Return-Path: Received: from mtain-dg01.r1000.mx.aol.com (mtain-dg01.r1000.mx.aol.com [172.29.65.9]) by air-mc04.mail.aol.com (v129.4) with ESMTP id MAILINMC041-a92e4d7144a1375; Fri, 04 Mar 2011 14:59:29 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dg01.r1000.mx.aol.com (Internet Inbound) with ESMTP id BBD31380000AD; Fri, 4 Mar 2011 14:59:27 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Pvb8v-0000Q9-Qv for rs_out_1@blacksheep.org; Fri, 04 Mar 2011 19:58:29 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Pvb8u-0000Q0-NY for rsgb_lf_group@blacksheep.org; Fri, 04 Mar 2011 19:58:28 +0000 Received: from nm11-vm0.bullet.mail.ird.yahoo.com ([77.238.189.218]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1Pvb8s-0001xe-IM for rsgb_lf_group@blacksheep.org; Fri, 04 Mar 2011 19:58:28 +0000 Received: from [77.238.189.53] by nm11.bullet.mail.ird.yahoo.com with NNFMP; 04 Mar 2011 19:58:20 -0000 Received: from [212.82.108.120] by tm6.bullet.mail.ird.yahoo.com with NNFMP; 04 Mar 2011 19:58:20 -0000 Received: from [127.0.0.1] by omp1029.mail.ird.yahoo.com with NNFMP; 04 Mar 2011 19:58:20 -0000 X-Yahoo-Newman-Id: 610783.88658.bm@omp1029.mail.ird.yahoo.com Received: (qmail 3548 invoked from network); 4 Mar 2011 19:58:20 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btinternet.com; h=DKIM-Signature:Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=qdzPpYEwKbHOiut5t7vhqgT8nZEwVIFqxUUMMagcJ0Yh9ZpyMXq35U6eMewRrIOG4dX5xasv+GjHcW+aijBBUucHsfcfe2EXKuW4yjGx8c4rQ1HIRkDF2/Xy3whL1M2Lo5CK/Rn0lDzAAUZHnSjp3JEN+z/3o3DMkm3RumGnlgg= ; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=s1024; t=1299268700; bh=R+r1SfftjDFgq5fMAD44HdUFSzX165yt+tn5UC5kLnU=; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=GAL27FqPHXt23VFFDkv6BKBD4yHIJrxCRYoTMIyMZwvsct8iphU+BF/CtQohwZFxZE6zrzJ6RSEFbH7rAQLSxEadUrLh822JtFpG1tsf9+qYpBbSCdqBM1ZUO1xxYrt9Zm2LQOdtYkOhHH2qGTAw8dB2TVMBHRyJbBWxLKbNonY= Received: from IBM7FFA209F07C (c.ashby435@81.129.136.38 with login) by smtp818.mail.ird.yahoo.com with SMTP; 04 Mar 2011 19:58:20 +0000 GMT X-Yahoo-SMTP: .u8e2g.swBByWKjbpA3lR6Fw.2ZEQrJJpVsTSrpXLCffsPaCEMY- X-YMail-OSG: PNb5VIIVM1l1MG2ZCK1ivci4Xa21oVTT8tQ8hKh2vHmMK1p FPZPbBBrVTf.x8SySixEixNkY3fZUVVnglR2IBVaobyCeVSDJ_3pwqQV5Uc1 DiPns_huzXF_Yb.CNq1xj596c5ti0yaoPuzZz22w8z9p3D80v6RpjIULTE4D zansv2ue80zk1SQCVijdc36uhd8Vcz96sOjAwPJ9EDS5oE.OMgTKfIAcXCbi tm5TqMv5FLyp6d4iq.gmOrGOQUGf5.6_CspdBcArsF7sLQ6vJxmJ1JqAviiU VfwGcyTtDHksgrw-- X-Yahoo-Newman-Property: ymail-3 Message-ID: From: "Chris" To: References: Date: Fri, 4 Mar 2011 19:58:19 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5994 DomainKey-Status: good (testing) X-Spam-Score: 3.4 (+++) X-Spam-Report: autolearn=disabled,FORGED_MUA_OUTLOOK=3.36,HTML_MESSAGE=0.001,UNPARSEABLE_RELAY=0.001 Subject: LF: Re: Topband ionogram trace Content-Type: multipart/alternative; boundary="----=_NextPart_000_0017_01CBDAA6.822F37F0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: ** X-Spam-Status: No, hits=2.9 required=5.0 tests=FORGED_MUA_OUTLOOK, FROM_ENDS_IN_NUMS,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-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m020.2 ; domain : btinternet.com DKIM : fail x-aol-sid: 3039ac1d41094d71449f6902 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_0017_01CBDAA6.822F37F0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thanks Andy, great stuff. I think we can be pretty sure it was as you= suggested and not aircraft. If it was aircraft it would be there all the time presumably. Pete and I plan to repeat the test when we can, probably next week, wi= ll let you know if we see the same thing again. Vy 73, Chris, G4AYT. ----- Original Message -----=20 From: Andy Talbot=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Friday, March 04, 2011 7:18 PM Subject: LF: Topband ionogram trace Here's Peter's update on the 'unusual' topband split trace. Might= explain its cleanliness Andy www.g4jnt.com ---------- Forwarded message ---------- From: Peter Martinez Date: 4 March 2011 18:35 Subject: Re: Dopplergrams 12 years ago To: Andy Talbot Andy: I had a look at the QRSS sample that G4AYT captured. Around the same= time I was watching the signal from the Fairford ionosonde. This swee= ps from 1625kHz, through top-band and on up to 13MHz. At that time it= was clear that the Fcrit was getting down towards 2MHz so the F-layer= was rising rapidly so this would have been responsible for the increa= sing negative Doppler shift he was seeing on one of the traces. In fac= t the MUF on the Fairford-Kendal path dropped below 1.7MHz at about 3= am that night. There was also evidence of night-time sporadic-E. This= is sometimes known as Auroral sporadic E but it isn't 'auroral' in th= e sense we usually mean, but refers to patches of Es which drift south= from the Auroral oval, probably initiated by the same particle precip= itation that causes aurora. This Es activity could have been responsib= le for the non-Doppler-shifted trace that G4AYT saw. On a normal night= only the F-layer would be reflecting on top-band. Fairford now has a new ionosonde equipment, a Digisonde DPS-4D which= I find is much easier to 'eavesdrop' on. The Digisondes are pulse sou= nders with the receiver co-located with the transmitter with the recei= ver synchronised to the transmitter locally. They didn't need to be lo= cked to anything and they weren't stable. The new one behaves rather= better, stepping exactly 25kHz exactly every 640mS (locked to GPS).= I have my system stepping in sync and have some crude ionograms alrea= dy and have confirmed that the pulse timing is accurate and stable. Th= e next job is to implement the pulse-compression algorithm, which is= very similar to that used by LORAN C. This will give me real-time io= nograms again, a facility I lost when the UK chirpsounders closed down= last year.=20 73 Peter ----- Original Message ----- From: "Andy Talbot" To: Sent: Thursday, March 03, 2011 7:59 PM Subject: Dopplergrams 12 years ago Hi Peter - Cast your mind back. We did some of the first Dopplergram tests= on 1967kHz back in 1998, and produced the plots shown http://www.g4jnt.com/Download/1967jnt1.jpg http://www.g4jnt.com/Download/1967jnt3.jpg http://www.g4jnt.com/Download/1967jnt4.jpg Can you recall the vertical span on the trace? As far as I recal= l, your EVM software decimated from 8kHz, then you set 80% of the samplinb= g rate as plot BW, so 3.125, 6.25Hz etc But t'would be interesting to= know for sure. Someone on the LF reflector (see below) has just posted the plot= of some QRSS topband tests, and was "surprised" to see the trace splitting= . So I looked out these to show what was done over a decade ago. Andy On 3 March 2011 18:55, Chris wrote: Hi All, Yesterday evening Pete, M0FMT, transmitted QRSS on topband for= a test. An unexpected effect was noticed with the trace splitting in two.= Nothing new or 'earth shattering' I expect, but new to us and worthy of furt= her experimentation. See the result and conclusion on my website http://qsl.net/g4ayt= on the bottom of page 1. I have never seen this effect on 137, even with quite strong aud= ible signals, maybe others have. Vy 73, Chris, G4AYT, Whitstable, UK. ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1204 / Virus Database: 1435/3479 - Release Date: 03/= 03/11=20 ------=_NextPart_000_0017_01CBDAA6.822F37F0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Thanks Andy, great stuff. I think we= can be pretty=20 sure it was as you suggested and not aircraft.
If it was aircraft it would be there= all the time=20 presumably.
Pete and I plan to repeat the test wh= en we can,=20 probably next week, will let you know if we see the same thing=20 again.
Vy 73,
Chris, G4AYT.
----- Original Message -----
From:=20 Andy=20 Talbot
Sent: Friday, March 04, 2011= 7:18=20 PM
Subject: LF: Topband ionogram= trace

