Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,SPF_PASS, T_DKIM_INVALID,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; 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+deb8u2) with ESMTP id v7EANkZI016677 for ; Mon, 14 Aug 2017 12:23:47 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1dhCSW-0003r4-MZ for rs_out_1@blacksheep.org; Mon, 14 Aug 2017 11:18:56 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1dhCSV-0003qv-Jb for rsgb_lf_group@blacksheep.org; Mon, 14 Aug 2017 11:18:55 +0100 Received: from omr-a016e.mx.aol.com ([204.29.186.65]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.89) (envelope-from ) id 1dhCSR-0003dN-OR for rsgb_lf_group@blacksheep.org; Mon, 14 Aug 2017 11:18:54 +0100 Received: from mtaomg-aao01.mx.aol.com (mtaomg-aao01.mx.aol.com [172.27.21.15]) by omr-a016e.mx.aol.com (Outbound Mail Relay) with ESMTP id 2BCDC380008C for ; Mon, 14 Aug 2017 06:18:49 -0400 (EDT) Received: from core-acb02c.mail.aol.com (core-acb02.mail.aol.com [172.27.24.2]) by mtaomg-aao01.mx.aol.com (OMAG/Core Interface) with ESMTP id DB5D438000082 for ; Mon, 14 Aug 2017 06:18:48 -0400 (EDT) Received: from 80.146.228.87 by webprd-a24.mail.aol.com (10.72.50.205) with HTTP (WebMailUI); Mon, 14 Aug 2017 06:18:48 -0400 Date: Mon, 14 Aug 2017 06:18:48 -0400 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <15de040c94a-5486-165b5@webprd-a24.mail.aol.com> In-Reply-To: <028c01d31479$c98102f0$5c8308d0$@comcast.net> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [80.146.228.87] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1502705929; bh=/rXBcmnkmSKErAIGRwr6+3mceWUrIEe4g+mhfbOaSs0=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=6nU/lFYV1jor8U1WhHC3B+oLMLcQzN0CNevcF8TfWnus1pkF8SpfjNR67q/t0x2xK 9xNH1DAR/y4UGiTGS8ithXT6wm+ZhMmJz+7IWwegShl3tx9dMN8/tMV/2lVRBk4ET/ 30n29K01fX8JBytrchodTifTJ/5O0HJgDQ4R7j+Q= x-aol-sid: 3039ac1b150f599179084967 X-Scan-Signature: 96e7ff1ec9673d9aa57a617c94da6cf3 Subject: Re: VLF: Carrier on 3675.005 Hz - fieldstrength Content-Type: multipart/alternative; boundary="----=_Part_110411_1883873754.1502705928519" 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: RO X-Status: X-Keywords: X-UID: 12384 ------=_Part_110411_1883873754.1502705928519 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Comparing Stefan's carrier peak (-135 dB on the W cardioid) to my own 8270 = Hz transmission from Aug 5 (-119 dB) shows a ~ 16 dB difference (assuming f= lat frequency response from the antennas). The distances are 226 km and 48 = km, accounting for 13.5 dB using 1/r. Stefan's estimated ERP on 3675 is abo= ut 8 dB less than mine on 8270. So we can conclude that propagation from St= efan had about 13.5 + 8 - 16 =3D +5.5 dB propagation gain over 1/r groundwa= ve. In other words, the fieldstrength has been approximately doubled by the= presence of the ionosphere. To me this is somewhat unexpected, as a simple geometric calculation for re= flection at 70 km ionospheric height gives 41 km path difference, i.e. perf= ect antiphase at this wavelength and distance. It will be interesting to look at simulation results. All the best, Markus (DF6NM)=20 -----Urspr=C3=BCngliche Mitteilung-----=20 Von: hvanesce An: rsgb_lf_group Verschickt: So, 13. Aug 2017 23:20 Betreff: RE: VLF: Carrier on 3675.005 Hz / EbNaut - YES again #AOLMsgPart_2_4264e2f7-b10f-4b5e-afea-c65ee78e6826 td{color: black;} @font-= face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;}@font-face {font-= family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;}.aolReplacedBody p.aolmail_Ms= oNormal,.aolReplacedBody li.aolmail_MsoNormal,.aolReplacedBody div.aolmail_= MsoNormal {margin:0in; margin-bottom:.0001pt; font-size:12.0pt; font-family= :"Times New Roman","serif";}.aolReplacedBody a:link,.aolReplacedBody span.a= olmail_MsoHyperlink {mso-style-priority:99; color:blue; text-decoration:und= erline;}.aolReplacedBody a:visited,.aolReplacedBody span.aolmail_MsoHyperli= nkFollowed {mso-style-priority:99; color:purple; text-decoration:underline;= }.aolReplacedBody p.aolmail_aolmailmsonormal,.aolReplacedBody li.aolmail_ao= lmailmsonormal,.aolReplacedBody div.aolmail_aolmailmsonormal {mso-style-nam= e:aolmail_msonormal; mso-margin-top-alt:auto; margin-right:0in; mso-margin-= bottom-alt:auto; margin-left:0in; font-size:12.0pt; font-family:"Times New = Roman","serif";}.aolReplacedBody p.aolmail_aolmailmsochpdefault,.aolReplace= dBody li.aolmail_aolmailmsochpdefault,.aolReplacedBody div.aolmail_aolmailm= sochpdefault {mso-style-name:aolmail_msochpdefault; mso-margin-top-alt:auto= ; margin-right:0in; mso-margin-bottom-alt:auto; margin-left:0in; font-size:= 