Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=5.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,RCVD_IN_DNSWL_MED, SPF_PASS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: : mailn 1480; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id uBV1AdmI007747 for ; Sat, 31 Dec 2016 02:10:41 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1cN88s-0004w1-Pt for rs_out_1@blacksheep.org; Sat, 31 Dec 2016 01:07:26 +0000 Received: from [195.171.43.34] (helo=relay2.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1cN88s-0004vs-6m for rsgb_lf_group@blacksheep.org; Sat, 31 Dec 2016 01:07:26 +0000 Received: from omr-a019e.mx.aol.com ([204.29.186.67]) by relay2.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.87) (envelope-from ) id 1cN88m-00056R-HD for rsgb_lf_group@blacksheep.org; Sat, 31 Dec 2016 01:07:25 +0000 Received: from mtaomg-aab01.mx.aol.com (mtaomg-aab01.mx.aol.com [172.26.126.207]) by omr-a019e.mx.aol.com (Outbound Mail Relay) with ESMTP id 95FF23800092 for ; Fri, 30 Dec 2016 20:07:18 -0500 (EST) Received: from core-acx02h.mail.aol.com (core-acx02.mail.aol.com [10.76.5.147]) by mtaomg-aab01.mx.aol.com (OMAG/Core Interface) with ESMTP id C19A238000084 for ; Fri, 30 Dec 2016 20:07:17 -0500 (EST) Received: from 188.192.95.60 by webprd-m96.mail.aol.com (10.74.63.53) with HTTP (WebMailUI); Fri, 30 Dec 2016 20:07:17 -0500 Date: Fri, 30 Dec 2016 20:07:17 -0500 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <159526aa32e-1297-2d056@webprd-m96.mail.aol.com> In-Reply-To: <58668A5B.1080206@posteo.de> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [188.192.95.60] x-aol-global-disposition: G X-AOL-VSS-INFO: 5800.7501/113682 X-AOL-VSS-CODE: clean DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1483146438; bh=N53ktDAQDG6cc+u/k5BzljaRjqcI9jgw5LajMaEcvm8=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=Qpp7PjAZwHbM0daa7VxkssrwgrLl1GiUtJLHdmUClhSCerUT0VKLHKexRdr2my6OZ ylaB9E906+/vDwsxA9dhPaKnZ9OKwSDtKhGBF0RmK1G5GaS6yaExOIEAp5HAq0iNHh 3nUyIFQWYs+cA8ac5ePaI9dU1A8MU1pIyUt7B6Vg= x-aol-sid: 3039ac1a7ecf586704c545dd X-Scan-Signature: 81978068c3ed22c636bd574cc661f8bd Subject: Re: VLF: Back on 5.17 kHz / 58 km... Content-Type: multipart/mixed; boundary="----=_Part_229728_1966990708.1483146437420" 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-Scanned-By: MIMEDefang 2.75 Status: O X-Status: X-Keywords: X-UID: 10020 ------=_Part_229728_1966990708.1483146437420 Content-Type: multipart/alternative; boundary="----=_Part_229727_2115785162.1483146437420" ------=_Part_229727_2115785162.1483146437420 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Stefan, during the last hours a good peak apperared here, around 13 dB in 63 uHz. I= f this is really your carrier (and not just a local GPS harmonic), tomorrow= 's EbNaut sequence should become an easy decode. Nice video! Best 73, Markus (DF6NM) =20 -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: Fr, 30 Dez 2016 5:27 pm Betreff: Re: VLF: Back on 5.17 kHz / 58 km... Hi VLF,=20 I managed to resonate my antenna on 5170 Hz. It was necessary to increase = the inductance from 1.2 H to 2 H. This was done by increasing the number of= iron powder cores (T106-52) from 100 to 176! It is the coil out of 10 stac= ked yoghurt cups that i got from Markus (many thanks again!). An image from= the stacked cores into the coil: https://dl.dropboxusercontent.com/u/19882= 028/VLF/20161229_194850.jpg