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[195.171.43.25]) by mx.google.com with ESMTP id 10si571350wjp.35.2014.01.24.05.31.51 for ; Fri, 24 Jan 2014 05:31:52 -0800 (PST) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass header.i=@kabelmail.de Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1W6fex-00035U-Mu for rs_out_1@blacksheep.org; Fri, 24 Jan 2014 12:14:55 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1W6few-00035L-NN for rsgb_lf_group@blacksheep.org; Fri, 24 Jan 2014 12:14:54 +0000 Received: from smtpa1.mediabeam.com ([194.25.41.13]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1W6fer-0007IA-MD for rsgb_lf_group@blacksheep.org; Fri, 24 Jan 2014 12:14:53 +0000 Received: from IMAP1 (balancer7.mediabeam.com [10.100.1.80]) by smtpa1.mediabeam.com (8.13.8/8.13.1) with ESMTP id s0OCEkXw009376 for ; Fri, 24 Jan 2014 13:14:48 +0100 X-DKIM-Result: Domain=kabelmail.de Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kabelmail.de; s=mail; t=1390565688; bh=x0Ra8b4j3pAZFeWkRpJbYLvK2vl1Lbmdsxrx9mW22xg=; h=Date:From:To:Subject; b=lApNXFV0b2IPyzQq8mjmHRfvkfLO0blT5oUTmVjnGhqHEuXM0hKEh7qWU/m7Dx0Bc CQpRGYRDRUKDT6miWjarVzea5jBzi+lD3TX3RjaJ8CGH6QmnKvS6HK2anHaReJ0Cp0 y2EdOs5tDlbrzV8+Hp1RaftrXwJrpL9ladRm2qCs= Date: Fri, 24 Jan 2014 13:14:43 +0100 From: uwe-jannsen@kabelmail.de To: rsgb_lf_group@blacksheep.org Message-ID: <00a409bc5a7144c2b0888933be246758@kabelmail.de> X-Priority: 3 (Normal) MIME-Version: 1.0 X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Yes, Markus, my TX has been ZOA with SpecLab set to phase correction. all grabbers show a vy clean line never seen before. Thanks for that .USR file. But .. I had problems finding a proper soundcard. At last a new sound blaster audigi made it. But not 100%. To get the 1PPS peaks ok, the record amplifier must be set to 100% and no NMEA signs to receive. [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [194.25.41.13 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 4c1b3a9525cea91d9a699b8982ee892f Subject: Re: Re: Re: VLF: Transmit phase correction Content-Type: multipart/alternative; boundary="----642AFADDACE34499A80AEF8C10052353" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.9 required=5.0 tests=HTML_30_40,HTML_MESSAGE, NO_REAL_NAME,PRIORITY_NO_NAME 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 ------642AFADDACE34499A80AEF8C10052353 Content-type: text/plain; charset=Windows-1252 Content-Transfer-Encoding: quoted-printable Yes, Markus, my TX=A0 has been ZOA with SpecLab set to phase correction= =2E=20 all grabbers show a vy clean line never seen before=2E Thanks for that= =2EUSR file=2E =20 But=85=2E=2E=20 I had problems finding a proper soundcard=2E At last a new sound blaste= r audigi made it=2E But not 100%=2E=20 To get the 1PPS peaks ok, the record amplifier must be set to 100% and= no NMEA signs to receive=2E =20 with =A0SpecLab settings not using the phase correction the soundcard r= ecorder must be set to abt 2% to get the 1PPS peaks and NMEA ok=2E=20 With other soundcards =96 like an vy old Sound Blaster, Musen and Gener= ic=A0 - the 1PPS and the NMEA signs where ok when the record slider was= set to 100%=2E But obviously no phase correction occurred=2E Rainbow c= olours in the trace=2E=20 Ok, it is all fine now, the trace gleams in lime green, i=2Ee=2E 180=B0= locked=2E=20 GL=20 Uwe/dj8wx=20 Von: rsgb_lf_group@blacksheep=2Eorg Gesendet: 24=2E01=2E2014 10:30 An: rsgb_lf_group@blacksheep=2Eorg Betreff: Re: Re: VLF: Transmit phase correction Hi Uwe,=20 wonder if you've been testing the phase correction scheme on air last n= ight? The PA1SDB grabber is now showing a nice narrow peak in 47=B5Hz=2E= =20 I have also run an experiment with two local carriers:=A08269=2E998 fro= m anotherPC running SpecLab with phase correction, and 8270=2E000 from=A0= a decadic syntheziser to check my grabber's integrity=2E=A0Sometime in = the wee hours the amplitude of the SpecLab trace jumped up, presumably = to=A0increased leakage from a loose=A0shield connection on=A0the audio = cable=2E But both traces seemed to