Return-Path: Received: from mtain-dc03.r1000.mx.aol.com (mtain-dc03.r1000.mx.aol.com [172.29.64.131]) by air-da09.mail.aol.com (v129.4) with ESMTP id MAILINDA093-86414d663fee157; Thu, 24 Feb 2011 06:24:30 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dc03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 0770838006741; Thu, 24 Feb 2011 06:16:22 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PsZ9c-0000AY-1M for rs_out_1@blacksheep.org; Thu, 24 Feb 2011 11:14:40 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PsZ9a-0000AP-N5 for rsgb_lf_group@blacksheep.org; Thu, 24 Feb 2011 11:14:38 +0000 Received: from imr-da01.mx.aol.com ([205.188.105.143]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PsZ9Z-00035C-8O for rsgb_lf_group@blacksheep.org; Thu, 24 Feb 2011 11:14:38 +0000 Received: from imo-ma02.mx.aol.com (imo-ma02.mx.aol.com [64.12.78.137]) by imr-da01.mx.aol.com (8.14.1/8.14.1) with ESMTP id p1OBEOWJ032076 for ; Thu, 24 Feb 2011 06:14:24 -0500 Received: from MarkusVester@aol.com by imo-ma02.mx.aol.com (mail_out_v42.9.) id l.eff.12c669fa (34953) for ; Thu, 24 Feb 2011 06:14:16 -0500 (EST) Received: from smtprly-de03.mx.aol.com (smtprly-de03.mx.aol.com [205.188.249.170]) by cia-da06.mx.aol.com (v129.9) with ESMTP id MAILCIADA062-b2524d663d85104; Thu, 24 Feb 2011 06:14:16 -0500 Received: from Webmail-m108 (webmail-m108.sim.aol.com [64.12.232.213]) by smtprly-de03.mx.aol.com (v129.9) with ESMTP id MAILSMTPRLYDE036-b2524d663d85104; Thu, 24 Feb 2011 06:14:13 -0500 References: To: rsgb_lf_group@blacksheep.org Date: Thu, 24 Feb 2011 06:14:12 -0500 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: Markus Vester X-MB-Message-Type: User X-Mailer: AOL Webmail 33298-STANDARD Received: from 194.138.39.52 by Webmail-m108.sysops.aol.com (64.12.232.213) with HTTP (WebMailUI); Thu, 24 Feb 2011 06:14:12 -0500 Message-Id: <8CDA22B19CD407E-1FB0-820@Webmail-m108.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: MarkusVester@aol.com X-Spam-Score: 0.3 (/) X-Spam-Report: autolearn=disabled,FORGED_AOL_TAGS=0.281,HTML_MESSAGE=0.001,UNPARSEABLE_RELAY=0.001 Subject: LF: Proposed Eu waterhole center 136.172 kHz Content-Type: multipart/alternative; boundary="--------MB_8CDA22B19D464A1_1FB0_FDD_Webmail-m108.sysops.aol.com" 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=FORGED_AOL_TAGS,HTML_20_30, HTML_FONTCOLOR_UNKNOWN,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: 3039ac1d40834d663e0674d4 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ----------MB_8CDA22B19D464A1_1FB0_FDD_Webmail-m108.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Dear LF, after some detailed investigation of the interference situation at W1VD an= d VE7TIL, we propose to move down the recommended Eu TX slot by 5 Hz, from= the current center frequency 136177 to 136172 Hz. The latter seems to be= clear for Jay within about +-4 Hz (ie 136168 to 136176 Hz). HGA sidebands= in Europe are no worse as we are still within their spectral gap. I would ask all interested receive stations to include this range in their= observations, and look for possible interference at this QRG. If no serio= us problem pops up, we could all shift our grabber slots. Best 73, MArkus (DF6NM) -----Urspr=C3=BCngliche Mitteilung-----=20 Von: Markus Vester An: rsgb_lf_group@blacksheep.org Verschickt: So., 13. Feb. 2011, 21:53 Thema: Re: New Eu slot 136.177 kHz? Dear LF group, =20 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 su= mmary of the current situation:=20 =20 - We clearly need separate E-W and W-E slots, due to side effects of noise= blanking, and imperfections of transmitters and receivers. =20 - The Canadian West coast (Scott, Steve) experiences wide-area interferenc= e (presumably PLC), centered on 135700 and 136320. This is what triggered= the search for an alternative Eu slot. =20 - Central and Eastern Europe suffers from HGA22 sidebands, except for a fe= w narrow slots (135.975, 136.177, 136.38) . The density of FSK telegrams= on DCF39 and HGA22 has been increasing. =20 - We want to stay far enough from 137.0 in case CFH would be fired up more= regularly. =20 - 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, spaced by ab= out 1 Hz. =20 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 wh= ether Warren is actually having the same difficulty or not. =20 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 frie= nds during that special Transpolar night.