Although the number of turns of this coil is constant and the stacking hei= ght is even higher (means a lower coupling of the coils and so they must ha= ve a lower L), the inductance is higher now. So this increase must come fro= m the cores. I clearly saw that the Q is significantly higher now, so the c= ores are a good choice for any VLF band. Also i need less power now. It als= o means that the proximity effect must be lower now (due to the lower coupl= ing), because the Q is higher and the antenna current and the R(DC) of the = coils is the same as on 6470 Hz. Now i'm running 230 mA since 14:40 UTC. I intend to run it until 8 UTC, th= en a first EbNaut message follows. The antenna voltage increased from 11.3 kV to 14.2 kV @ 230 mA. So far the= antenna current is not really stable but it becomes foggy outside and i di= d not yet add the transductor to the system. Maybe i'm trying to build an A= LC into SpecLab. This should work well now with the new interpreter command= for the bypass factor of the delay line :-) Ah there is even a short video (6 sec, 1.2 MB) where you can see and hear = (!) the coil and its internal fan on the roof while running at 14 kV: http:= //www.iup.uni-heidelberg.de/schaefer_vlf/VLF/VLF_coil_at_230mA_14kV_5170Hz.= mp4 (hopefully the link works). Lets be optimistic, i'm announcing the first EbNaut message for tomorrow: f =3D 5170.000000 Hz Start time: 31.12.2016 09:00:00 UTC Symbol length: 60 s Characters: 2 CRC 16 Coding 8K19A Duration: 6h, 08m, 0s Antenna current: ~ 230 mA 73, Stefan Am 27.12.2016 12:36, schrieb DK7FC:=20 Hi VLF,=20 It's time to come back to 5.17 kHz where i have been in the last kite expe= riments 2010/2011. The best result was about 10 dB in 3.8 mHz in 904 km dis= tance, detected by SQ5BPF. His website about this experiment is still on th= e web, http://www.lipkowski.org/~sq5bpf/dk7fc_20101023/index_en.html=20 In these kite tests my ERP was about 3 mW on 5170 Hz. But this was with a = 300m vertical antenna!=20 With my fixed antenna i can never radiate such strong signals. The limitin= g factor is the coil which can handle 250 mA on that frequency. The radiati= on resistance is about 210 uOhm, so the ERP will be up to 23 uW. So this is= 20 dB weaker (oh, actually i expected it is even more weaker). But on the = fixed antenna it is no problem to transmit 100x longer!!=20 We will see what is possible on that band with such a low power. Who wants= to make a guess? :-)=20 But i'm not yet sure if i can resonate the antenna down there at all. The = plan is to use the small coil that was used for 6470 Hz. Inside the coil th= ere are 100 iron powder cores, shown here https://dl.dropboxusercontent.com= /u/19882028/VLF/20160415_155753.jpg and here https://dl.dropboxusercontent.= com/u/19882028/VLF/20160415_163021.jpg I want to replace (a few) of them b= y ferrite cores, many ferrite cores "switched in parallel". I need to get t= he inductance down from 1.2 H to 2.0 H. So first the ferrite cores much pro= vide a higher effective =C2=B5r (ur) which is no problem i guess. Secondly = the must not saturate (to much), which is the critical question here. We wi= ll see what happens...=20 It's the right time in the year for such a work and i think i can do a fir= st transmission on 58 km during this week...=20 73, Stefan ------=_Part_229727_2115785162.1483146437420 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Hi Stefan,

