Return-Path: Received: from mtain-dg11.r1000.mx.aol.com (mtain-dg11.r1000.mx.aol.com [172.29.65.19]) by air-de08.mail.aol.com (v129.4) with ESMTP id MAILINDE084-5ec14d5844f476; Sun, 13 Feb 2011 15:54:12 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dg11.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1265A38000094; Sun, 13 Feb 2011 15:54:10 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PoiwS-0005hX-NF for rs_out_1@blacksheep.org; Sun, 13 Feb 2011 20:53:12 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PoiwR-0005hO-SQ for rsgb_lf_group@blacksheep.org; Sun, 13 Feb 2011 20:53:11 +0000 Received: from imr-ma02.mx.aol.com ([64.12.206.40]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PoiwO-00067x-TI for rsgb_lf_group@blacksheep.org; Sun, 13 Feb 2011 20:53:11 +0000 Received: from mtaout-da01.r1000.mx.aol.com (mtaout-da01.r1000.mx.aol.com [172.29.51.129]) by imr-ma02.mx.aol.com (8.14.1/8.14.1) with ESMTP id p1DKqwAx009555 for ; Sun, 13 Feb 2011 15:52:58 -0500 Received: from White (nrbg-4dbe5560.pool.mediaWays.net [77.190.85.96]) by mtaout-da01.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id D1BB9E0000C2 for ; Sun, 13 Feb 2011 15:52:54 -0500 (EST) Message-ID: <26C9EC542E894224BD2972DCAE4E9432@White> From: "Markus Vester" To: References: Date: Sun, 13 Feb 2011 21:53:00 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 12.0.1606 X-MimeOLE: Produced By Microsoft MimeOLE V12.0.1606 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: Re: New Eu slot 136.177 kHz? Content-Type: multipart/alternative; boundary="----=_NextPart_000_0045_01CBCBC8.61F6C0D0" 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_20_30,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-global-disposition: G x-aol-sid: 3039ac1d41134d5844f201b9 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_0045_01CBCBC8.61F6C0D0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dear LF group, the considerations which led to the choice of a new Eu waterhole have= been explained in a posting from Dec 12th, attached beneath. Here's= a brief summary of the current situation:=20 - We clearly need separate E-W and W-E slots, due to side effects of= noise blanking, and imperfections of transmitters and receivers. - The Canadian West coast (Scott, Steve) experiences wide-area interfe= rence (presumably PLC), centered on 135700 and 136320. This is what tr= iggered the search for an alternative Eu slot. - Central and Eastern Europe suffers from HGA22 sidebands, except for= a few narrow slots (135.975, 136.177, 136.38) . The density of FSK te= legrams on DCF39 and HGA22 has been increasing. - We want to stay far enough from 137.0 in case CFH would be fired up= more regularly. - But we now have the problem that Jay is affected by local QRM around= 136.177. It consists.predominantly of a group of unstable lines, spac= ed by about 1 Hz. I had secretly hoped that Jay might ultimately find a way to identify= and fix the problem locally, but this may simply not be feasible. How= far up and down does this interference extend in frequency? I'm also= not sure whether Warren is actually having the same difficulty or not= . Now we have the dilemma that if we stay on the new slot, we may loose= many excellent high-quality observations from Jay. If we move back to= the old one, we give away the slim chance of being picked up by Scott= or his friends during that special Transpolar night.=20 The best choice may be to move on again. If we decide so, we will then= need to collect information regarding bad and good channels from all= key players, perhaps by detailed analysis of wav recordings of the wh= ole lower part of the band. Best regards, Markus (DF6NM) =20 From: Markus Vester=20 Sent: Sunday, December 12, 2010 3:13 PM To: rsgb_lf_group@blacksheep.org=20 Subject: New Eu slot 136.177 kHz? Dear LF, after considerations with Scott VE7TIL, Mike G3XDV, and Laurence KL7UK= , I would like to discuss moving the European intercontinental transmi= t slot. It is currently centered on 136.320 kHz, and I propose a new= center frequency of 136.177 kHz. This discussion was initiated by VE7TIL, who is plagued by severe QRM= lines, to an amount that he considers the vicinity of 136.32 kHz as= being unusable for him. Scott believes that the interference is cause= d by a PLC system leaking from a nearby powerline, and that it will pr= obably not be possible to fix it locally. Of course it can be disputed= whether QRM at one receive site would be reason enough to change a ba= nd plan, which has been useful for a number of years. On the other han= d, there is only a limited number of receivers around the world. And= we would certainly like to have Scott onboard, as the path from Eu to= the American West coast is certainly one of the most challenging ones= . A few years ago, we decided to move Eu transmissions from the original= 135922 Hz to 136320 Hz, driven by a wider gap in the American Loran-C= line spectrum. Since the shutdown of US and Canadian Loran chains, th= is is no longer an issue. One benefit of going back to a lower frequency would be moving further= away from the Canadian military transmitter CFH, which occasionally= sends out a strong FSK (or MSK) signal centered on 137.0 kHz. It woul= d be interesting to get some information how much this one actually af= fects the American LF background at different frequency offsets. Here in Europe and Russia, a possible disadvantage of going down is th= at we would also come closer to HGA22. This is the 100 kW telecontrol= transmitter in Budapest, an idle carrier sitting at 135.43 kHz, and= excursions to 135.77 during FSK bursts. Normally these bursts appear= every 11 seconds, but at times there are annoying blocks of consecuti= ve telegrams several minutes long. Here in Bavaria, the FSK modulation= sidebands are visibe up to about 136.5 kHz, but there are pronounced= spectral gaps due to the 200 bd modulation. These clear gaps are near= 135.97, 136.17 and 136.37 kHz.=20 We looked at 136.37 first, but this would not fix the problem for Scot= t. 135.97 seems worse in Europe due to Luxembourg effect impressed on= HGA, and is also getting close to the Greek military SXV. So we decid= ed to focus on 136.17 kHz. A closer look revealed that this very usefu= l FSK minimum is actually centered on 136177 Hz, and about 8 Hz wide. For the last few days, I have been running my grabber http://www.alice= -dsl.net/df6nm/grabber/Grabber.htm with a split window, showing both= the present and the proposed new slot side by side. The direct modula= tion sidebands (showing as red bands) are much better on the new frequ= ency. Nighttime Luxembourg QRM generally does not appear to be worse,= despite being closer to the HGA carrier. We also expect the latter to= be a more regionally confined effect, which will not be present in re= mote areas of the world. After all, the main purpose of Eu-slot grabbe= rs within Euroupe would not so much be ultimate sensitivity, but rathe= r to provide a monitor for intra-Eu transmit frequency coordination,= and a comparison log for verification of DX receptions.=20 Before coming to a possible decision to move the Eu frequency band, we= would like to collect some feedback on the receive situation in diffe= rent parts of the world. Traditionally, Eu slot transmissions were pri= marily targeted towards the American east coast. But of course we woul= d like to include other areas of the world. How useful would the propo= sed slot be for example in Russia or Japan?=20 Active Loran-C rates in Japan are GRI 8930 (lines at 136175.812 and 13= 68181.411 Hz) and GRI 9930 (lines at 136173.212 and 136178.248 Hz).= Russia uses GRI 8000 with lines at 6.25 Hz multiples, and perhaps GRI= 7950 (136178.157 Hz). As the frequencies are very accurate, these lin= es are very useful calibration markers. Now, your opinions please! Best regards, Markus (DF6NM) ------=_NextPart_000_0045_01CBCBC8.61F6C0D0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Dear LF group,
 
