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: EATSERVER: mailn 1166; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mailn.lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id uB8AentE021902 for ; Thu, 8 Dec 2016 11:40:50 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1cEvzT-0005Lm-As for rs_out_1@blacksheep.org; Thu, 08 Dec 2016 10:31:51 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1cEvzS-0005Ld-HF for rsgb_lf_group@blacksheep.org; Thu, 08 Dec 2016 10:31:50 +0000 Received: from omr-m013e.mx.aol.com ([204.29.186.14]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.87) (envelope-from ) id 1cEvzO-000611-Dg for rsgb_lf_group@blacksheep.org; Thu, 08 Dec 2016 10:31:49 +0000 Received: from mtaomg-aad01.mx.aol.com (mtaomg-aad01.mx.aol.com [172.26.127.227]) by omr-m013e.mx.aol.com (Outbound Mail Relay) with ESMTP id 4105238000A3 for ; Thu, 8 Dec 2016 05:31:44 -0500 (EST) Received: from core-acb05b.mail.aol.com (core-acb05.mail.aol.com [172.27.24.5]) by mtaomg-aad01.mx.aol.com (OMAG/Core Interface) with ESMTP id EBD6A38000088 for ; Thu, 8 Dec 2016 05:31:43 -0500 (EST) Received: from 80.146.228.78 by webprd-a47.mail.aol.com (10.72.57.69) with HTTP (WebMailUI); Thu, 08 Dec 2016 05:31:43 -0500 Date: Thu, 8 Dec 2016 05:31:43 -0500 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <158ddfd1f0b-5980-42e@webprd-a47.mail.aol.com> In-Reply-To: <58489D36.3080501@posteo.de> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [80.146.228.78] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1481193104; bh=Vnvsd6UhrTQgPpKWLRgKR1uij2zLH4GIpcX+996pUK8=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=LFfDckw7SOS0EzHguqaRI0B/e8WDeXzQpe94AS14ZmxBC67DJlYgExjtvZedyg/x8 YN0szQLqfY9YaX0BukmExVcCdmRzWiySEFVR86qdgnXyzyYkwW9zHS6jY3GyDCufpL SqBU0t9x4Co3L/W7CYSsz5dY0WYZFedZrJkQMWhs= x-aol-sid: 3039ac1a7fe35849368f5136 X-Scan-Signature: b707651713bcd4ad9db4bb0f5d794041 Subject: Re: ULF: Finally 100 mA on 2.97 kHz Content-Type: multipart/alternative; boundary="----=_Part_1225_2009333427.1481193103112" 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: 9743 ------=_Part_1225_2009333427.1481193103112 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Stefan, >> I'm plotting the signal level and noise level, visible on the grabber.= =20 At night, the signal becomes about 10 dB stronger while the noise=20 increases maybe 3 dB. The antenna current is super stable however. What=20 could the reason be? Propagation? I wouldn't assume that. I do not see this effect on 6470 Hz. This is really strange. There even seems to be something like a pre-sunrise= dip before 6 UT. Maybe there is some resonance effect between the ionosphe= re and ground. But at this small TX-RX range, any reflection would need to = be from a high angle, and it is hard to see how that could be excited by yo= ur electric transmit antenna. =20 Best 73, Markus -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: Do, 8 Dez 2016 12:42 am Betreff: Re: ULF: Finally 100 mA on 2.97 kHz Hi Paul, Am 07.12.2016 14:50, schrieb Paul Nicholson: > > About 1uW should give some hint in a hour and very significant > peak on an 8 hour spectrum. I run a constant carrier from 13:30...7:00 UTC. On 7 UTC i will start an=20 EbNaut transmission for my local test: 5 chars 8K19A 80s. This takes=20 half a day about... I also added a few plots and spectrograms to follow the transmission=20 from the tree=20 http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html Also you can check the antenna current plot to get some more=20 information: http://www.iup.uni-heidelberg.de/schaefer_vlf/VLF/TX.png BTW i put 5x 7 Ah accus there and am recording at 24 kS/s stereo to a 32=20 GB USB stick. The recording hast started about 15 UTC and i will drive=20 there (a trip of 2x 110 km!) again sunday morning to bring it back. Poor=20 accus, have to do that job below 0 C. So i have more than 3 day time to run various transmission tests.. I'm plotting the signal level and noise level, visible on the grabber.=20 At night, the signal becomes about 10 dB stronger while the noise=20 increases maybe 3 dB. The antenna current is super stable however. What=20 could the reason be? Propagation? I wouldn't assume that. I do not see this effect on 6470 Hz. Update from 23:20 UTC: I found that the time server program has crashed!=20 :-( And it is an old PC so there are glitches from time to time.=20 Probably this is another reason why you don't see the faintest signal=20 :-( My grabber plots look quite good anyway, so maybe the problem hasn't=20 been so dramatic. Now i'm watching the phase! And since 23:23 UTC it should be stable.=20 This may also explain the lower SNR in daylight, maybe it just has to do=20 with the number of phase jumps in one FFT :-( A few things don't run as unproblematic as i would like but at least a=20 signal is on the air... I will sort out all problems by time... > > You made a long transmission with 30mA, from 2016-06-26_13:00 > to 2016-07-31_08:00, 34.79 days. No trace of the signal even > with a coherent daily stacking gain of 15.4dB. Wait 58 says > 0.036 fT for your ~100nW, which should have been visible in > one day, say 8 hours. > > So something is not adding up. Maybe ERP is much lower > than estimated, or the propagation near the mode 2 cut-off > frequency is more attenuated or suffering a variable phase > due to dispersion. We will find that out! That's the interesting thing on this new land.=20 And i can rise the power by another 8 dB. But later... 73, Stefan ------=_Part_1225_2009333427.1481193103112 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Hi Stefan,