during the last hours a good peak appe= rared here, around 13 dB in 63 uHz. If this is really your carrier (and not= just a local GPS harmonic), tomorrow's EbNaut sequence should be= come an easy decode.

Nice video!

Best 73,
Markus (DF6NM)
 


-----Urspr=C3=BCngliche Mitteilung-----
Von: DK= 7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@b= lacksheep.org>
Verschickt: Fr, 30 Dez 2016 5:27 pm
Betreff: Re: VL= F: Back on 5.17 kHz / 58 km...

Hi VLF,

I managed to resonate my antenna on 5170 Hz. It was necessary to increase the inductance from 1.2 H to 2 H. This was done by increasing the number of iron powder cores (T106-52) from 100 to 176! It is the coil out of 10 stacked yoghurt cups that i got from Markus (many thanks again!). An image from the stacked cores into the coil: https://dl.dropboxusercontent.com/u/19882028/VLF/20161229_= 194850.jpg
Although the number of turns of this coil is constant and the stacking height is even higher (means a lower coupling of the coils and so they must have a lower L), the inductance is higher now. So this increase must come from the cores. I clearly saw that the Q is significantly higher now, so the cores are a good choice for any VLF band. Also i need less power now. It also means that the proximity effect must be lower now (due to the lower coupling), because the Q is higher and the antenna current and the R(DC) of the coils is the same as on 6470 Hz.

Now i'm running 230 mA since 14:40 UTC. I intend to run it until 8 UTC, then a first EbNaut message follows.
The antenna voltage increased from 11.3 kV to 14.2 kV @ 230 mA. So far the antenna current is not really stable but it becomes foggy outside and i did not yet add the transductor to the system. Maybe i'm trying to build an ALC into SpecLab. This should work well now with the new interpreter command for the bypass factor of the delay line :-)
Ah there is even a short video (6 sec, 1.2 MB) where you can see and hear (!) the coil and its internal fan on the roof while running at 14 kV: http://www.iup.uni-heidelberg.de/schaefer_v= lf/VLF/VLF_coil_at_230mA_14kV_5170Hz.mp4 (hopefully the link works).

Lets be optimistic, i'm announcing the first EbNaut message for tomorrow:

f =3D 5170.000000 Hz
Start time: 31.12.2016   09:00:00 UTC
Symbol length: 60 s
Characters: 2
CRC 16
Coding 8K19A
Duration: 6h, 08m, 0s
Antenna current: ~ 230 mA


73, Stefan



Am 27.12.2016 12:36, schrieb DK7FC:
Hi VLF,

It's time to come back to 5.17 kHz where i have been in the last kite experiments 2010/2011. The best result was about 10 dB in 3.8 mHz in 904 km distance, detected by SQ5BPF. His website about this experiment is still on the web, http://www.lipkowski.org/~sq5bpf/dk7fc_20101023/index_en.html

In these kite tests my ERP was about 3 mW on 5170 Hz. But this was with a 300m vertical antenna!
With my fixed antenna i can never radiate such strong signals. The limiting factor is the coil which can handle 250 mA on that frequency. The radiation resistance is about 210 uOhm, so the ERP will be up to 23 uW. So this is 20 dB weaker (oh, actually i expected it is even more weaker). But on the fixed antenna it is no problem to transmit 100x longer!!
We will see what is possible on that band with such a low power. Who wants to make a guess? :-)

But i'm not yet sure if i can resonate the antenna down there at all. The plan is to use the small coil that was used for 6470 Hz. Inside the coil there are 100 iron powder cores, shown here https://dl.dropboxusercontent.com/u/19882028/VLF/20160415_= 155753.jpg and here https://dl.dropboxusercontent.com/u/19882028/VLF/20160415_= 163021.jpg  I want to replace (a few) of them by ferrite cores, many ferrite cores "switched in parallel". I need to get the inductance down from 1.2 H to 2.0 H. So first the ferrite cores much provide a higher effective =C2=B5r (ur) which is no problem i guess. Secondly the must not saturate (to much), which is the critical question here. We will see what happens...

It's the right time in the year for such a work and i think i can do a first transmission on 58 km during this week...