the considerations which led to= the choice of=20 a new Eu waterhole have been explained in a posting from Dec 12th= , attached=20 beneath. Here's a brief summary of the current situation: =
 
- We clearly need separate E-W and W-= E slots,=20 due to side effects of noise blanking, and imperfections=20 of transmitters and receivers.
 
- The Canadian West coast (Scott,=20 Steve) experiences wide-area interference (presumably PLC), cente= red on=20 135700 and 136320. This is what triggered the search for an=20 alternative Eu slot.
 
- Central and Eastern Europe suffers= =20 from HGA22 sidebands, except for a few narrow slots (13= 5.975,=20 136.177, 136.38) . The density of FSK telegrams on DCF39 and HGA22 has=  been=20 increasing.
 
- We want to stay far enough from 137= .0 in case CFH=20 would be fired up more regularly.
 
- But we now have the problem th= at Jay is=20 affected by local QRM around 136.177. It consists.predominantly= of a group=20 of unstable lines, spaced by about 1 Hz.
 
I had secretly hoped that Jay might&n= bsp;ultimately=20 find a way to identify and fix the problem locally, but this= may=20 simply not be feasible. How far up and down does this interference ext= end in=20 frequency? I'm also not sure whether Warren is actually having the sam= e=20 difficulty or not.
 
Now we have the dilemma that if= we stay on the=20 new slot, we may loose many excellent high-quality observations= from Jay.=20 If we move back to the old one, we give away the slim chance of=20 being picked up by Scott or his friends during that spe= cial=20 Transpolar night.
 
