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=AC_DIV_BONANZA, 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: INFN-TO: mailn 1233; Body=3 Fuz1=3 Fuz2=3 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 v5JFpM4e004154 for ; Mon, 19 Jun 2017 17:51:23 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1dMysk-0003V5-Ff for rs_out_1@blacksheep.org; Mon, 19 Jun 2017 16:46:26 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1dMysg-0003Uw-Kf for rsgb_lf_group@blacksheep.org; Mon, 19 Jun 2017 16:46:22 +0100 Received: from omr-m015e.mx.aol.com ([204.29.186.15]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.89) (envelope-from ) id 1dMysc-0008Oq-0d for rsgb_lf_group@blacksheep.org; Mon, 19 Jun 2017 16:46:21 +0100 Received: from mtaomg-aah02.mx.aol.com (mtaomg-aah02.mx.aol.com [172.27.1.144]) by omr-m015e.mx.aol.com (Outbound Mail Relay) with ESMTP id 727DD3800046 for ; Mon, 19 Jun 2017 11:46:15 -0400 (EDT) Received: from core-acc03b.mail.aol.com (core-acc03.mail.aol.com [172.26.125.13]) by mtaomg-aah02.mx.aol.com (OMAG/Core Interface) with ESMTP id D76BE38000085 for ; Mon, 19 Jun 2017 11:46:13 -0400 (EDT) Received: from 80.146.228.71 by webprd-a31.mail.aol.com (10.72.52.208) with HTTP (WebMailUI); Mon, 19 Jun 2017 11:46:13 -0400 Date: Mon, 19 Jun 2017 11:46:13 -0400 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <15cc1086b54-5b51-1d92d@webprd-a31.mail.aol.com> In-Reply-To: <5947E5D1.2080702@posteo.de> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [80.146.228.71] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1497887175; bh=LfYbTKguuKTXaewMoK3+POJNSs0706wpDI9hX2+k0eI=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=rc/zelHvfq+pCsEKED+hsyvbb90GMicUdLehTQtzpqCphB7pHwsazmXF2zQLaljQJ h+TYbW5MpNj4gUwlSejDRZU1P8hy/K0Hoyw9eI5m4hugi8iC5IlcyF9bEMUWFPl8Ib MZGqpvaoaHSRzESo3yxo/UUOfkwrAlsojSPAYlUw= x-aol-sid: 3039ac1b01905947f1c5035a X-Scan-Signature: e39ba0db4036f4dda6b86b94bb0e598f Subject: Re: LF: EbNaut test Content-Type: multipart/alternative; boundary="----=_Part_143437_1671012616.1497887173458" 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: 12038 ------=_Part_143437_1671012616.1497887173458 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Stefan, the frequencies of recent detections (e.g. IW4DXW) on our two opds grabbers= seem to be within a mHz, so your 10 kHz derived receive LO should be ok. C= ould it be that the strong LF transmit signal is interfering with either th= e GPS itself or the 1pps samplerate detector?=20 My opds image currently shows a zoomed section around on 137517.000 which y= ou might use to check your TX frequency.=20 Domenico mentions a possible problem when using synced resampling in the TX= instance. I haven't run into that yet as I'm currently not using resamplin= g, neither for TX or RX instances (only 1pps phase-lock but no resampling).= The disadvantage on RX is that the frequency offset from the FFT center fr= equency is not tracking samplerate deviations, but this is only a small eff= ect (e.g. about 30 uHz error 30 Hz offset and 1ppm drift). One advantage of SpecLab TX with audio feedback is that the phase can recov= er from audio dropouts on the ADC and DAC side. This might potentially beco= me a problem for EbSynth on a RasPi with USB soundcard. Best 73, Markus -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: Mo, 19. Jun 2017 16:56 Betreff: Re: LF: EbNaut test That is strange indeed. Maybe something is wrong here? Maybe the old GPS mo= dule is not running properly? I had to replace a mains socket recently and = had to shut down the complete station for that. I would like to run a carrier transmission. Could someone of you check it = for frequency accuracy? Or we do it the other way. Domenico, your OP32 sign= al has always been very accurate, i remember 137485.000 Hz. Can you run a t= ransmission so i would see the same offset here maybe? Or maybe Markus, or = Riccardo? 73, Stefan Am 19.06.2017 16:27, schrieb Markus Vester:=20 >> Where does that -3.4 mHz offset come from? That's strange. I observed exactly the same frequency offset here (137499.