>> I'm plotting the signal level= and noise level, visible on the grabber.
At night, the signal becomes = about 10 dB stronger while the noise
increases maybe 3 dB. The antenna = current is super stable however. What
could the reason be? Propagation?= I wouldn't assume that.
I do not see this effect on 6470 Hz.

Thi= s is really strange. There even seems to be something like a pre-sunrise di= p before 6 UT. Maybe there is some resonance effect between the ionosphere = and ground. But at this small TX-RX range, any reflection would need t= o be from a high angle, and it is hard to see how that could be e= xcited by your electric transmit antenna.
 
Best 73,Markus

-----Urspr=C3=BCngliche Mitteilung-----
Von: DK7FC <= selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blackshee= p.org>
Verschickt: Do, 8 Dez 2016 12:42 am
Betreff: Re: ULF: Final= ly 100 mA on 2.97 kHz

Hi Paul,

Am 07.12.2016 14:50, sch= rieb Paul Nicholson:
>
> About 1uW should give some hint in a h= our and very significant
> peak on an 8 hour spectrum.
I run a con= stant carrier from 13:30...7:00 UTC. On 7 UTC i will start an
EbNaut tr= ansmission for my local test: 5 chars 8K19A 80s. This takes
half a day = about...
I also added a few plots and spectrograms to follow the transmi= ssion
from the tree
http://www.iup.uni-hei= delberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html
Also you can check t= he antenna current plot to get some more
information: http:= //www.iup.uni-heidelberg.de/schaefer_vlf/VLF/TX.png

BTW i put 5x= 7 Ah accus there and am recording at 24 kS/s stereo to a 32
GB USB sti= ck. The recording hast started about 15 UTC and i will drive
there (a t= rip of 2x 110 km!) again sunday morning to bring it back. Poor
accus, h= ave to do that job below 0 C.
So i have more than 3 day time to run vari= ous transmission tests..

I'm plotting the signal level and noise lev= el, visible on the grabber.
At night, the signal becomes about 10 dB st= ronger while the noise
increases maybe 3 dB. The antenna current is sup= er stable however. What
could the reason be? Propagation? I wouldn't as= sume that.
I do not see this effect on 6470 Hz.

Update from 23:20= UTC: I found that the time server program has crashed!
:-( And it is a= n old PC so there are glitches from time to time.
Probably this is anot= her reason why you don't see the faintest signal
:-( My grabber plots l= ook quite good anyway, so maybe the problem hasn't
been so dramatic.Now i'm watching the phase! And since 23:23 UTC it should be stable.
T= his may also explain the lower SNR in daylight, maybe it just has to do with the number of phase jumps in one FFT :-(
A few things don't run as= unproblematic as i would like but at least a
signal is on the air... I= will sort out all problems by time...

>
> You made a long = transmission with 30mA, from 2016-06-26_13:00
> to 2016-07-31_08:00, = 34.79 days. No trace of the signal even
> with a coherent daily stac= king gain of 15.4dB. Wait 58 says
> 0.036 fT for your ~100nW, which = should have been visible in
> one day, say 8 hours.
>
> S= o something is not adding up. Maybe ERP is much lower
> than estima= ted, or the propagation near the mode 2 cut-off
> frequency is more a= ttenuated or suffering a variable phase
> due to dispersion.
We wi= ll find that out! That's the interesting thing on this new land.
And i = can rise the power by another 8 dB. But later...

73, Stefan

<= /div> ------=_Part_1225_2009333427.1481193103112--