The best choice may be to m= ove on again.=20 If we decide so, we will then need to collect information regarding&nb= sp;bad and=20 good channels from all key players, perhaps by det= ailed=20 analysis of wav recordings of the whole lower part of the band.=
 
Best regards,
Markus (DF6NM)
 
   

From: Markus Vester
Sent: Sunday, December 12, 2010 3:13 PM
Subject: New Eu slot 136.177 kHz?
=
Dear LF,
 
after con= siderations with=20 Scott VE7TIL, Mike G3XDV, and Laurence KL7UK, I would like=20 to discuss moving the European intercontinental transmit slot. It= =20 is currently centered on 136.320 kHz, and I propose a= new center=20 frequency of 136.177 kHz.
 
This discussion was initiat= ed by VE7TIL,=20 who is plagued by severe QRM lines, to an amount that he consider= s the=20 vicinity of 136.32 kHz as being unusable for him. Scott believes= =20 that the interference is caused by a PLC system leaking= from a=20 nearby powerline, and that it will probably not be possible to fi= x it=20 locally. Of course it can be disput= ed whether QRM=20 at one receive site would be reason enough to change a band plan,= which has=20 been useful for a number of years. On the other hand, there is on= ly a=20 limited number of receivers around the world. And we would= certainly=20 like to have Scott onboard, as the path from Eu to the American West= coast is=20 certainly one of the most challenging ones.
 
A few years ago, we decided to move= Eu=20 transmissions from the original 135922 Hz to 136320 Hz, driven by=  a=20 wider gap in the American Loran-C line spectrum. Since the shutdown of= US and=20 Canadian Loran chains, this is no longer an issue.
 
One benefit of going back to a= lower frequency=20 would be moving further away from the Canadian military transmitter CF= H, which=20 occasionally sends out a strong FSK (or MSK) signal centered on 137.0= kHz. It=20 would be interesting to get some information how much this one ac= tually=20 affects the American LF background at different frequency offsets.
 
Here in Europe and Russia, a pos= sible=20 disadvantage of going down is that we would also come closer to HGA22.= This is=20 the 100 kW telecontrol transmitter in Budapest, an idle carrier= sitting at=20 135.43 kHz, and excursions to 135.77 during FSK bursts. Normally= these=20 bursts appear every 11 seconds, but at times there are annoying= blocks of=20 consecutive telegrams several minutes long. Here in Bavaria, the = FSK=20 modulation sidebands are visibe up to about 136.5 kHz, but there= are=20 pronounced spectral gaps due to the 200 bd modulation. These clea= r gaps=20 are near 135.97, 136.17 and 136.37 kHz.
 
We looked at 136.37 first,= but this would=20 not fix the problem for Scott. 135.97 seems worse in Europe due to Lux= embourg=20 effect impressed on HGA, and is also getting close to the Greek milita= ry SXV. So=20 we decided to focus on 136.17 kHz. A=20 closer look revealed that this very useful FSK=20 minimum is actually centered on 136177 Hz, and about 8 Hz=20 wide.
 
For the last few days, I have been ru= nning my=20 grabber http://www.alice-dsl.n= et/df6nm/grabber/Grabber.htm=20 with a split window, showing both the present and the proposed ne= w slot=20 side by side. The direct modulation sidebands (showing as red ban= ds) are=20 much better on the new frequency. Nighttime Luxembourg QRM genera= lly does=20 not appear to be worse, despite being closer to the HGA=20 carrier. We also expect the latter to be a more regionally= =20 confined effect, which will not be present in remote areas= of the=20 world. After all, the main purpose of Eu-slot grabbers within Euroupe= would=20 not so much be ultimate sensitivity, but rather to provide a moni= tor for=20 intra-Eu transmit frequency coordination, and a comparison log for ver= ification=20 of DX receptions.
 
Before coming to a possible decision to move the Eu frequency ban= d, we=20 would like to collect some feedback on the receive situation in differ= ent parts=20 of the world. Traditionally, Eu slot transmissions were primarily= targeted=20 towards the American east coast. But of course we would like= =20 to include other areas of the world. How useful would the pr= oposed=20 slot be for example in Russia or Japan?
 
Active Loran-C rates in Japan are GRI 8930 (lines at 136175.= 812 and=20 1368181.411 Hz) and GRI 9930 (lines at  136173.212 and 136178.248= Hz).=20 Russia uses GRI 8000 with lines at 6.25 Hz multiples, and pe= rhaps GRI=20 7950 (136178.157 Hz). As the frequencies are very accurate, these line= s=20 are very useful calibration markers.
 
Now, your opinions please!
 
Best regards,
Markus (DF6NM)
 
------=_NextPart_000_0045_01CBCBC8.61F6C0D0--