= 9825 Hz RX LO + 30.0141 Hz offset). On the other hand, your TX signal gener= ation "should" provide a GPS-accurate frequency. The 0.3 s time lag is expected due to soundcard DAC latency. Best 73, Markus -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: Mo, 19. Jun 2017 15:44 Betreff: Re: LF: EbNaut test Hi Domenico,=20 Thanks for the detailed report and the EbNaut decode over 1159 km. It was = still in daylight, so not bad for LF in mid June and a 376 second long mess= age... Where does that -3.4 mHz offset come from? Well, i realised that i don't even need to build the XOR gate circuit. I s= imply used the PC that generates EbNaut for VLF, i.e. SpecLab, which has a = PPS+NMEA input. I choose a frequency of 12530 Hz. Then i built an LF up-con= verter (in 2011) that has a LO of 125 kHz. So i come out on 137.53 kHz. Tha= t 125 kHz LO frequency (4 MHz xtal down-divided) is PLL locked to the 10 kH= z ref output of the old Jupiter GPS, which is running here since 2010. The = 10 kHz and the 125 kHz are also used on the RX side. So i can generate stab= le signals on LF... It seems it works :-) 73, Stefan Am 19.06.2017 14:59, schrieb Domenico IZ7SLZ:=20 Hi Stefan, LF as i suspected, i found my linux-pc storage hard disk full. A new 1 TB HD = is now in order. So unfortunatly i can't give you an EbNaut report obtained using full vlfrx= -tools programs. OPDS SL session has recordered a file witch covers your 16:30 EbNaut transm= ission. I got a nice decode using almost the same offsets found by Markus D= F6NM. I have tried to use also linux ebnaut, after converting the wave file with= following shell script: ------------------ #!/bin/bash sox 06181637.wav -t dat -| =20 sed '/;/d' | ebnaut -v -dp4K19A -F29.9966 -N10 -S1 -r111.11111 -c2 -L200000 -PS -v -T72= 4.5 # |tee dk7fc.txt=20 ------------------- But it gives, of course, almost the same results. At the link http://qsl.net/i/iz7slz//DK7FC/ i have uploaded FFT raw and w= ave files, in case someone wants to try the decoding. So Stefan, congratulations for your first LF-Ebnaut transmission. Can you t= ell us how did you generate the signal ? There is a very easy and cheap method actually in use by Riccardo IW4DXW a= nd Tony IK1HGI for generating a coherent carrier for EbNaut.Congrats to Ri= ccardo for this nice idea. They are using directly the timing pulse TP5 output of the neo-8 GPS . In = fact this timing port (TP5) can be reprogrammed up to 5 MHz. The BPSK modulator consist of an XOR port in between the GPS TP5 output and= the PA driver. Cool ! 73 Domenico, IZ7SLZ =20 On 18 June 2017 at 23:44, DK7FC wrote: Thanks Markus, nice. We could exchange 1000 characters in 2 minutes, if the= Eb/N0 calculation is correct :-) Maybe i will try another one with Domenico when he is back. And is RN3AUS = reading this email? Is someone else interested in an LF EnNaut test, if the equipment is avail= able,maybe W1TAG? 73, Stefan=20 Am 18.06.2017 22:07, schrieb Markus Vester:=20 Hi Stefan, a fine and error-free decode, best with 0.3 s extra delay. A phase glitch = occured here near the middle, presumably on the receive side. Best 73, Markus -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: So, 18. Jun 2017 18:35 Betreff: Re: LF: EbNaut test PS: This time 100 Hz higher Am 18.06.2017 18:28, schrieb DK7FC:=20 Hello Markus,=20 Oh, you are right. Same message on 16:30 utc. .. I hope it works... 73, Stefan Am 18.06.2017 16:56, schrieb Markus Vester:=20 Hi Stefan, I'd like to try. But the QRG 137.43 kHz was below my opds capture range (1= 37.45 to 137.55 kHz). 73, Markus -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Verschickt: So, 18. Jun 2017 16:47 Betreff: LF: EbNaut test Hi LFers, My first EbNaut message is running at the moment. Not sure if the timing= =20 and keying is OK. Could someone check if it can be decoded? Don't make a= =20 secret out of the message. Parameters: 4K19A, 1sec, 10 char, CRC16, Start:14:36 UTC (maybe there is= =20 a timing offset between +-1 sec? pse report). 73, Stefan ------=_Part_143437_1671012616.1497887173458 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Hi Stefan,