73, Stefan



------=_Part_229727_2115785162.1483146437420-- ------=_Part_229728_1966990708.1483146437420 Content-Type: image/png; name=peak_5170Hz_63uHz_161230_2336.png Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename=peak_5170Hz_63uHz_161230_2336.png iVBORw0KGgoAAAANSUhEUgAAAJEAAADTCAMAAAC2lgF2AAADAFBMVEUAAAATA20DA2YBA2gDA1sD A1YNA2wEBAT///9AQEAHA2oYA24iA3EDA0oAA2ceA3ADA1EnA3EDA2ADAzgzA3EtA3EDA0MDAz45 A3E+A3AEBCP//wBEA3ADAzEDAypIA28EBBxOA29TA24EBBYEBBEEBApZA25fA21kA2zAwMBqA2tu A2p0BGh5CmR/EWH///6FGF2KHlmQJVWaME2UKlKfN0hmAACrRD0AAGalPkOwSzi2UjO2/7a6Vi/A XCoAgADFYiXLaCDRbhvXdBfaeRTgfw3mhQ3riwvxkQr3lwf9nQb/oQZMAAC2ZgD/pgRmtv8AADr/ qwT/sQT/tgQAABn/uwQAAEwZAAC2//+Q2///wAT//7ZspYk6AADbkDr/wwSQOgAuQS7/zgQAOpAA Zrb/tmb/0wT/25AlDgArbKX/yARsKwA6kNsAK2z/2AT/3AQOAAAADiUAGS6lbCsuGQCJTAAATInA wIn/3wRBOCX/4QSJpWzAiUxMicD/5AE4QUEAAA7b////5xX/7T3/6in/8F+Q27aJwMDAwKXApWxs pcCliUyQ29ulwMAZLkGJwIn//9tBQTglODgrbIn/+M3/9aRBQS7/84jb25BBLhkuQUH//vqQOmb/ +/RmAGa2/9vb/7YuQTgDAygDA2QlOEEgA3A6A3G229sDA07b/9tMiaUDA1QDAzVAA3AFA2kEBAgr A3EAA2gDA1m225AxA3FyAmk4OCVVA24aA28mA3EOGS4RA2wLA2tGA3ADAy8DA19RA28uOCUZLjhh A20ATEwDAzwEBA9MA28WA27btmZbA26JiUw4QS5siWxMiYmJiaWlpWxspaU6AGZmA2zbkGaQOjpm tttsA2s6OpCQZpA3A3GJwKUZDiU4QThmOpAOJTinQEGQkNuBE1//tra2kDqMIVguGRmHGluhOUc4 LhklOC51Bmc6ZrZmZjrCXijHZCOcMkx7DWKWLFCtRjsAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAABQu09AAAAK2UlEQVR4nM2dz28bxxXHB7oMedAlBx2oCwGedM2hMNqDgB4LG+nB sGVYVVS4hi3IBizLkhE0hn1r7aIJ2gAGEgQBSoaEEEkUJZClWMmiWlWW4P6uU7hwf8BwkCZt+rv/ QOf3zixXMXff15YeLC5nd3bmwze/3ryZXbOclZGMwp6PcMaPGNFL7KUjRrS++ZCcxrAVeyLvX+0z 4GShwckgkiU/KgVBtH7vSVaiA+ioRMvFzDoKUWA64nyFRMQ0SyaIZKIlDtARlIgvVrO2/rwThZWn iiEqE+sRM7UZqCNSqckSyw4BJ4oaGZTofnEjK1EIBiMqL1B1JL5B29oWL2Ul8qhcdQIQlZYeUIhC