12.0pt; font-family:"Times New Roman","serif";}.aolReplacedBody span.aolmai= l_aolmailmsohyperlink {mso-style-name:aolmail_msohyperlink;}.aolReplacedBod= y span.aolmail_aolmailmsohyperlinkfollowed {mso-style-name:aolmail_msohyper= linkfollowed;}.aolReplacedBody span.aolmail_aolmailemailstyle17 {mso-style-= name:aolmail_emailstyle17;}.aolReplacedBody p.aolmail_aolmailmsonormal1,.ao= lReplacedBody li.aolmail_aolmailmsonormal1,.aolReplacedBody div.aolmail_aol= mailmsonormal1 {mso-style-name:aolmail_msonormal1; margin:0in; margin-botto= m:.0001pt; font-size:12.0pt; font-family:"Times New Roman","serif"; color:b= lack;}.aolReplacedBody span.aolmail_aolmailmsohyperlink1 {mso-style-name:ao= lmail_msohyperlink1; mso-style-priority:99; color:blue; text-decoration:und= erline;}.aolReplacedBody span.aolmail_aolmailmsohyperlinkfollowed1 {mso-sty= le-name:aolmail_msohyperlinkfollowed1; mso-style-priority:99; color:purple;= text-decoration:underline;}.aolReplacedBody span.aolmail_EmailStyle25 {mso= -style-type:personal; font-family:"Calibri","sans-serif"; color:#1F497D;}.a= olReplacedBody span.aolmail_EmailStyle26 {mso-style-type:personal-reply; fo= nt-family:"Calibri","sans-serif"; color:#1F497D;}.aolReplacedBody .aolmail_= MsoChpDefault {mso-style-type:export-only; font-family:"Calibri","sans-seri= f";}@page WordSection1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in;}= .aolReplacedBody div.aolmail_WordSection1 {page:WordSection1;} Markus and Stefan, =20 Along with the FDTD diurnal phase simulation, I=E2=80=99ll include diurnal = amplitude for comparison to the prospective path loss calculation that Mark= us mentioned.=20 =20 73, =20 Jim AA5BW =20 =20 From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacks= heep.org] On Behalf Of Markus Vester Sent: Sunday, August 13, 2017 4:49 PM To: rsgb_lf_group@blacksheep.org Subject: Re: VLF: Carrier on 3675.005 Hz / EbNaut - YES again =20 Hi Stefan, despite the 27% loss of signal, the message was decoded fine, ev= en with a couple of dB to spare - not bad at all! Hope you can repair your = coil and get back on air soon. Jim, some simulation for the 226 km path might indeed be helpful. I suspect= that the path difference between groundwave and first-hop skywave is close= to a half-wavelength, possibly leading to partial cancellation and stronge= r diurnal variability. However the carrier SNR has not been strong enough t= o make a decently resolved measurement of diurnal amplitude and phase varia= tions. We could try to obtain a coarse estimate of absolute fieldstrength, using t= he received carrier level and e.g. DHO38 for reference. Knowing Stefan's ra= diated power, we could then try to derive propagation attenuation.=20 Best 73, Markus (DF6NM) -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: So, 13. Aug 2017 22:20 Betreff: Re: VLF: Carrier on 3675.005 Hz / EbNaut - YES Hi VLF,=20 The repetition of yesterdays message failed. At 15:38 UTC the safety functi= on tripped. I've just been on the roof, when re-starting the transmission i= can see a spark in the center of one of the stacks. So now there is anothe= r one which has a flash over! :-( It must be replaced, which is a lot of work. So the tranmissions on 3675 Hz= will stopp for some time. At least we have some carrier detections and eve= n EbNaut decodes. I need to think about a different coil concept.... More current, more volta= ge, more power, more more more! Am 13.08.2017 16:57, schrieb hvanesce@comcast.net:=20 Stephan wrote: =E2=80=9CThe phase of that best decode is quite varying=E2=80=9D Is that observation based on the attached EbNaut Decoder window image from = Markus? It is just based on that decoder data. It is not really proof, just an idea= . Would it help to have an FDTD diurnal phase plot for this path at 3575Hz? For sure it would be interesting! If you like, do it. I would be curious to= see it. 73, Stefan ------=_Part_110411_1883873754.1502705928519 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Comparing Stefan's carrier peak (-135 dB on the W cardio= id) to my own 8270 Hz transmission from Aug 5 (-119 dB) show= s a ~ 16 dB difference (assuming flat frequency response from the= antennas). The distances are 226 km and 48 km, accounting for 13= .5 dB using 1/r. Stefan's estimated ERP on 3675 is about 8 d= B less than mine on 8270. So we can conclude that propagation from Stefan&n= bsp;had about 13.5 + 8 - 16 =3D +5.5 dB propagation gain over 1/r grou= ndwave. In other words, the fieldstrength has been approximately doubl= ed by the presence of the ionosphere.

