Return-Path: Received: from mtain-dc03.r1000.mx.aol.com (mtain-dc03.r1000.mx.aol.com [172.29.64.131]) by air-di06.mail.aol.com (v126.13) with ESMTP id MAILINDI061-eaca4b4a3e71155; Sun, 10 Jan 2010 15:54:09 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dc03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2CC3E38000250; Sun, 10 Jan 2010 15:54:08 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NU4mQ-0005IE-7X for rs_out_1@blacksheep.org; Sun, 10 Jan 2010 20:52:58 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NU4mP-0005I5-4r for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 20:52:57 +0000 Received: from fg-out-1718.google.com ([72.14.220.153]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NU4mL-00010M-Hg for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 20:52:57 +0000 Received: by fg-out-1718.google.com with SMTP id e12so353981fga.10 for ; Sun, 10 Jan 2010 12:52:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=F+KPA0LJsNGDFJBc0wRl/qusNqjz6YMklAIg2akho70=; b=IbvWIbQxEjRPJhumjMHlwdIyN7l3zDnClsxFfZwHspDX+8fezcp3Q2NcPBmaFNq0Ib hcWeVuKH5Et0B4xBOycFxGLcqe/+KPMhobdVjaqba2UBRF0IMtonksWDYUtPjWb88f6U kTTfdsgI4h5Uf6LConh18nVvn39osrfAq/pVI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=JGmMLZRBhdYY5d/lCVvax4pIwkhtwEewLHMWyv9x7sy8eYhGv0NWbD4JyfQy4SITyn jC+QPgz9LrvjE7JcJUF84stek/gKNw2AfFiqyGKRdkTqZiEyLbmSA97Vpgx6gUttWQ3Z q0Qw4OQbKcAI6nFXG8D4C4ByuHx/K0KMTnyx8= MIME-Version: 1.0 Received: by 10.239.166.141 with SMTP id b13mr140371hbe.101.1263156769622; Sun, 10 Jan 2010 12:52:49 -0800 (PST) In-Reply-To: <003001ca9230$75ecf730$0517aac0@desktop> References: <000e01ca9223$6d16ec90$0517aac0@desktop> <20100110204914.7slzdzt6skoww4so@webmail6.kuleuven.be> <9afca2641001101154y7b99110l20c6ab44435d4213@mail.gmail.com> <003001ca9230$75ecf730$0517aac0@desktop> Date: Sun, 10 Jan 2010 20:52:49 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.4 (/) X-Spam-Report: autolearn=disabled,HTML_FONT_BIG=0.256,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126 Subject: Re: LF: Link budget calculation or estimation of dist for given power on WSPR Content-Type: multipart/alternative; boundary=001485f1e7748c8e3c047cd59aba 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_70_80,HTML_EVENT_UNSAFE, HTML_FONTCOLOR_UNKNOWN,HTML_FONT_BIG,HTML_MESSAGE, HTML_TAG_EXISTS_TBODY 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: 3039ac1d40834b4a3e707922 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --001485f1e7748c8e3c047cd59aba Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable That spreadsheet is for calculating the free space path loss between two stations - given by L =3D 32.4 + 20.LOG(F.d) F in MHz, d in km Totally inappropriate for LF ionospheric, groundwave , microwave ducting and even tropospheric propagation. In fact, only really applicable to satellites and hilltop to hilltop links Andy www.g4jnt.com This email has been scanned for damaging side-effects by the health and safety police, is guaranteed to contain no substances hazardous to health, but may contribute to dissolving the nether and polar regions 2010/1/10 James Cowburn > Dear All > > > > I have been inputting some numbers into the calculator from the link bel= ow, > clearly some assumptions need to be made as well as guesstimates but thi= s > may be able to give an idea of the range expected at a given power, and > assuming x hops etc. > > > > > > http://www.aubraux.com/design/rf-link-budget-calculator.php > > > > Putting in Roger=92s power of 1mW and a distance of 990km (his best and > reception report of -20dB) then it gives for a -20dB signal a =93gain fa= ctor=94 > for WSPR of 65dB. > > > > This seems rather implausibly high so I=92m obviously missing a trick > somewhere. > > > > > > > > > > > *RF Link Budget Calculator* > > *RF Link Budget Calculator*: To calculate power at the receiver input, > enter values in the empty boxes below. > > > > Transmitter Power > > W > > > > Transmitter Center Frequency > > Hz > > > > Transmit Antenna Gain > > dB > > > > > > > > > > > > Distance Between Antennas > > km > > > > > > > > > > > > Receive Antenna Gain > > dB > > > > Other Losses > > dB > > > > > *Results* > > > > EIRP > > =3D > > -28.20 > > dBW > > Wavelength > > =3D > > 596.42 > > m > > Free Space Loss > > =3D > > 86.39 > > dB > > > > > > > > > > Received Power > > =3D > > -49.59 > > dBW > > > > =3D > > 1.10E-5 > > W > > > > =3D > > -19.59 > > dBm > > > > =3D > > 1.10E-2 > > mW > > > > > > With best regards > > > > > > *Jim* > > > > > > Dr. James Cowburn > > > > *From:* owner-rsgb_lf_group@blacksheep.org [mailto: > owner-rsgb_lf_group@blacksheep.org] *On Behalf Of *Roger Lapthorn > *Sent:* 10 January 2010 19:55 > > *To:* rsgb_lf_group@blacksheep.org > *Subject:* Re: LF: Link budget calculation or estimation of dist for giv= en > power on WSPR > > > > Do we know how many dB loss (over land and over sea) for a single hop Ri= k? > > 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 curren= t > 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 setti= ng > 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 possi= ble > to pro-rate or estimate at least the signal strength at a given Rx base= d 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 ha= s > the same capability as GM4SLV and if their capability is different, the= n 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 fo= r 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 > --001485f1e7748c8e3c047cd59aba Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
That spreadsheet is for calculating the free space path loss between= two stations - given by L =3D 32.4 + 20.LOG(F.d)=A0=A0 F in MHz, d in km<= /div>
=A0
Totally inappropriate for LF ionospheric, =A0groundwave , microwave= ducting and even =A0tropospheric propagation.
=A0
In fact, only really applicable to satellites and hilltop to hilltop= links

