Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id v96AxHrD010914 for ; Fri, 6 Oct 2017 12:59:18 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1e0QGn-0001J8-Lu for rs_out_1@blacksheep.org; Fri, 06 Oct 2017 11:54:17 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1e0QGm-0001Iz-Vl for rsgb_lf_group@blacksheep.org; Fri, 06 Oct 2017 11:54:16 +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 1e0QGj-0006Mp-Mk for rsgb_lf_group@blacksheep.org; Fri, 06 Oct 2017 11:54:15 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id 40912209A7 for ; Fri, 6 Oct 2017 12:54:11 +0200 (CEST) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3y7mjH03dHz1092 for ; Fri, 6 Oct 2017 12:54:10 +0200 (CEST) Message-ID: <59D760D2.9010700@posteo.de> Date: Fri, 06 Oct 2017 12:54:10 +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: <15ef120d4f7-c0e-1b445@webjas-vab076.srv.aolmail.net> In-Reply-To: <15ef120d4f7-c0e-1b445@webjas-vab076.srv.aolmail.net> X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hello Markus, I saw that the night time SNR was much worse than day time SNR. But i would expect that it should work anyway with just 1 character. Maybe there is an error somewhere in the recording or so? Or maybe the phase is doing strange things during the night! [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: bf14357d5ee2e4a717b88d90ab36122c Subject: Re: VLF: 300 mA on 6470 Hz - 1 char decoded at DF6NM Content-Type: multipart/alternative; boundary="------------060609000705030500090702" 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_20_30,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 This is a multi-part message in MIME format. --------------060609000705030500090702 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hello Markus, I saw that the night time SNR was much worse than day time SNR. But i would expect that it should work anyway with just 1 character. Maybe there is an error somewhere in the recording or so? Or maybe the phase is doing strange things during the night! I can send you a 2 character message this afternoon. But 16 UTC the next 16 character message starts. So let's try *f = 6470.005000 Hz Start time: 06.October.2017 11:00:00 UTC Symbol period: 20 s Characters: 2 CRC bits: 8 Coding 16K21A Duration: 3h33min20sec Antenna current: 300 mA* 73, Stefan Am 06.10.2017 12:00, schrieb Markus Vester: > Despite truncated data from a 31 uHz instance and severe railroad QRM, > I happened to get a correct constant-phase decode from my home antenna. > > Best 73, > Markus > > > -----Ursprüngliche Mitteilung----- > Von: Markus Vester > An: rsgb_lf_group > Verschickt: Fr, 6. Okt 2017 11:00 > Betreff: Re: VLF: 300 mA on 6470 Hz - 1 char not decoded at DL0AO > > Unfortunately the 1-character message was not decoded correctly from > DL0AO data. The prior carrier had been well visible during the day, > but completely drowned in nighttime QRN. Would you perhaps like to try > another short EbNaut message in daylight? > Best 73, > Markus > > > > -----Ursprüngliche Mitteilung----- > Von: DK7FC > > An: rsgb_lf_group > > Verschickt: Mi, 4. Okt 2017 11:52 > Betreff: Re: VLF: 300 mA on 6470 Hz > > Hi Paul, > > Am 04.10.2017 11:07, schrieb Paul Nicholson: > > You may as well use 8K19A or even 4K15A. > > If you look at the big table at the end of > > http://abelian.org/ebnaut/ops.shtml > > you can see there's no further improvement in success > rate for 6 bit payloads (1 char plus zero CRC = 6 bits). > > The reason appears to be the payload is simply not long > enough to make full use of the longer constraint lengths. > > > OK, so i'm changing to: > > *f = 6470.005000 Hz > Start time: 04.October.2017 17:00:00 UTC > Symbol period: 240 s > Characters: 1 > CRC bits: 0 > Coding 8K19A > Duration: 12h48min > Antenna current: 300 mA* > > > For some reason, the signal last night was about 6dB weaker. > > Interesting. And for some reason, the signal was much stronger last > night at SQ5BPF. Did you see it? What could be the reason? Just the > noise blanker / background QRN? > The message will give you/us and 3rd impression about SNR and phase. A > 10 deg phase variation between last night and the night before seems > already to be quite high, relative to what we observed at 8270. Maybe > we will learn a bit about propagation by that. > The 1 char message is for Jacek mainly. The chance for a decode will > be high i think. Then i thought i try another (daily) 12 char message > for Jacek before we can try the 100 char message. We've already done > quite much on that 46 km band, so i wouldn't spend to much time there, > 2 weeks maybe. Then QSY to 58 km where we can stretch the record list > a bit by transferring 100 chars to you Paul. > > 73, Stefan > > --------------060609000705030500090702 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Markus,

I saw that the night time SNR was much worse than day time SNR. But i would expect that it should work anyway with just 1 character. Maybe there is an error somewhere in the recording or so? Or maybe the phase is doing strange things during the night!

I can send you a 2 character message this afternoon. But 16 UTC the next 16 character message starts. So let's try
f = 6470.005000 Hz
Start time: 06.October.2017  11:00:00 UTC
Symbol period: 20 s
Characters: 2
CRC bits: 8
Coding 16K21A
Duration: 3h33min20sec
Antenna current: 300 mA

73, Stefan

Am 06.10.2017 12:00, schrieb Markus Vester:
Despite truncated data from a 31 uHz instance and severe railroad QRM, I happened to get a correct constant-phase decode from my home antenna.

Best 73,
Markus


-----Ursprüngliche Mitteilung-----
Von: Markus Vester <markusvester@aol.com>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Fr, 6. Okt 2017 11:00
Betreff: Re: VLF: 300 mA on 6470 Hz - 1 char not decoded at DL0AO

Unfortunately the 1-character message was not decoded correctly from DL0AO data. The prior carrier had been well visible during the day, but completely drowned in nighttime QRN. Would you perhaps like to try another short EbNaut message in daylight?
Best 73,
Markus



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Mi, 4. Okt 2017 11:52
Betreff: Re: VLF: 300 mA on 6470 Hz

Hi Paul,

Am 04.10.2017 11:07, schrieb Paul Nicholson:
You may as well use 8K19A or even 4K15A.

If you look at the big table at the end of

 http://abelian.org/ebnaut/ops.shtml

you can see there's no further improvement in success
rate for 6 bit payloads (1 char plus zero CRC = 6 bits).

The reason appears to be the payload is simply not long
enough to make full use of the longer constraint lengths.

OK, so i'm changing to:

f = 6470.005000 Hz
Start time: 04.October.2017  17:00:00 UTC
Symbol period: 240 s
Characters: 1
CRC bits: 0
Coding 8K19A
Duration: 12h48min
Antenna current: 300 mA


For some reason, the signal last night was about 6dB weaker.
Interesting. And for some reason, the signal was much stronger last night at SQ5BPF. Did you see it? What could be the reason? Just the noise blanker / background QRN?
The message will give you/us and 3rd impression about SNR and phase. A 10 deg phase variation between last night and the night before seems already to be quite high, relative to what we observed at 8270. Maybe we will learn a bit about propagation by that.
The 1 char message is for Jacek mainly. The chance for a decode will be high i think. Then i thought i try another (daily) 12 char message for Jacek before we can try the 100 char message. We've already done quite much on that 46 km band, so i wouldn't spend to much time there, 2 weeks maybe. Then QSY to 58 km where we can stretch the record list a bit by transferring 100 chars to you Paul.

73, Stefan


--------------060609000705030500090702--