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=HEADER_FROM_DIFFERENT_DOMAINS, HTML_MESSAGE,SPF_PASS,URIBL_BLOCKED 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+deb8u2) with ESMTP id v75KCePV013262 for ; Sat, 5 Aug 2017 22:12:41 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1de5Ml-00042Z-EK for rs_out_1@blacksheep.org; Sat, 05 Aug 2017 21:08:07 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1de5Mi-00042Q-AS for rsgb_lf_group@blacksheep.org; Sat, 05 Aug 2017 21:08:04 +0100 Received: from mout02.posteo.de ([185.67.36.66]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1de5Mc-0000q2-1z for rsgb_lf_group@blacksheep.org; Sat, 05 Aug 2017 21:08:02 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id 96963208F7 for ; Sat, 5 Aug 2017 22:07:56 +0200 (CEST) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3xPvwr1T7Yz1090 for ; Sat, 5 Aug 2017 22:07:56 +0200 (CEST) Message-ID: <5986259C.8020409@posteo.de> Date: Sat, 05 Aug 2017 22:07:56 +0200 From: DK7FC 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: <15db2643c6f-5f13-23c2@webprd-m101.mail.aol.com> In-Reply-To: <15db2643c6f-5f13-23c2@webprd-m101.mail.aol.com> X-Scan-Signature: bb953ecadee360a40f72202c1637b86b Subject: Re: VLF: Carrier on 3675.005 Hz Content-Type: multipart/alternative; boundary="------------080005040701000803020209" 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: 12340 This is a multi-part message in MIME format. --------------080005040701000803020209 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Markus, VLF, The carrier is quite stable now. The QRN has been a bit lower today and yesterday. Maybe the worst days regarding QRN are over now? I'm curious to try sending an EbNaut message but now you made the effort to set up the spectrograms/grabber, so it would be a pity not to use it! So i will continue running the carrier for some time. I'm thinking about making QSY by -312.5 uHz on Monday 0:00 UTC, i.e. in about 26 hours. Would you agree that this makes sense? For coming EbNaut attempts on that 82 km band i would start with 3 characters in 24 hours. Are you interested? And if so, would you like to prepare a SL instance with an FFT length of >= 25 hours (assuming you are creating a txt file each hour)? 73, Stefan Am 05.08.2017 14:35, schrieb Markus Vester: > Yes the signal is definitely making it to Amberg! This is a fine > result of mutual collaboration: Stefan DK7FC erecting the transmit > facility and posing the low frequency challenge, the DL0AO team > (specifically Tom DK1IS and Bernd DF9RB) laying out antennas in a > quiet forest around their club station and installing dedicated > hardware, and myself trying to tame 14 SpecLab instances without > introducing too many errors. > > The first indication of a 3675.005 Hz peak appeared already a couple > of days ago on the E-probe antenna, and is still shown in > the ultra-narrow 9.3 uHz window (waiting to be updated later tonight). > Since yesterday, antenna and GPS connections have been greatly > optimized, and the 31 uHz peak appeared early this morning > after "only" 9 hours of averaging. > > Best 73, > Markus (DF6NM) > > > -----Ursprüngliche Mitteilung----- > Von: DK7FC > An: rsgb_lf_group > Verschickt: Sa, 5. Aug 2017 11:17 > Betreff: Re: VLF: Carrier on 3675.005 Hz > > VLF, > > After nearly 8 days the carrier is still on the air without an > interruption, despite occasional thunderstorms :-) > It looks like the SNR is suffering by summer QRN, as expected. > > The stable carrier was good for doing local tests with my > Raspi+Octo-soundcard. The system is now completely configured > including system time setting via the GPS module. I recorded a few > days from the carrier, converted the data files into wav, reprocessed > them in SpecLab: The carrier is stable and on the expected frequency, > so the sample rate correction via vlfrx tools seems to work. > > Forthermore i corrected some bugs in the circuit of my portable RX > loop preamp for VLF (must have been late in the night when i built it > up a few months ago). Now the noise is much lower. It looks promising! > So it is time for a portable VLF experiment in the far field, just to > check the system more seriously. > > The crew of DL0AO has built up and optimised their VLF system to > receive the weak 3675.005 Hz carrier in abt 220 km distance. Looks > like there is something on their cardioidal spectrogram pointing to West, > http://df6nm.bplaced.net/dl0ao/VLFgrabber/vlfgrabber_dl0ao_test.htm > Something like 10 dB SNR in 31 uHz. That's not so bad! > > I will run it for some more time until the trace is a bit longer. Then > in some days i like to start transmitting an EbNaut message on that > frequency which can be stacked until a decode appears. Markus has > developed a tool for windows to do the stacking, maybe it works in > that experiment... It will also be a test to see if i can decode the > message from my own recording using vlfrx tools, an important step to > pass... > > So far so good. What are YOUR projects you are currently working on, > LF/MF/VLF related? > > 73, Stefan > > > Am 28.07.2017 16:56, schrieb DK7FC: > > Hi VLF, > > I'm back from LF for a while and built up my large VLF coil which > was used on 2970 Hz in the beginning of the year. Actually it is > under maintenance, one of the six stacks has to be replaced. It is > already dismantled but the new wire is not yet wound on the 250 mm > diameter PVC tube again. > So now the resonance is higher! I didn't know where it is and just > connected the coil and scanned the frequency downwards. Near 3685 > Hz i found a maximum of the antenna. Since the Q is not extremely > high, i decided to tune to 3675 Hz and added the usual 5 mHz > offset, to stay away from multiples of 1 Hz. > > So, now *since 14:40 UTC* a carrier is running on *3675.005 Hz*. > The antenna current is *170 mA*. I estimate the *ERP is just 3 uW*! > > I guess this is a first amateur radio transmission on the *82 km* > band and that class of ERP (?). > > Hopefully the coil will hold the *15.5 kV* with just 5 stacks of > windings. It's inductance is *3.9 H* in the moment! > > I intend to run the carrier for at least a few days, depending on > the feedback. > > Good luck for the VLF experts! > > 73, Stefan > > PS: A 424 uHz RDF spectrogram is running at > http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html > (First pixel appears in 30 minutes) > --------------080005040701000803020209 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Markus, VLF,