=20 =20 The best choice may be to move on again. If we decide so, we will then nee= d to collect information regarding bad and good channels from all key play= ers, perhaps by detailed analysis of wav recordings of the whole lower par= t of the band. =20 Best regards, Markus (DF6NM) =20 =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, =20 after considerations with Scott VE7TIL, Mike G3XDV, and Laurence KL7UK, I= would like to discuss moving the European intercontinental transmit slot.= It is currently centered on 136.320 kHz, and I propose a new center frequ= ency of 136.177 kHz. =20 This discussion was initiated by VE7TIL, who is plagued by severe QRM line= s, to an amount that he considers the vicinity of 136.32 kHz as being unus= able for him. Scott believes that the interference is caused by a PLC syst= em leaking from a nearby powerline, and that it will probably not be possi= ble to fix it locally. Of course it can be disputed whether QRM at one rec= eive site would be reason enough to change a band plan, which has been use= ful for a number of years. On the other hand, there is only a limited numb= er of receivers around the world. And we would certainly like to have Scot= t onboard, as the path from Eu to the American West coast is certainly one= of the most challenging ones. =20 A few years ago, we decided to move Eu transmissions from the original 135= 922 Hz to 136320 Hz, driven by a wider gap in the American Loran-C line sp= ectrum. Since the shutdown of US and Canadian Loran chains, this is no lon= ger an issue. =20 One benefit of going back to a lower frequency would be moving further awa= y from the Canadian military transmitter CFH, which occasionally sends out= a strong FSK (or MSK) signal centered on 137.0 kHz. It would be interesti= ng to get some information how much this one actually affects the American= LF background at different frequency offsets. =20 Here in Europe and Russia, a possible disadvantage of going down is that= we would also come closer to HGA22. This is the 100 kW telecontrol transm= itter in Budapest, an idle carrier sitting at 135.43 kHz, and excursions= to 135.77 during FSK bursts. Normally these bursts appear every 11 second= s, but at times there are annoying blocks of consecutive 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 =20 We looked at 136.37 first, but this would not fix the problem for Scott.= 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 decided to foc= us on 136.17 kHz. A closer look revealed that this very useful FSK minimum= is actually centered on 136177 Hz, and about 8 Hz wide. =20 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 prese= nt and the proposed new slot side by side. The direct modulation sidebands= (showing as red bands) are much better on the new frequency. Nighttime Lu= xembourg 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 con= fined effect, which will not be present in remote areas of the world. Afte= r all, the main purpose of Eu-slot grabbers within Euroupe would not so mu= ch be ultimate sensitivity, but rather to provide a monitor for intra-Eu= transmit frequency coordination, and a comparison log for verification of= DX receptions.=20 =20 Before coming to a possible decision to move the Eu frequency band, we wou= ld like to collect some feedback on the receive situation in different par= ts of the world. Traditionally, Eu slot transmissions were primarily targe= ted towards the American east coast. But of course we would like to includ= e other areas of the world. How useful would the proposed slot be for exam= ple in Russia or Japan?=20 =20 Active Loran-C rates in Japan are GRI 8930 (lines at 136175.812 and 136818= 1.411 Hz) and GRI 9930 (lines at 136173.212 and 136178.248 Hz). Russia us= es GRI 8000 with lines at 6.25 Hz multiples, and perhaps GRI 7950 (136178.= 157 Hz). As the frequencies are very accurate, these lines are very useful= calibration markers. =20 Now, your opinions please! =20 Best regards, Markus (DF6NM) =20 ----------MB_8CDA22B19D464A1_1FB0_FDD_Webmail-m108.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
Dear LF,
 