the frequencies of recent detecti= ons (e.g. IW4DXW) on our two opds grabbers seem to be within a mH= z, so your 10 kHz derived receive LO should be ok. Could it = be that the strong LF transmit signal is interfering with either = the GPS itself or the 1pps samplerate detector?

My opds image&= nbsp;currently shows a zoomed section around on 137517.000 which = you might use to check your TX frequency. 

Domenico mentions&nb= sp;a possible problem when using synced resampling in the TX instance.=  I haven't run into that yet as I'm currently not using resamplin= g, neither for TX or RX instances (only 1pps phase-lock but no resampling).= The disadvantage on RX is that the frequency offset from the FFT center fr= equency is not tracking samplerate deviations, but this is only a smal= l effect (e.g. about 30 uHz error 30 Hz offset and 1ppm drift).
One advantage of SpecLab TX with audio feedback is that the phas= e can recover from audio dropouts on the ADC and DAC side. This might poten= tially become a problem for EbSynth on a RasPi with USB soundcard.

B= est 73,
Markus

-----Urspr=C3=BCngliche Mitteilung-----
Von: D= K7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@= blacksheep.org>
Verschickt: Mo, 19. Jun 2017 16:56
Betreff: Re: LF= : EbNaut test

That is strange indeed. Maybe something is wrong here? Maybe the old GPS module is not running properly? I had to replace a mains socket recently and had to shut down the complete station for that.
I would like to run a carrier transmission. Could someone of you check it for frequency accuracy? Or we do it the other way. Domenico, your OP32 signal has always been very accurate, i remember 137485.000 Hz. Can you run a transmission so i would see the same offset here maybe? Or maybe Markus, or Riccardo?

73, Stefan

Am 19.06.2017 16:27, schrieb Markus Vester:
>> Where does that -3.4 mHz offset come from?

That's strange. I observed exactly the same frequency offset here (137499.9825 Hz RX LO + 30.0141 Hz offset). On the other hand,&nb= sp;your TX signal generation "should" provide a GPS-accurate frequency.

The 0.3 s time lag is expected due to soundcard DAC latency.

Best 73,
Markus


-----Urspr=C3=BCngliche Mitteilung-----
Von: DK7FC <selberd= enken@posteo.de>
An: rsgb_lf_group
Hi Domenico,

Thanks for the detailed report and the EbNaut decode over 1159 km. It was still in daylight, so not bad for LF in mid June and a 376 second long message...
Where does that -3.4 mHz offset come from?