Andy
www.g4jnt.= com

This email has been scanned for damaging side-effects by th= e health and safety police, is guaranteed to contain no substances hazardo= us to health, but may contribute to dissolving the nether and polar region= s


2010/1/10 James Cowburn <<= a href=3D"mailto:james.cowburn@virgin.net">james.cowburn@virgin.net>= ;

Dear All

=A0

I have been= inputting some numbers into the calculator from the link below, clearly= some assumptions need to be made as well as guesstimates but this may be= able to give an idea of the range expected at a given power, and assuming= x hops etc.

=A0

=A0

http://www.aubraux.com/design/rf-link-budget-calculator.php<= /font>

=A0

Putting in Ro= ger=92s power of 1mW and a distance of 990km (his best and reception repor= t of -20dB) then it gives for a -20dB signal a =93gain factor=94 for WSPR= of 65dB.

=A0

This seems ra= ther implausibly high so I=92m obviously missing a trick somewhere.=

=A0

=A0

=A0

=A0

=A0

RF= Link Budget Calculator

RF Link Budget Calculator: To calculat= e power at the receiver input, enter values in the empty boxes below.

=A0

=A0

R= esults

=A0

Transmitter= Power

W

=A0

Transmitter= Center Frequency

Hz

=A0

Transmit An= tenna Gain

dB

=A0

=A0

=A0

=A0

=A0

Distance Be= tween Antennas

km

=A0

=A0

=A0

=A0

=A0

Receive Ant= enna Gain

dB

=A0

Other Losse= s

dB

=A0

=A0

=A0

With best reg= ards=

=A0

=A0

Jim

=A0

=A0

Dr. James Cow= burn

=A0

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsg= b_lf_group@blacksheep.org] On Beh= alf Of Roger Lapthorn
Sent: 10 January 2010 19:5= 5=20


To:= rsgb_lf= _group@blacksheep.org
Subject:= Re: LF: Link budget calculation or estimation of dist for given power on= WSPR

=A0

Do we know how many= dB loss (over land and over sea) for a single hop Rik?

73s
Roge= r G3XBM

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

Jim,

if ionoshperic propagation is involved= signal strength (and thus SNR) depends more of the number of hops involve= d 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 dis= tance?
As it seems I can get up to GM4SLV reasonably consistently on my= =A0current antenna/power setting with a SNR of around -22dB and the =A0li= mit for WSPR is around -30dB then is there a means for roughly =A0estimati= ng or indeed accurately calculating the Expected Max Range =A0(EMR) at tha= t power setting 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 Co= wburn G7NKS

E james.cowburn@virgin.net<= ;blocked::mailto:james.cowburn@virgin.net>







--

http://g3xbm-qrp.blogspot.c= om/
http://ww= w.g3xbm.co.uk
http://www= .youtube.com/user/G3XBM
G3XBM =A0 =A0GQRP 1678 =A0 =A0 =A0ISWL G110= 88


--001485f1e7748c8e3c047cd59aba--

EIRP

=3D

-28.20

dBW

Wavelength

=3D

596.42

m

Free Space Loss

=3D

86.39

dB

=A0

=A0

=A0

=A0

Received Power

=3D

-49.59

dBW

=A0

=3D

1.10E-5

W

=A0

=3D

-19.59

dBm

=A0

=3D

1.10E-2

mW