Return-Path: Received: from rly-db07.mx.aol.com (rly-db07.mail.aol.com [172.19.130.82]) by air-db08.mail.aol.com (v125.7) with ESMTP id MAILINDB083-ad34aba922c94; Wed, 23 Sep 2009 17:25:27 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-db07.mx.aol.com (v125.7) with ESMTP id MAILRELAYINDB071-ad34aba922c94; Wed, 23 Sep 2009 17:25:01 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MqZJz-0001cq-Vo for rs_out_1@blacksheep.org; Wed, 23 Sep 2009 22:24:19 +0100 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MqZJz-0001ch-D5 for rsgb_lf_group@blacksheep.org; Wed, 23 Sep 2009 22:24:19 +0100 Received: from smtp5.freeserve.com ([193.252.22.151] helo=smtp6.freeserve.com) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1MqZJo-0000SD-V1 for rsgb_lf_group@blacksheep.org; Wed, 23 Sep 2009 22:24:11 +0100 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3524.me.freeserve.com (SMTP Server) with ESMTP id 79C2A1C00085 for ; Wed, 23 Sep 2009 23:24:03 +0200 (CEST) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3524.me.freeserve.com (SMTP Server) with ESMTP id 64AB81C00087 for ; Wed, 23 Sep 2009 23:24:03 +0200 (CEST) Received: from AGB (unknown [91.109.15.62]) by mwinf3524.me.freeserve.com (SMTP Server) with SMTP id 6F9981C00085 for ; Wed, 23 Sep 2009 23:24:00 +0200 (CEST) X-ME-UUID: 20090923212400457.6F9981C00085@mwinf3524.me.freeserve.com Message-ID: <053D0B59431F4F798458F8429FDCBA9B@AGB> From: "Graham" To: References: In-Reply-To: Date: Wed, 23 Sep 2009 22:23:58 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8064.206 X-MIMEOLE: Produced By Microsoft MimeOLE V14.0.8064.206 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: s/n shown by wspr .... what is it actually showing ? Content-Type: multipart/alternative; boundary="----=_NextPart_000_002E_01CA3C9C.8BB5C270" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_40_50,HTML_MESSAGE, MISSING_OUTLOOK_NAME 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-IP: 193.82.116.20 ------=_NextPart_000_002E_01CA3C9C.8BB5C270 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Right .. thanks Andy ... that makes sense ... looking at rms power= in a bandwidth and not the spot noise power at one frequency (+/- spe= c bw) ? why the 100 hz , as the wspr window is 200 hz wide , is the softwa= re looking +/- 50 from the decode frequency ? To make use of the level in terms of the path suitability for say= a data transmission ... is there a quick way of working backwards ,= if you know the minimum s/n that the mode will handle, using the reported= wspr result ?=20 Tnx- G .. =20 From: Andy Talbot=20 Sent: Wednesday, September 23, 2009 9:50 PM To: rsgb_lf_group@blacksheep.org=20 Subject: Re: LF: s/n shown by wspr .... what is it actually showing ? Its normalised to 2500Hz banbdwidth - approximately an SSB filter's wo= rth. So +20dB in 100Hz =3D -3dB in 2500Hz. =20 Andy www.g4jnt.com =20 On 23/09/2009, Graham wrote:=20 Just watched Dave's G3YXM wspr signal on spec-lab ,=20 Spec-lab showed the signal to be a constant 20 dB over the back= ground noise floor of the rx=20 so in my book that's 20 dB s/n =20 The wspr decode is showing -3 dB s/n ? What is it actually displaying ? G ..=20 --=20 Andy www.g4jnt.com this email has been scanned for political correctness by the nanny sta= te=20 ----------------------------------------------------------------------= ---------- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.409 / Virus Database: 270.13.112/2391 - Release Date: 09/= 23/09 18:00:00 ------=_NextPart_000_002E_01CA3C9C.8BB5C270 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Right  .. thanks Andy ... that= makes sense=20 ...  looking at  rms power in a bandwidth and not the spot= noise power=20 at one frequency (+/- spec bw) ?
 
why the  100 hz , as the = wspr =20 window is 200 hz wide , is the  software looking +/-  50&nbs= p; from=20 the  decode frequency ?
 
To make use of the  level in ter= ms of=20 the  path suitability  for say a data transmission ... is th= ere a=20 quick way  of working backwards , if you
know the  minimum s/n that the&n= bsp; mode will=20 handle, using the  reported wspr  result ?
 
Tnx- G ..  

Sent: Wednesday, September 23, 2009 9:50 PM
Subject: Re: LF: s/n shown by wspr .... what is it actuall= y showing=20 ?

Its normalised to 2500Hz banbdwidth - approximately an SSB filter= 's=20 worth.
 
So +20dB in 100Hz   =3D   -3dB in 2500Hz.&nbs= p; =20
 
Andy


 
On 23/09/2009, Graham=20 <g8fzk@g8fzk.fsnet.co.uk= >=20 wrote:=20
Just watched Dave's G3YXM  wsp= r  signal=20 on spec-lab ,
 
Spec-lab showed the  signal to=   be a=20 constant  20 dB over the back ground noise floor  of the&n= bsp; rx=20
so in my  book that's 20 dB&nb= sp;=20 s/n  
 
The  wspr  decode is = ; showing -3=20 dB s/n ?
 
What is it  actually  dis= playing=20 ?
 
G ..
 
 
 



--
Andy
www.g4jnt.com

this email has been scanned=20 for political correctness by the nanny state=20



No virus found in this incoming message.
Checked by AVG= -=20 www.avg.com
Version: 8.5.409 / Virus Database: 270.13.112/2391 -= Release=20 Date: 09/23/09 18:00:00
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