Return-Path: Received: from mtain-md05.r1000.mx.aol.com (mtain-md05.r1000.mx.aol.com [172.29.96.89]) by air-di01.mail.aol.com (v126.13) with ESMTP id MAILINDI011-eab64b4a34ea384; Sun, 10 Jan 2010 15:13:30 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-md05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2771738000073; Sun, 10 Jan 2010 15:13:28 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NU491-00058r-PL for rs_out_1@blacksheep.org; Sun, 10 Jan 2010 20:12:15 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NU490-00058i-Qh for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 20:12:14 +0000 Received: from mtaout01-winn.ispmail.ntl.com ([81.103.221.47]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NU48x-0000pW-DQ for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 20:12:14 +0000 Received: from know-smtpout-1.server.virginmedia.net ([62.254.123.1]) by mtaout01-winn.ispmail.ntl.com (InterMail vM.7.08.04.00 201-2186-134-20080326) with ESMTP id <20100110200702.WAYH17029.mtaout01-winn.ispmail.ntl.com@know-smtpout-1.server.virginmedia.net> for ; Sun, 10 Jan 2010 20:07:02 +0000 Received: from [86.26.81.210] (helo=desktop) by know-smtpout-1.server.virginmedia.net with esmtp (Exim 4.63) (envelope-from ) id 1NU43w-000421-Oj for rsgb_lf_group@blacksheep.org; Sun, 10 Jan 2010 20:07:02 +0000 From: "James Cowburn" To: References: <000e01ca9223$6d16ec90$0517aac0@desktop> <20100110204914.7slzdzt6skoww4so@webmail6.kuleuven.be> <9afca2641001101154y7b99110l20c6ab44435d4213@mail.gmail.com> Date: Sun, 10 Jan 2010 20:06:55 -0000 Message-ID: <003001ca9230$75ecf730$0517aac0@desktop> MIME-Version: 1.0 X-Mailer: Microsoft Office Outlook 11 In-Reply-To: <9afca2641001101154y7b99110l20c6ab44435d4213@mail.gmail.com> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3350 Thread-Index: AcqSLu0/yVhBN7kRQEaDA7KkYgRKnwAAJoSw X-Cloudmark-Analysis: v=1.1 cv=W3tOLUehizD4qj6VhtReFuw5MKb8d+XqjIxlDsIazEA= c=1 sm=0 a=8Qw2kvqKHfsA:10 a=pjcCXyNfAAAA:8 a=F3M5lZpKAAAA:8 a=8RloEfZUAAAA:8 a=fnYqA7hvAAAA:8 a=j6Q1dnSHAAAA:8 a=A06HpNCPAAAA:20 a=zAJiCMBNcDy5foPin4oA:9 a=YCEbx47TukVGdz8QxvMA:7 a=wpwfRCS0WVSyL0cZGGbPMwSisYYA:4 a=8mcaF2JIRJ8A:10 a=wk6s2zzMB60A:10 a=O58u2wXj750A:10 a=gA6IeH5FQcgA:10 a=NWVoK91CQyQA:10 a=c7oDjeM3COfeBqVa:21 a=jaiUaaSr9cAuKbHw:21 a=SSmOFEACAAAA:8 a=6LvAJLjWfmKXamQk7eYA:9 a=wzY1scjfzweyDnmRj2QA:7 a=GU8Zg-rVAc0McpNIfUYcOO0_iswA:4 a=HpAAvcLHHh0Zw7uRqdWCyQ==:117 X-Spam-Score: 0.3 (/) X-Spam-Report: autolearn=disabled,HTML_FONT_BIG=0.256,HTML_MESSAGE=0.001 Subject: RE: LF: Link budget calculation or estimation of dist for given power on WSPR Content-Type: multipart/alternative; boundary="----=_NextPart_000_0031_01CA9230.75ECF730" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.3 required=5.0 tests=HTML_70_80, HTML_FONTCOLOR_UNKNOWN,HTML_FONT_BIG,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: 3039ac1d60594b4a34e85634 X-AOL-IP: 193.82.116.20 ------=_NextPart_000_0031_01CA9230.75ECF730 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Dear All 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. http://www.aubraux.com/design/rf-link-budget-calculator.php Putting in Roger's power of 1mW and a distance of 990km (his best and reception report of -20dB) then it gives for a -20dB signal a "gain factor" for WSPR of 65dB. This seems rather implausibly high so I'm 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 = -28.20 dBW Wavelength = 596.42 m Free Space Loss = 86.39 dB Received Power = -49.59 dBW = 1.10E-5 W = -19.59 dBm = 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 given power on WSPR 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 ------=_NextPart_000_0031_01CA9230.75ECF730 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Dear All

 

I have been inp= utting 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.

 

 

http://www.au= braux.com/design/rf-link-budget-calculator.php

 

Putting in Roge= r’s power of 1mW and a distance of 990km (his best and reception report of -20dB) then it= gives for a -20dB signal a “gain factor” for WSPR of 65dB.

 

This seems rath= er implausibly high so I’m obviously missing a trick somewhere.

 

 

 

 

 

RF= Link Budget Calculator

RF Link Budget Calculator: To calculate power at the re= ceiver input, enter values in the empty boxes below.

 

Transmitte= r Power

W

 

Transmitter Center Frequency

Hz

 

Transmit= Antenna Gain

dB

 

 

 

 

 

Distance= Between Antennas

km

 

 

 

 

 

Receive An= tenna Gain

dB

 

Other Loss= es

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 Cowbu= rn

 

From: owner-rsgb_lf_group@blac= ksheep.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 given power on WSPR

 

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)= 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 <james.cowburn@virgin.net>:=

 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 powe= r setting and antenna configuration?
Clearly, there are differences between separate Rx stations but if &nb= sp;one knows the ratio between two or more Rx stations then it should  b= e 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  capabili= ty 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<blocked::mailto:james.cowburn@virgin.net>







--

http://g3xbm-qrp.blogspot.c= om/
http://www.g3xbm.co.uk
http://www.youtube.com/u= ser/G3XBM
G3XBM    GQRP 1678      ISWL G11088

------=_NextPart_000_0031_01CA9230.75ECF730--