Well, i realised that i don't even need to build the XOR gate circuit. I simply used the PC that generates EbNaut for VLF, i.e. SpecLab, which has a PPS+NMEA input. I choose a frequency of 12530 Hz. Then i built an LF up-converter (in 2011) that has a LO of 125 kHz. So i come out on 137.53 kHz. That 125 kHz LO frequency (4 MHz xtal down-divided) is PLL locked to the 10 kHz ref output of the old Jupiter GPS, which is running here since 2010. The 10 kHz and the 125 kHz are also used on the RX side. So i can generate stable signals on LF...
It seems it works :-)

73, Stefan


Am 19.06.2017 14:59, schrieb Domenico IZ7SLZ:
Hi Stefan, LF

 as i suspected, i found my linux-pc storage hard disk full. A new 1 T= B HD is now in order.
So unfortunatly i can't give you an EbNaut report obtained using full vlfrx-tools programs.

OPDS SL session has recordered a file witch covers your 16:30 EbNaut transmission. I got a nice decode using almost the same offsets found by Markus DF6NM.
I have tried to use also linux ebnaut,  after converting the wave file with following shell script:
------------------
#!/bin/bash
sox 06181637.wav  -t dat  -|      &= nbsp;  
sed '/;/d' |
ebnaut -v -dp4K19A -F29.9966 -N10 -S1 -r111.11111 -c2 -L200000 -PS -v -T724.5  # |tee dk7fc.txt
-------------------

But it gives,  of course, almost the same results.

At the link http://qsl.net/i/iz7slz//DK7FC/   i have uploaded FFT raw and wave files, in case someone wants to try the decoding.

So Stefan, congratulations for your first LF-Ebnaut transmission. Can you tell us how did you generate the signal ?

There is a very easy and cheap method actually in use by Riccardo IW4DXW  and Tony IK1HGI  for generating a coherent carrier for EbNaut.Congrats to Riccardo for this nice idea.
They are using directly the timing pulse TP5 output of the neo-8 GPS . In fact this timing  port (TP5) can be reprogrammed up to 5 MHz.
The BPSK modulator consist of an XOR port in between the GPS TP5 output and the PA driver. Cool !

73 Domenico, IZ7SLZ




 



On 18 June 2017 at 23:44, DK= 7FC <selberdenken@posteo.de> wrote:
Thanks Markus, nice. We could exchange 1000 characters in 2 minutes, if the Eb/N0 calculation is correct :-)
Maybe i will try another one with Domenico when he is back. And is RN3AUS reading this email?
Is someone else interested in an LF EnNaut test, if the equipment is available,maybe W1TAG?

73, Stefan


Am 18.06.2017 22:07, schrieb Markus Vester:
Hi Stefan,

a fine and error-free decode, best with 0.3 s extra delay. A phase glitch occured here near the middle, presumably on the receive side.

Best 73,
Markus



-----Urspr=C3=BCngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>= ;
An: rsgb_lf_group <rsgb_lf_grou= p@blacksheep.org>
Verschickt: So, 18. Jun 2017 18:35
Betreff: Re: LF: EbNaut test

PS: This time 100 Hz higher

Am 18.06.2017 18:28, schrieb DK7FC:
Hello Markus,

Oh, you are right. Same message on 16:30 utc. ..
I hope it works...

73, Stefan

Am 18.06.2017 16:56, schrieb Markus Vester:
Hi Stefan,

I'd like to try. But the QRG 137.43 kHz was below my opds capture rang= e (137.45 to 137.55 kHz).

73, Markus




-----Urspr=C3=BCngliche Mitteilung-----
Von: DK7FC <selberdenken@post= eo.de>
An: rsgb_lf_group <rsgb= _lf_group@blacksheep.org>
Verschickt: So, 18. Jun 2017 16:47
Betreff: LF: EbNaut test

Hi LFers,

My first EbNaut message is running at the moment. Not sure if the timing
and keying is OK. Could someone check if it can be decoded? Don't make a
secret out of the message.

Parameters: 4K19A, 1sec, 10 char, CRC16, Start:14:36 UTC (maybe there is
a timing offset between +-1 sec? pse report).

73, Stefan


------=_Part_143437_1671012616.1497887173458--