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[195.171.43.25]) by mx.google.com with ESMTP id gr2si7762667wib.29.2013.12.27.18.54.10 for ; Fri, 27 Dec 2013 18:54:11 -0800 (PST) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1VwjH3-0001hs-Vj for rs_out_1@blacksheep.org; Sat, 28 Dec 2013 02:05:09 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1VwjH3-0001hj-BG for rsgb_lf_group@blacksheep.org; Sat, 28 Dec 2013 02:05:09 +0000 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1VwjH0-0004t8-7G for rsgb_lf_group@blacksheep.org; Sat, 28 Dec 2013 02:05:08 +0000 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id rBS255sV001922 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sat, 28 Dec 2013 03:05:05 +0100 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id rBS255I5023720 for ; Sat, 28 Dec 2013 03:05:05 +0100 Message-ID: <52BE31C5.1050106@iup.uni-heidelberg.de> Date: Sat, 28 Dec 2013 03:04:53 +0100 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <02ca01cf028f$c157cf50$44076df0$@comcast.net> <52BDC10A.20409@iup.uni-heidelberg.de> <03b201cf0338$17855660$46900320$@comcast.net> In-Reply-To: <03b201cf0338$17855660$46900320$@comcast.net> X-Spam-Score: -1.3 (-) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Jim, More informations for you: http://abelian.org/vlf/ss111126/ ... if you haven't found the link yet. Paul Nicholson is certainly the man who can answer these VLF phase variation questions better than most of us can. Your way to write emails is somehow similar to Paul's emails, i find :-) So you may have a good communication :-) Ah and of course that link: https://sites.google.com/site/sub9khz/ if you don't know yet... [...] Content analysis details: (-1.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [129.206.100.212 listed in list.dnswl.org] -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: c96efc14f58f84aa05b44c520f48db32 Subject: Re: VLF: 8969.99 Content-Type: multipart/alternative; boundary="------------020007020204060500010908" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,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 Status: O X-Status: X-Keywords: X-UID: 3502 This is a multi-part message in MIME format. --------------020007020204060500010908 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Jim, More informations for you: http://abelian.org/vlf/ss111126/ ... if you haven't found the link yet. Paul Nicholson is certainly the man who can answer these VLF phase variation questions better than most of us can. Your way to write emails is somehow similar to Paul's emails, i find :-) So you may have a good communication :-) Ah and of course that link: https://sites.google.com/site/sub9khz/ if you don't know yet... Am 27.12.2013 20:15, schrieb hvanesce: > > Stefan, > > Thank you for the information. I was hoping for input from you and Uwe > on ERP and antenna angle, and your information is very helpful. > > Regarding antenna angle: > > I am hoping to detect T/A VLF signals, and a long integration time is > important. Without special integration algorithms, changes in phase of > the received signal limit maximum integration time. Even at T/A > distances, low antenna angles (angles far from vertical) can increase > the sensitivity of phase to day/night transitions and other > environmental/ionospheric factors, and thus limit maximum useful > integration time. All of the above is for a constant non-vertical > antenna angle; maximum useful integration time is even less when the > antenna angle varies. > > I don't have solid numbers for phase vs. antenna angle, orientation > and distance yet (the phase variations of interest are of multimodal > origin, so multimodal analysis is required), but the information that > you provided will help very much in converging to an estimate of > maximum useful integration time with conventional integration algorithms. > > For T/A VLF signal capture planning purposes, do you think that it > would be safe to say that, in the next year or so, most amateur > antennas long enough for potential T/A VLF communication will either > be nearly horizontal (fixed at both ends), or fixed at one end with a > variation in angles as in the example that you gave below? > Well, if they are horizontal, then they will be quite inefficient, except they are several km long. Vertical antennas will be always small compared to my 300m vertical. Most of the kite experiment were done with just a few 100W and just for a few hours. With that setup i did not manage a TA detection on VLF, not even in 424 uHz. But there were just 3 or 4 experiments in which i could have had the chance. Anyway, stay tuned! Is there a chance for you to transmit? 73, Stefan/DK7FC > If so I will plan for something to assess, manage and possibly improve > maximum integration time for the phase variations expectable from such > antennas. > > Thank you for the information that you provided and all of your > remarkable contributions to VLF and LF. > > 73, Jim AA5BW > --------------020007020204060500010908 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Jim,

More informations for you: http://abelian.org/vlf/ss111126/ ... if you haven't found the link yet. Paul Nicholson is certainly the man who can answer these VLF phase variation questions better than most of us can. Your way to write emails is somehow similar to Paul's emails, i find :-) So you may have a good communication :-)
Ah and of course that link: https://sites.google.com/site/sub9khz/  if you don't know yet...

Am 27.12.2013 20:15, schrieb hvanesce:

Stefan,

 

Thank you for the information. I was hoping for input from you and Uwe on ERP and antenna angle, and your information is very helpful.

 

Regarding antenna angle:

 

I am hoping to detect T/A VLF signals, and a long integration time is important. Without special integration algorithms, changes in phase of the received signal limit maximum integration time. Even at T/A distances, low antenna angles (angles far from vertical) can increase the sensitivity of phase to day/night transitions and other environmental/ionospheric  factors, and thus limit maximum useful integration time. All of the above is for a constant non-vertical antenna angle; maximum useful integration time is even less when the antenna angle varies.

 

I don’t have solid numbers for phase vs. antenna angle, orientation and distance yet (the phase variations of interest are of multimodal origin, so multimodal analysis is required), but the information that you provided will help very much in converging to an estimate of maximum useful integration time with conventional integration algorithms.

 

For T/A VLF signal capture planning purposes, do you think that it would be safe to say that, in the next year or so, most amateur antennas long enough for potential T/A VLF communication will either be nearly horizontal (fixed at both ends), or fixed at one end with a variation in angles as in the example that you gave below?

Well, if they are horizontal, then they will be quite inefficient, except they are several km long.
Vertical antennas will be always small compared to my 300m vertical. Most of the kite experiment were done with just a few 100W and just for a few hours. With that setup i did not manage a TA detection on VLF, not even in 424 uHz. But there were just 3 or 4 experiments in which i could have had the chance.

Anyway, stay tuned! Is there a chance for you to transmit?

73, Stefan/DK7FC

If so I will plan for something to assess, manage and possibly improve maximum integration time for the phase variations expectable from such antennas.  

 

Thank you for the information that you provided and all of your remarkable contributions to VLF and LF.

 

73,  Jim AA5BW

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