Return-Path: Received: from mtain-dd08.r1000.mx.aol.com (mtain-dd08.r1000.mx.aol.com [172.29.64.148]) by air-ma02.mail.aol.com (v129.4) with ESMTP id MAILINMA021-b4f34cd6a95f20; Sun, 07 Nov 2010 08:27:59 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dd08.r1000.mx.aol.com (Internet Inbound) with ESMTP id 27649380000D5; Sun, 7 Nov 2010 08:27:57 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PF5GS-0004q6-54 for rs_out_1@blacksheep.org; Sun, 07 Nov 2010 13:26:32 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PF5GR-0004px-Gu for rsgb_lf_group@blacksheep.org; Sun, 07 Nov 2010 13:26:31 +0000 Received: from smtp6.freeserve.com ([193.252.22.192]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PF5GP-0004bY-KO for rsgb_lf_group@blacksheep.org; Sun, 07 Nov 2010 13:26:31 +0000 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3626.me.freeserve.com (SMTP Server) with ESMTP id 434DA7000089 for ; Sun, 7 Nov 2010 14:26:24 +0100 (CET) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3626.me.freeserve.com (SMTP Server) with ESMTP id 36AC2700008B for ; Sun, 7 Nov 2010 14:26:24 +0100 (CET) Received: from AGB (unknown [91.109.47.43]) by mwinf3626.me.freeserve.com (SMTP Server) with SMTP id B74B57000089 for ; Sun, 7 Nov 2010 14:26:23 +0100 (CET) X-ME-UUID: 20101107132623750.B74B57000089@mwinf3626.me.freeserve.com Message-ID: From: "Graham" To: References: In-Reply-To: Date: Sun, 7 Nov 2010 13:26:23 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 X-Antivirus: avast! (VPS 101107-0, 07/11/2010), Outbound message X-Antivirus-Status: Clean X-Spam-Score: 0.3 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,MAILTO_TO_SPAM_ADDR=0.276 Subject: Re: Wideband Noise on 500 kHz [was RE: LF: WD2XSH/17 on WSPR] Content-Type: multipart/alternative; boundary="----=_NextPart_000_00F0_01CB7E7F.5F104800" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.7 required=5.0 tests=HTML_40_50,HTML_FONTCOLOR_BLUE, HTML_MESSAGE,MAILTO_TO_SPAM_ADDR,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-global-disposition: G x-aol-sid: 3039ac1d40944cd6a95b0310 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : temperror ------=_NextPart_000_00F0_01CB7E7F.5F104800 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ok Dave, So much for the skip theory , unless its leaking out of the grou= nd , may be the channel tunnel is acting as a large coax cable = =20 if you have a high noise level to start with , +10 is not good = news , may be the original wspr slot at the top of the band is= still the better option , pity the tx time is so long , its not really= matched to LF , if you only capture regularly 25% of the sync= =20 then sending the other 75% is questionable ? G..=20 From: Dave G3WCB.=20 Sent: Sunday, November 07, 2010 8:25 AM To: rsgb_lf_group@blacksheep.org=20 Subject: Wideband Noise on 500 kHz [was RE: LF: WD2XSH/17 on WSPR] Graham, LF,=20 I checked the wideband noise at midnight last night with my SPM-30 (3= kHz bandwidth). It was clearly audible, and had the sort of buzz-saw= rumble that one finds on HF occasionally. The levels were:- 496.0 kHz - 81 dBm 500.0 kHz - 73dBm 504.0 kHz - 83 dBm So it's about 8 to 10 dB above my local background noise level :-( No WSPR stations copied last night on 501 kHz. 73, Dave G3WCB IO91RM nr Windsor, S.E. England -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group= @blacksheep.org]On Behalf Of Graham Sent: 06 November 2010 13:22 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: WD2XSH/17 on WSPR Dave, I think the sharp cut-off is the only elegant part of it ? , usi= ng spec-lab , I can see a drop of 10 to 15 dB over 502 KHz .. sup= pose its a good place to try data modes out .. interestingly , wspr= is not producing any false decodes and the WD signal decoded tw= ice , which I think is actually times 4 decodes , round 2400 z , bu= t may be the s/n distorted by the noise floor increase ? my 100 wat= ts crossed once , but gave a better s/n=20 There may be a possibility , that you are inside the skip range= and out of the ground 75/100 mile range ..? I see a couple of S points on the meter as I tune over the noise= ..marvellous .. and the pulse modulated Christmas lights are yet= to come ...... hum-bug 73-G. From: Dave G3WCB.=20 Sent: Saturday, November 06, 2010 12:43 PM To: rsgb_lf_group@blacksheep.org=20 Subject: RE: LF: WD2XSH/17 on WSPR Hi, Graham. It's probably contributing to the overall high level of crud at this= QTH, but I'm not aware of exactly how much it is adding.=20 I'll do some tests over the week-end and try to measure the contribu= tion. From what I've seen on the various grabbers, it seems to have a= fairly well-defined H F cut-off, so it should be easy to identify whe= re the wideband datalink noise ends and the usual hash continues. Cheers Dave -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_gro= up@blacksheep.org]On Behalf Of Graham Sent: 06 November 2010 11:07 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: WD2XSH/17 on WSPR Dave, Do you see the wide band noise at + 10 to +15 dB over the ba= ckground noise ?=20 G..=20 From: Dave G3WCB.=20 Sent: Saturday, November 06, 2010 8:23 AM To: rsgb_lf_group@blacksheep.org ; GQRP@yahoogroups.com=20 Subject: LF: WD2XSH/17 on WSPR I snagged WD2XSH/17 last night on WSPR. This is pretty good going= for this QTH, as I have a very high local noise level on 500 kHz. 2010-11-06 04:06 WD2XSH/17 0.501091 -27 0 FN42pb +30 1.00= 0 G3WCB IO91rm 5233 3252 =20 73, Dave G3WCB IO91RM nr Windsor, S.E.England ------=_NextPart_000_00F0_01CB7E7F.5F104800 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ok Dave,
 