To me this is somewhat unexpec= ted, as a simple geometric calculation for reflection at 70 km io= nospheric height gives 41 km path difference, i.e. perfect antiphase a= t this wavelength and distance.

It will be interesting to look at si= mulation results.

All the best,
Markus (DF6NM) 

-----= Urspr=C3=BCngliche Mitteilung-----
Von: hvanesce <hvanesce@comcast.n= et>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschi= ckt: So, 13. Aug 2017 23:20
Betreff: RE: VLF: Carrier on 3675.005 Hz / E= bNaut - YES again

Markus and Stefan,

 

Along with the FDTD diurnal phase simulation, I=E2=80=99ll include= diurnal amplitude for comparison to the prospective path loss calculation = that Markus mentioned.

 

73,

 <= /span>

Jim AA5BW

 

<= p class=3D"aolmail_MsoNormal"> 

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] O= n Behalf Of Markus Vester
Sent: Sunday, August 13, 2017 4:49 = PM
To: rsgb_lf_gr= oup@blacksheep.org
Subject: Re: VLF: Carrier on 3675.005 Hz /= EbNaut - YES again

 

= Hi Stefan, despite the 27% loss of signal, the message was decoded fine, ev= en with a couple of dB to spare - not bad at all! Hope you can repair = your coil and get back on air soon.

Jim, some simulation for the 226= km path might indeed be helpful. I suspect that the path difference betwee= n groundwave and first-hop skywave is close to a half-wavelength, poss= ibly leading to partial cancellation and stronger diurnal variability. Howe= ver the carrier SNR has not been strong enough to make a decently= resolved measurement of diurnal amplitude and phase variations.
We could try to obtain a coarse estimate of absolute fieldstrength, = using the received carrier level and e.g. DHO38 for reference. Kn= owing Stefan's radiated power, we could then try to derive propag= ation attenuation.

Best 73,
Markus (DF6NM)



-----U= rspr=C3=BCngliche Mitteilung-----
Von: DK7FC <selberden= ken@posteo.de>
An: rsgb_lf_group <rsgb_lf_g= roup@blacksheep.org>
Verschickt: So, 13. Aug 2017 22:20
Betref= f: Re: VLF: Carrier on 3675.005 Hz / EbNaut - YES

Hi VLF,

The repetition of yesterdays= message failed. At 15:38 UTC the safety function tripped. I've just been o= n the roof, when re-starting the transmission i can see a spark in the cent= er of one of the stacks. So now there is another one which has a flash over= ! :-(
It must be replaced, which is a lot of work. So the tranmissions o= n 3675 Hz will stopp for some time. At least we have some carrier detection= s and even EbNaut decodes.

I need to think about a different coil co= ncept.... More current, more voltage, more power, more more more!

Am= 13.08.2017 16:57, schrieb hvanesce@comcast.net:

Stephan wr= ote:

=E2=80=9CThe phase of that best decode is quite v= arying=E2=80=9D

Is that observation based on the attached EbNaut Decoder window im= age from Markus?

It is just based on that decoder data. It is not really proof, ju= st an idea.

Would it help to have an FDTD diurnal phase plot for this= path at 3575Hz?

For sure it would be interesting! If you like, do it. I would be = curious to see it.

73, Stefan

------=_Part_110411_1883873754.1502705928519--