3XBM =A0 =A0GQRP 1678 =A0 =A0 =A0ISWL G11088
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