Return-Path: X-Spam-DCC: paranoid 1181; Body=3 Fuz1=3 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id t8PEfL4R029201 for ; Fri, 25 Sep 2015 16:41:21 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ZfU8j-0004wx-Vc for rs_out_1@blacksheep.org; Fri, 25 Sep 2015 15:38:21 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ZfU8j-0004wo-Cw for rsgb_lf_group@blacksheep.org; Fri, 25 Sep 2015 15:38:21 +0100 Received: from mail-oi0-f42.google.com ([209.85.218.42]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.86) (envelope-from ) id 1ZfU7j-0007wT-4w for rsgb_lf_group@blacksheep.org; Fri, 25 Sep 2015 15:38:20 +0100 Received: by oiev17 with SMTP id v17so59098326oie.1 for ; Fri, 25 Sep 2015 07:37:02 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=IqY8RTVtJKqNQoWtOjLdjvJBVUbTXIYtpF1jOh83AS8=; b=bCUBDVYSH6w3CbXheROSGTloE7jWt73P+Ej9FvpTIPwlzNSq2BTYbAHuTvC1LWBM9k kSpnbXdTA2QCVCTHrHNbhvcfks1YeGpuBB0Y5Heyj7EJnSz6wjuVwyoLeDw7aTpbFJLw o3xOpQ/JZg+ac0KodPbPHkdUxTYq8mrVcHwD4uyDG20/R1P3HHvc6okmPbdrY17Sm4VN zsVxwi6aLP4bS+9WhXcK6c2q+swq5E4rHZZ91ilx/gRyulmdbFNBnwEBIYAxNnkad2Uv 7I0CXtTa1PRdh3Z26Rbhh8SkHQWcIfcO/s+/RvbepMSWOM2UL77FoXhpjNslcCel5UFo 9nRA== MIME-Version: 1.0 X-Received: by 10.202.190.87 with SMTP id o84mr3048123oif.111.1443191822154; Fri, 25 Sep 2015 07:37:02 -0700 (PDT) Received: by 10.202.77.207 with HTTP; Fri, 25 Sep 2015 07:37:02 -0700 (PDT) In-Reply-To: References: <5601EC9F.2010607@gmail.com> Date: Fri, 25 Sep 2015 16:37:02 +0200 Message-ID: From: Domenico IZ7SLZ To: "rsgb_lf_group@blacksheep.org" X-Scan-Signature: 611f9af8a0f6ba007b1ec6dce409caf4 Subject: Re: LF: Coherent BPSK on LF using EbNaut Content-Type: multipart/alternative; boundary=001a113d6772e7027c0520934741 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 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 4146 --001a113d6772e7027c0520934741 Content-Type: text/plain; charset=UTF-8 Hello Andy, all thanks for interesting at this test. Yes, Spectrum Lab is the right program to manage the audio from receiver also in this case. The SL configuration used in LF_EbNaut experiment basically is the same of the DF6NM OPDS setup downloadable at Markus' site: http://df6nm.bplaced.net/opera/opds.zip Markus, as usual, includes all informations necessary to do the proper changes according to the hardware at disposal. In my setup, i used SL to do many things: calibrate the sample-rate, manage the ptt at scheduled time, generate a precise tone to drive my SSB exciter, create some screenshots of the waterfall and - most important - export, every 10 minutes, the FFT raw data of the reception periods. Markus will explain better than me this matter, but exporting FFT instead of .WAV file seems a good solution to avoid some issues encountered with the .wav recording function of SL. He wrote a program (named ebnaut_ifft2.exe) able to convert FFT raw data to wav file, inserting the appropriate timestamp. After this conversion, Ebnaut-rx can be used, but it needs of some - very sensitive - offset entry. For that, you need to become skilled with the use of some other Markus' tools that plot the symbol phase before the full EbNaut-rx search. But, if the clock and the frequency have very small drift in both TX and RX sides, than you can use the same measured parameters to catch the next transmitted messages. 73, Domenico (iz7slz) On 25 September 2015 at 13:23, Andy Talbot wrote: > EbAnut is a new one here - I hadn't heard of it. After Googling I found > the page and read up / downloaded the software. Unfortunately, I see it > is not standalone, and requires Spectrum lab to act as the audio "front > end" to take in the Received audio, downconvert to a baseband I/Q and store > that as a .WAV file. So downloaded Spectrum lab and tying to wade through > how to use that. > > Could you perhaps give a short cut simple explanation of how to set up > Spectrum lab to do that - it looks to be a very complex bit of software to > drive. > the EbNaut Tx and Rx programmes, in contrast, look very simple to use and > it would be goo dto get more people using sensitive coherent signalling > such as this. > > Some years ago I proposed GPS / UTC seconds locked coherent signalling on > LF, but didn't have the expertise to write the software - and certainly not > to implement strong FEC ! > > Andy G4JNT > > > On 23 September 2015 at 01:04, IZ7SLZ wrote: > >> Hello LF, >> >> I am pleased to report a successful "Coherent BPSK" QSO between DF6NM and >> IZ7SLZ on LF using EbNaut program of Paul Nicholson. >> QSO took place in the night between Friday 2015-09-18 and Saturday >> 2015-09-19 . >> >> I think it was the first time that anyone tried this on 137 kHz ! >> >> Frequencies used were 137510.00 Hz (DF6NM) and 137502.12 (IZ7SLZ). >> >> We exchange messages of 16 characters in coherent BPSK with UT >> synchronous symbols, using a symbol period of 1 second and 8K19A scheme >> coding. >> >> Software used were the Windows' versions of EbNaut-TX and EbNaut-RX (tnx >> to P. Nicholson: your software is working without problems!). >> Also Spectrum Lab (tnx Wolf !) was used to export FFT data, in a similar >> way of the Markus' OPDS setup. >> Other programs, written by Markus, were used: one to convert FFT >> exported data for the EbNaut entry and another to search for the best >> frequency and time offsets. >> >> There was not much phase drift during the qso and in other test >> transmissions, since we reach a good frequency stability at both ends >> thanks to Rubidium Reference Oscillator (Markus side) and a good quality >> OCXO from my side. >> >> You can see reported symbol / carrier EbN0 and also the messages >> exchanged, in the attached screen-shots taken at both ends. >> >> We hope now to joint other stations that want to challenge the timing and >> frequency accuracy, to have a QSO in LF close to the Shannon limit. >> >> Markus DF6NM, will report soon all particulars and his comments of the >> experiment. Thanks in advance Markus! >> >> 73, Domenico (iz7slz) >> >> >> >> > --001a113d6772e7027c0520934741 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hello Andy,=C2=A0 all
thanks for interestin= g at this test.