The carrier is quite stable now. The QRN has been a bit lower today and yesterday. Maybe the worst days regarding QRN are over now?
I'm curious to try sending an EbNaut message but now you made the effort to set up the spectrograms/grabber, so it would be a pity not to use it! So i will continue running the carrier for some time.
I'm thinking about making QSY by -312.5 uHz on Monday 0:00 UTC, i.e. in about 26 hours. Would you agree that this makes sense?

For coming EbNaut attempts on that 82 km band i would start with 3 characters in 24 hours. Are you interested? And if so, would you like to prepare a SL instance with an FFT length of >= 25 hours (assuming you are creating a txt file each hour)?

73, Stefan

Am 05.08.2017 14:35, schrieb Markus Vester:
Yes the signal is definitely making it to Amberg! This is a fine result of mutual collaboration: Stefan DK7FC erecting the transmit facility and posing the low frequency challenge, the DL0AO team (specifically Tom DK1IS and Bernd DF9RB) laying out antennas in a quiet forest around their club station and installing dedicated hardware, and myself trying to tame 14 SpecLab instances without introducing too many errors.

The first indication of a 3675.005 Hz peak appeared already a couple of days ago on the E-probe antenna, and is still shown in the ultra-narrow 9.3 uHz window (waiting to be updated later tonight). Since yesterday, antenna and GPS connections have been greatly optimized, and the 31 uHz peak appeared early this morning after "only" 9 hours of averaging.

Best 73,
Markus (DF6NM)


-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Sa, 5. Aug 2017 11:17
Betreff: Re: VLF: Carrier on 3675.005 Hz

VLF,

After nearly 8 days the carrier is still on the air without an interruption, despite occasional thunderstorms :-)
It looks like the SNR is suffering by summer QRN, as expected.

The stable carrier was good for doing local tests with my Raspi+Octo-soundcard. The system is now completely configured including system time setting via the GPS module. I recorded a few days from the carrier, converted the data files into wav, reprocessed them in SpecLab: The carrier is stable and on the expected frequency, so the sample rate correction via vlfrx tools seems to work.

Forthermore i corrected some bugs in the circuit of my portable RX loop preamp for VLF (must have been late in the night when i built it up a few months ago). Now the noise is much lower. It looks promising! So it is time for a portable VLF experiment in the far field, just to check the system more seriously.

The crew of DL0AO has built up and optimised their VLF system to receive the weak 3675.005 Hz carrier in abt 220 km distance. Looks like there is something on their cardioidal spectrogram pointing to West,
http://df6nm.bplaced.net/dl0ao/VLFgrabber/vlfgrabber_dl0ao_test.htm
Something like 10 dB SNR in 31 uHz. That's not so bad!

I will run it for some more time until the trace is a bit longer. Then in some days i like to start transmitting an EbNaut message on that frequency which can be stacked until a decode appears. Markus has developed a tool for windows to do the stacking, maybe it works in that experiment... It will also be a test to see if i can decode the message from my own recording using vlfrx tools, an important step to pass...

So far so good. What are YOUR projects you are currently working on, LF/MF/VLF related?

73, Stefan


Am 28.07.2017 16:56, schrieb DK7FC:
Hi VLF,

I'm back from LF for a while and built up my large VLF coil which was used on 2970 Hz in the beginning of the year. Actually it is under maintenance, one of the six stacks has to be replaced. It is already dismantled but the new wire is not yet wound on the 250 mm diameter PVC tube again.
So now the resonance is higher! I didn't know where it is and just connected the coil and scanned the frequency downwards. Near 3685 Hz i found a maximum of the antenna. Since the Q is not extremely high, i decided to tune to 3675 Hz and added the usual 5 mHz offset, to stay away from multiples of 1 Hz.

So, now since 14:40 UTC a carrier is running on 3675.005 Hz. The antenna current is 170 mA. I estimate the ERP is just 3 uW!

I guess this is a first amateur radio transmission on the 82 km band and that class of ERP (?).

Hopefully the coil will hold the 15.5 kV with just 5 stacks of windings. It's inductance is 3.9 H in the moment!

I intend to run the carrier for at least a few days, depending on the feedback.

Good luck for the VLF experts!

73, Stefan

PS: A 424 uHz RDF spectrogram is running at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html (First pixel appears in 30 minutes)

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