So much  for the  skip = ; theory ,=20 unless  its  leaking out of the  ground , may be the&nb= sp;=20 channel tunnel  is  acting as a  large  coax cable= =20  
 
if you  have a high  noise= level to =20 start with  , +10  is not good  news , may be the = =20 original  wspr  slot  at the  top  of the&nbs= p; band is=20 still
the  better  option , pity= the  tx=20 time is  so long , its not really matched to  LF , if= you =20 only  capture regularly   25% of the  sync =
then  sending the  other 75= % is=20 questionable ?
 
G..

Sent: Sunday, November 07, 2010 8:25 AM
Subject: Wideband Noise on 500 kHz [was RE: LF: WD2XSH/17= on=20 WSPR]

Graham, LF,
 
I=20 checked the wideband noise at midnight last night with my SPM-30 (3 kH= z=20 bandwidth). It was clearly audible, and had the sort of buzz-saw rumbl= e that one=20 finds on HF occasionally. The levels were:-
496.0 kHz    - 81=20 dBm
500.0 kHz    -=20 73dBm
504.0 kHz    - 83=20 dBm
=
So=20 it's about 8 to 10 dB above my local background noise level=20 :-(
 
No=20 WSPR stations copied last night on 501 kHz.
 
73,=20 Dave G3WCB IO91RM nr Windsor, S.E. England
-----Original Message-----
From:=20 owner-rsgb_lf_group@blacksheep.org=20 [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of=20 Graham
Sent: 06 November 2010 13:22
To:=20 rsgb_lf_group@blacksheep.org
Subject: Re: LF: WD2XSH/17 on= =20 WSPR

Dave,
 
I think the  sharp cut-off&nbs= p;  is=20 the only elegant  part of it ? , using  spec-lab , I can&n= bsp; see=20 a  drop  of 10  to 15 dB over 502 KHz .. suppose its= a=20 good  place to  try data modes out .. interestingly , wspr= is=20 not  producing any  false  decodes and the  WD= =20 signal  decoded  twice , which I think is =20 actually  times 4 decodes , round  2400 z , but may= be=20 the  s/n  distorted by the  noise floor increase ? my= 100=20 watts  crossed once , but  gave a  better s/n =
 
There  may be a possibility ,= that you=20 are  inside the  skip  range and out of the  gro= und =20 75/100  mile  range ..?
 
I see  a  couple of S poi= nts on=20 the  meter as I tune over the  noise ..marvellous .. and= =20 the  pulse modulated  Christmas  lights are = ; yet=20 to  come   ...... hum-bug
 
73-G.

Sent: Saturday, November 06, 2010 12:43 PM
Subject: RE: LF: WD2XSH/17 on WSPR

Hi,=20 Graham.
 
It's=20 probably contributing to the overall high level of crud at this QTH,= but I'm=20 not aware of exactly how much it is adding.
 
I'll=20 do some tests over the week-end and try to measure the contribution.= From what=20 I've seen on the various grabbers, it seems to have a fairly well-de= fined H F=20 cut-off, so it should be easy to identify where the wideband datalin= k noise=20 ends and the usual hash continues.
 
Cheers
 
Dave
-----Original Message-----
From:= =20 owner-rsgb_lf_group@blacksheep.org=20 [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of=20 Graham
Sent: 06 November 2010 11:07
To:=20 rsgb_lf_group@blacksheep.org
Subject: Re: LF: WD2XSH/17= on=20 WSPR

Dave,
 
Do you  see  the wide= band noise=20  at  + 10 to  +15 dB over the  background = ; noise ?=20
 
G..
 

Sent: Saturday, November 06, 2010 8:23 AM
Subject: LF: WD2XSH/17 on WSPR

I=20 snagged WD2XSH/17 last night on WSPR. This is pretty good going fo= r this=20 QTH, as I have a very high local noise level on 500 kHz.
2010-11-06 04:06  WD2XSH/17 =  0.501091  -27  0 &n= bsp;FN42pb  +30 <= TD align=3D"right"> 1.000  G3WCB  IO91rm&nb= sp; 5233  3252  
 
73, Dave G3WCB IO91RM nr Windsor,=20 S.E.England






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