Yes, Spectrum Lab is the right pro= gram to manage the audio from receiver also in this case. The SL configurat= ion used in LF_EbNaut experiment basically is=C2=A0the=C2=A0same of the DF6= NM OPDS setup =C2=A0downloadable at Markus' site:

<= div>http://df6nm.bplace= d.net/opera/opds.zip

Markus, as usual, include= s all informations necessary to do the proper changes according to the hard= ware at disposal.

In my setup, i used SL to do man= y things: calibrate the sample-rate,=C2=A0 manage the ptt at scheduled time= ,=C2=A0 generate a precise tone to drive my SSB exciter,=C2=A0 create some = screenshots of the waterfall and - most important -=C2=A0 export, every 10 = minutes, =C2=A0the FFT raw data of the reception periods.

Markus will explain better than me this matter, but exporting FFT i= nstead of .WAV file=C2=A0seems a good solution to avoid some issues encount= ered with the =C2=A0.wav=C2=A0 recording function of SL.
He wrote= a program (named ebnaut_ifft2.exe) able to convert FFT raw data=C2=A0=C2= =A0to wav file, =C2=A0inserting the appropriate timestamp.

After this conversion, =C2=A0Ebnaut-rx can be used, but it needs o= f some - very sensitive - =C2=A0offset entry. For that, =C2=A0you need to b= ecome skilled with the use of=C2=A0some other Markus' tools that plot t= he symbol=C2=A0phase before the full EbNaut-rx search.
=C2=A0
But, if the=C2=A0clock =C2=A0and the =C2=A0frequency have very small= drift in both TX and RX sides, than you can use the same measured paramete= rs=C2=A0to catch the next transmitted messages.

7= 3, Domenico (iz7slz)

<= br>
On 25 September 2015 at 13:23, Andy Talbot <andy.g4jnt@gmail.com> wrote:
EbAnut is a new one here - I hadn't heard of= it.=C2=A0=C2=A0 After Googling I found the page and read up / downloaded t= he software.=C2=A0=C2=A0 Unfortunately, I see it is not standalone, and req= uires Spectrum lab to act as the audio "front end" to take in the= Received audio, downconvert to a baseband I/Q and store that as a .WAV fil= e.=C2=A0=C2=A0 So downloaded Spectrum lab and tying to wade through how to = use that.

Could you perhaps give a short cut simpl= e explanation of how to set up Spectrum lab to do that - it looks to be a v= ery complex bit of software to drive.
the EbNaut Tx and Rx progra= mmes, in contrast, look very simple to use and it would be goo dto get more= people using sensitive coherent signalling such as this.

Some years ago I proposed GPS / UTC seconds locked coherent signall= ing on LF, but didn't have the expertise to write the software - and ce= rtainly not to implement strong FEC !

Andy=C2=A0 G= 4JNT

=
On 23 September 2015 at 01:04, IZ7SLZ <iz7slz.domenico@gmail.com> wrote:
Hel= lo LF,

I am pleased to report a successful "Coherent BPSK" QSO between D= F6NM and IZ7SLZ on LF using EbNaut program of Paul Nicholson.
QSO took place in the night between Friday 2015-09-18 and Saturday 2015-09-= 19 .

I think it was the first time that anyone tried this on 137 kHz !

Frequencies used were 137510.00 Hz (DF6NM) and 137502.12 (IZ7SLZ).

We exchange messages of 16 characters in coherent BPSK with UT synchronous = symbols, using a symbol period of 1 second and 8K19A scheme coding.

Software used were the Windows' versions of EbNaut-TX and EbNaut-RX (tn= x to P. Nicholson: your software is working without problems!).
Also Spectrum Lab (tnx Wolf !) was used to export FFT data, in a similar wa= y of the Markus' OPDS setup.
Other programs,=C2=A0 written by Markus,=C2=A0 were used: one=C2=A0 to conv= ert FFT exported data for the EbNaut entry and another to search for the be= st frequency and time offsets.

There was not much phase drift during the qso and in other test transmissio= ns, since we reach a good frequency stability at both ends thanks to Rubidi= um Reference Oscillator (Markus side) and a good quality OCXO from my side.=

You can see reported symbol / carrier EbN0 and also the messages exchanged,= =C2=A0 in the attached screen-shots taken at both ends.

We hope now to joint other stations that want to challenge the timing and f= requency accuracy, to have a QSO in LF close to the Shannon limit.

Markus DF6NM, will report soon all particulars and his comments of the expe= riment. Thanks in advance Markus!

73, Domenico (iz7slz)





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