Here's Peter's update on the 'unusual' topband split trace.&nbs= p; =20 Might explain its cleanliness
 
Andy
 
---------- Forwarded message ----------
From: Peter Martinez <peter.ma= rtinez@btinternet.com>
Date: 4 March=20 2011 18:35
Subject: Re: Dopplergrams 12 years ago
To: Andy Tal= bot <andy.g4jnt@gmail.com>


Andy:

I had a=20 look at the QRSS sample that G4AYT captured. Around the same time I= was=20 watching the signal from the Fairford ionosonde. This sweeps from 16= 25kHz,=20 through top-band and on up to 13MHz. At that time it was clear that= the Fcrit=20 was getting down towards 2MHz so the F-layer was rising rapidly so= this would=20 have been responsible for the increasing negative Doppler shift he= was seeing=20 on one of the traces. In fact the MUF on the Fairford-Kendal path dr= opped=20 below 1.7MHz at about 3 am that night. There was also evidence of ni= ght-time=20 sporadic-E. This is sometimes known as Auroral sporadic E but it isn= 't=20 'auroral' in the sense we usually mean, but refers to patches of Es= which=20 drift south from the Auroral oval, probably initiated by the same pa= rticle=20 precipitation that causes aurora. This Es activity could have been= responsible=20 for the non-Doppler-shifted trace that G4AYT saw. On a normal night= only the=20 F-layer would be reflecting on top-band.

Fairford now has a= new=20 ionosonde equipment, a Digisonde DPS-4D which I find is much easier= to=20 'eavesdrop' on. The Digisondes are pulse sounders with the receiver= co-located=20 with the transmitter with the receiver synchronised to the transmitt= er=20 locally. They didn't need to be locked to anything and they weren't= stable.=20 The new one behaves rather better, stepping exactly 25kHz exactly ev= ery 640mS=20 (locked to GPS). I have my system stepping in sync and have some cru= de=20 ionograms already and have confirmed that the pulse timing is accura= te and=20 stable. The next job is to implement the pulse-compression algorithm= , which is=20 very similar to that used by LORAN C.  This will give me real-t= ime=20 ionograms again, a facility I lost when the UK chirpsounders closed= down last=20 year.


73
Peter

----- Original Message ----- From:= "Andy=20 Talbot" <andy.g4jnt@gmail.com>
To: <peter.martinez@btintern= et.com>
Sent: Thursday, March=20 03, 2011 7:59 PM
Subject: Dopplergrams 12 years ago


Hi Peter -
Cast your mind back.  We did some of the= first=20 Dopplergram tests on 1967kHz
back in 1998, and produced the plo= ts=20 shown

http://www.g4jnt.com/Download/1967jnt1.jpg=
http://www.g4jnt.com/Download/1967jnt3.jpg
<= A href=3D"http://www.g4jnt.com/Download/1967jnt4.jpg" targ= et=3D_blank>http://www.g4jnt.com/Download/1967jnt4.jpg

Can= you=20 recall the vertical span on the trace?   As far as I recall,= =20 your
EVM software decimated from 8kHz, then you set 80% of the= samplinbg=20 rate
as plot BW, so 3.125, 6.25Hz etc    But t'would= be=20 interesting to know for
sure.

Someone on the LF reflecto= r (see=20 below)  has just posted the plot of some
QRSS topband test= s, and was=20 "surprised" to see the trace splitting.  So I
looked out= these to=20 show what was done over a decade ago.

Andy



O= n 3 March=20 2011 18:55, Chris <c.ashby435@btinternet.com> wrote:
 Hi= All,
Yesterday evening Pete, M0FMT,=20 transmitted QRSS on topband for a test. An
unexpected effect= was=20 noticed with the trace splitting in two. Nothing new
or 'eart= h=20 shattering' I expect, but new to us and worthy of=20 further
experimentation.
See the result and conclusion on= my website=20 http://qsl.net/= g4ayt on=20 the
bottom of page 1.
I have never seen this effect on 137= , even=20 with quite strong audible
signals, maybe others have.
Vy= =20 73,
Chris, G4AYT, Whitstable,=20 UK.




-----
No virus found in this message.
Checked by AVG -= www.avg.com=
Version:=20 10.0.1204 / Virus Database: 1435/3479 - Release Date: 03/03/11=20


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