NAhRo7ZEJ3H1G0FEbWuWBFePVij9kTfA4ogGSnT7iPnjPpmIl9tZiXrRbOWmWWztL5GJeqBIRGu1 7PXIoxgdBVpsxJFWm0fAmr1ZrcpDlplRaB7B7KNCuUnQkf97h/1AX2o5oNQKyxCiYPgnEQ3xQQgO 0GLb2AUAsaCp0YhebqySiZSS5MFS0WbZ9QaASKSuO4FUEAf0kDs1BJDrl+hEFdoMMtE8Ilr+NPtI 1Z2sEM9rvoa2j7odyFwktJBIRDs1auuPjBBMzS7U99jUyMi3pxk79a3rx+WnGEhfF1fujMigFROy J6f8az2TSFrNrnI2Nae+3pgbl0TfZOzyd0Ses2z+dRfNhOzJ+dvjx0OUPGwussfLloixcfPD5Qnx XcJFV2TIHE69edxGTSo0GlG11ZKlNjLrESkSmfmbrmhMyBxuzMlvvm1juQD20QPT+hWMIZqfZZ+v ozumqnkaysN0tLbfOfWHaaMOQ/SBqObsrWlVnYyYUHRyvKdmo+rRxsAAu/zdkZE5/cuvm7rN5EnZ AEWRzkYhe1I0yNshEM4TQRzXmJlBIkeRLZL32E5pkXMRgo68bnEUV2prCzRvjTdlAxHxZpVGFHGB iEqD9xBEMvUIijgXeRlEhPKN8EX6fC028lOJdgsYIL+TJBH9+5//ohLp1GH+oyJiNSve/mk25DJi vubph0z06SdflAeS/yg0kqj2UXu7AtBR6Num6Wh5E+M/kv0RxmLbeIQiYsIIQBD9p7YH4BkGlhpt ls1cDcLZRwOP6TU7mv0jiNYKGB8b0D6qDFFh1JCGK7VFqrfGeJCAlj9xfc02MRxRqbOZncjngtlH 9QZsFQLkrSlvbqf3H82P+FNa8K4xWY/S+o+Ue2Q2NI2A9Sgi6t9/JOSnMqrnNsIRLa3w9P4jUW7X jf/IqSmzWRS3j7rby5F6+vUfxdyQDGof/a/9IL3/6M7tnnQsUmbnthPOt1L7j2R8XcwBTWqIA4g6 R20nS7NJW/GLegCUjgi7D51asB4t3qWv92N1NLjdIhD1sAGIOKfPRbDj2uI6fd+ISh22lv3wY+ru w8h95KBonojSPpVIU8FW/JYGiJY/07MjYOuvY3xswF1jmP2QplNCELUaas8owX/kOY1oVpIh4u0O RD1B1T6sGeRw0Oxh9Wh1h9r6LRhsZ90ieU7LGIPqiL6TRREh5/2LFCKnJiARcV8tfr7GCzSLTXyA iQrUVVHTyHBEjQrVD+lmaiAiXqb7If0hDUFE9x5j92gNLexm2H8UXAvHfTLRQHMn/f6j8JpO3Tf9 SUSVwU56/1F4zSMyqiIRvfrqV9L7j/Qhbt8Me5LFUjJZlbsZ9h951wIK0ErNfnr/UXgtviOCSLTF O+n3H9lrByGRiErU1SyGHvtLG/Qe0m2uhRBxwK567NoR52tkIv8JTTpRawCxTqt7SNC+WtRaNo4I Vmoo+6j9CWiPlt9pE/sjxD62mHeE2NaIT9PDe8i1OkpHqD1aradI/xFwl0Z2/5FhoTiOQvuI8zpE Q8hRZAFBBKzZXYSOGNIzeq+I0JFMHdUfdThx77F1R8B0VKH1kNbih3q0jtqz69375axEARWOiPj8 mnsoE1eP/lul+SEtV95/ZIxWjzYQ+9iQq1kPNyFPZupnRSFW7UqhFvqPmJrczkk/kucjMiFzEHPa pI0jmHWRp59thf4jkeusDvk+IhMyhw+mA/+RWjzyF0dIRAv3h2L+I8fnP+5kQubwy+MxTwSyrTXa 