after some detailed investigation of the interference situation= at W1VD and VE7TIL, we propose to move down the recommended Eu TX sl= ot by 5 Hz, from the current center frequency 136177 to 136172 Hz. Th= e latter seems to be clear for Jay within about +-4 Hz (ie 13616= 8 to 136176 Hz). HGA sidebands in Europe are no worse as we are= still within their spectral gap.
 
I would ask all interested receive stations to include this range in= their observations, and look for possible interference at this QRG. = If no serious problem pops up, we could all shift our grabber slots.<= /div>
 
Best 73,
MArkus (DF6NM)

-----Urspr=C3=BCngliche Mitteilung-----
Von: Markus Vester <markusvester@aol.com>
An: rsgb_lf_group@blacksheep.org
Verschickt: So., 13. Feb. 2011, 21:53
Thema: Re: New Eu slot 136.177 kHz?

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 situati= on: 
 
- We clearly need separate E-W and W-E sl= ots, due to side effects of noise blanking, and imperfections of=  transmitters and receivers.
 
- The Canadian West coast (Scott, Steve)&= nbsp;experiences wide-area interference (presumably PLC), centered on 1357= 00 and 136320. This is what triggered the search for an alternative&n= bsp;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 telegrams on DCF39 and HGA22 has&nb= sp;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.predominant= ly of a group of unstable lines, spaced 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 interf= erence 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 obser= vations from Jay. If we move back to the old one, we give away the slim ch= ance of being picked up by Scott or his friends during that= special Transpolar night.
 
The best choice may be to move= on again. If we decide so, we will then need to collect information regar= ding bad and good channels from all key players, perhaps&nb= sp;by detailed analysis of wav recordings of the whole lower part of= the band.
 
Best regards,
Markus (DF6NM)
 
   

Sent: Sunday, December 12, 2010 3:13 PM
Subject: New Eu slot 136.177 kHz?

Dear LF,
 
after conside= rations with Scott VE7TIL, Mike G3XDV, and Laurence KL7UK, I would= like to discuss moving the European intercontinental transmit 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. Scot= t believes that the interference is caused by a PLC system= leaking from a nearby powerline, and that it will probably not be po= ssible to fix it locally. Of course it= can be disputed whether QRM at one receive site would be reason enough to= change a band plan, which has been useful for a number of years.&nbs= p;On the other hand, there is only a limited number of receivers arou= nd 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 tr= ansmissions 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, this is no longer an issue.
 
One benefit of going back to a lower= frequency would be moving further away from the Canadian military transmi= tter CFH, which occasionally sends out a strong FSK (or MSK) signal center= ed on 137.0 kHz. It would be interesting to get some information how much= this one actually affects the American LF background at different fr= equency offsets.
 
Here in Europe and Russia, a possibl= e disadvantage of going down is that we would also come closer to HGA22.= This is the 100 kW telecontrol transmitter in Budapest, an idle carr= ier 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&nb= sp;annoying blocks of consecutive 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 modula= tion. These clear gaps are near 135.97, 136.17 and 136.37 kHz.=
 
We looked at 136.37 first, but= this would not fix the problem for Scott. 135.97 seems worse in Europe du= e to Luxembourg effect impressed on HGA, and is also getting close to the= Greek military SXV. So we decided to focus on 136.17 kHz. A closer l= ook revealed that this very useful FSK minimum is actu= ally centered on 136177 Hz, and about 8 Hz wide.
 
For the last few days, I have been runnin= g my grabber http://ww= w.alice-dsl.net/df6nm/grabber/Grabber.htm with a split window, showing= both the present and the proposed new slot side by side. The di= rect modulation sidebands (showing as red bands) are much better on the ne= w frequency. Nighttime Luxembourg QRM generally does not appear to&nb= sp;be worse, despite being closer to the HGA carrier. We also ex= pect the latter to be a more regionally confined effect, which&n= bsp;will not be present in remote areas of the world. After all, the main= purpose of Eu-slot grabbers within Euroupe would not so much be ulti= mate sensitivity, but rather to provide a monitor for intra-Eu transmit fr= equency coordination, and a comparison log for verification of DX receptio= ns.
 
Before coming to a possible decision to move the Eu frequency band,= we would like to collect some feedback on the receive situation in differ= ent parts of the world. Traditionally, Eu slot transmissions were pri= marily targeted towards the American east coast. But of course we wou= ld like to include other areas of the world. How useful wou= ld the proposed slot be for example in Russia or Japan?
 
Active Loran-C rates in Japan are GRI 8930 (lines at 136175.812= and 1368181.411 Hz) and GRI 9930 (lines at  136173.212 and 136178.24= 8 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 lines are very useful calibration markers.
 
Now, your opinions please!
 
Best regards,
Markus (DF6NM)
 
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