3Zj/6K1fqZD0/kXuBhMyh3n1GbiO1Fo2xD4qlNYj9aiPG7cZ+810dNKJCY0rj1agIxbbNUrS0ePO esx/dPnXykEkZCrwNZqQPPxCKO1nPk3MNUoe12L+oym1k++G2c+n/UcmZA6ymOccCth7TFiFME4s 9DPHQwQi9w060hJW/KJ1WsEEtI/qqHVaFNEC4A0ow1gbch/wVoa4lmhEm10EDXI1i1qzj9I7EJ4T 0RY/ak8e1On7/Htd7CSixfXt7ES9ZACi7Y6yswn7jyIbCWMfLe3Q3w4rJVASra0VMfvYgK3/McDn Hx/aiK0f0Nag4xphpI1MEejTGQWA/ygrBHwUYf6rBnFEe2uUUrNfkW/SKdep/iOHlBoimahFfcLX tjd/+yGtHt3foRH5XCkhkonaTcTTq6YXoKVkZH2vkt5/ZKJ4RHFPJEF6nl/rx3+ko8BZtGz1PL/W h/9IR4msNRPpjWtewlkCSuTaUWr/kY5izSKtKTKRree1dj1ST7/+Iy+KEtv2ITra56X0/qMoCrNd N64u8YHV9P4jE8VKfNovZOZPF6/m83dPq8DJd/J3/3gz72vj5NfVpVvvy4J/OyRaQrxLI66hW9+/ ePLHV9jMD6/oAJv5+Wl5QtG9HRH95CITp68GSNUKYk9EfOIvMpQ0Ol/5Kf4MBGNXhe6iK4LKXVHS hLxD005tb71vikb8ePFv5q/y+62/nY50pIHf+YuCkNoTf1qVVqg7xjWRKzWRszrqCvLaFQMg69H3 Lnq3vKGrmLiSvybqnJ/aFietr1mgUZW4lLunn33H50pznTbvP2Aombkp6Yxa+gwYob89P+Y7UnLy ByqTq6rY+gw4ojV6W4tP+13j9lrUswOOaIH+/mwtMzflzF+XgGxEzP74PgNWWk8+psMMRzI6ekXj qWp+jaUIGOGDgP8VRk9FEkogiyDen626o8QSyCKfPVKrWQT/UaAoUwKBpvoMWPuouAto/VDLttbC tX7Jlq5TTOoha08/JRMFjS1Np5jcQwL6bFVuWTrFxB6S/NQhMxZtlk4xsX2S92e7kS1Lp5jUQ5ZX IU+KA9tacTXRM5p74eKy3nucuIv1EIl4OfFtQ4dI9OUniW9lOESi5sNHyUTnGTsnY06yY2O53Nkv yE8VZK/YRMxJG9OIvsEetISJxWLqNKNSKyZ6j3Nn3xvLnbiUy01cyp3/Ri534pV3xxTDJS9vfdLG tNnoG8x9Bt1EmfRP2pBJ02VdbiQTSflI5CfyPPtnGVBEE04/Wt41v/ijMf+szMfdZ8VEUUQT7FIU 06Tpst6tJvaQKvoxQ/TemM38w38wkdiFr4kYXz0TEcmY7uQEC+6zlKqAJoJS0yGdpldqlW6S/SPj HzMgno5OiNrwuzNxHU0cC1SUO3+uR0cuyvlz8ZgmTWcfVXkxWUeT+tYPz+Qu/N1lfuH36kxINOln cuG3Y+rP3adER7HXwpgmTU9HiaOILgShTHGURTEpQvJnTvjtSp+0Me3P1mVn7jOZmyjmmqlHUUim 6bJeKSfuPsy9cHFZVw/Q0eER7WwfNR1xjvn/RYRpcjP/2o88Azp1wMgg6N3QzN+zRRIgEVlefFV5 hvwfjPo3jQ3/6CsAAAAASUVORK5CYII= ------=_Part_229728_1966990708.1483146437420--