be glitch-free over many hours=2E=20 Best 73, =20 Markus (DF6NM)=20 ----- Original Message -----=20 From: uwe-jannsen@kabelmail=2Ede =20 To: rsgb_lf_group@blacksheep=2Eorg =20 Sent: Thursday, January 23, 2014 4:07 PM=20 Subject: Re: Re: VLF: Transmit phase correction =20 since 1407utc I was playing around with the settings=2E that caused mni= "glitches"=2E so I switch the PA off now at 1500utc to make some "dry practices"=2E until later Uwe Von: rsgb_lf_group@blacksheep=2Eorg Gesendet: 23=2E01=2E2014 13:57 An: rsgb_lf_group@blacksheep=2Eorg Betreff: Re: VLF: Transmit phase correction Hi Markus, now since 1238utc ZOA in 1pps_PLL=2Eusr mode on 8270=2E004Hz we will see GL Uwe Von: rsgb_lf_group@blacksheep=2Eorg Gesendet: 23=2E01=2E2014 00:24 An: rsgb_lf_group@blacksheep=2Eorg Kopie: Paul@abelian=2Enetcom=2Eco=2Euk Betreff: VLF: Transmit phase correction Hi Wolf, Uwe, Peter,=20 after a little experimentation, I think I have found a way to set up Sp= ecLab to=A0eliminate transmit phase=A0jumps caused by dropouts in the s= oundcard=A0output=2E=A0As a proof of concept,=A0I=A0generated an=A08269= =2E998 Hz audio=A0carrier=A0last night=2E This happened to=A0leak=A0fro= m the audio wires=A0to my VLF antenna, and produced a weak but well def= ined dash in the 42 uHz grabber window=2E=20 We can use SpecLabs GPS=A0tracking to take care of any irregularities i= n the sound input path to the ADC=2E When using the 1-pps reference wit= h=A0phaselock it can identify and correct short dropouts=2E Augmented b= y the built-in NMEA-based timestamping scheme, SpecLab can=A0in princip= le=A0even=A0provide a defined=A0absolute phase, referenced to the begin= ning of the UT day=2E =20 But the timing is always relative to the reference seen by the ADC inpu= t, and there is no way to directly sense latency variations in the buff= ering between the software=A0and the DAC output=2E Unfortunately on man= y machines,=A0buffer underflows or dropouts on the playback side seem t= o happen fairly often, especially when the PC is not left alone but is = used for other jobs on the side=2E=20 The idea is to feed back a sample of the analog output to the input, us= ing either an analog loopback (eg the audio mixer, but not a digital lo= op like VAC)=2E Or set up a pickup probe to sense antenna current or vo= ltage, which would also take care of=A0phase shifts from variable anten= na tuning=2E Then SpecLab can do a phase comparison to a=A0GPS-referenc= ed=A0internal generator, and steer the=A0frequency of an independent ou= tput oscillator to=A0bring the radiated signal=A0back to the correct ph= ase=2E=20 If you want to experiment with this method, you can download=A0the conf= iguration file =20 http://dl=2Edropboxusercontent=2Ecom/u/26404526/VLF_TX_1pps_PLL=2EUSR=A0= =20 which generates a 8270 Hz stabilised signal=2E To see how it works, tak= e a look at the circuit diagram in:=20 http://dl=2Edropboxusercontent=2Ecom/u/26404526/screenshot_VLF_TX_1pps_= PLL=2Ejpg=20 The output signal is generated by the digimode terminal block, which ca= n be set up either for a continuous carrier, or for QRSS or Opera modul= ation if you want=2E It feeds the DAC and the power amplifier through L= 5=2E The output is brought back to the left input=A0(L1) and fed to the= "E" channel of=A0a colour-DF spectrogram=2E The right channel (R1) get= s the 1pps signal from the GPS=A0which is used=A0for=A0samplerate lock=2E= Lacking an appropriate GPS unit, I'm not using NMEA timestamps here, b= ut you could choose so if your unit provides serial data=A0with proper = timing=2E=20 The=A0steady reference frequency is provided by the test signal generat= or -=A0this is where you enter your desired output frequency=2E It is f= ed to the second "H" channel of the spectrogram through R5=2E The colou= r (azimuth) of the trace=A0gives an indication of the phase difference = between L1 and R5=2E=20 The phase lock is implemented as a=A0macro in conditional actions: Ever= y 200 ms, it checks whether there is a valid probe signal at L1, and if= so, it=A0shifts=A0the digimode frequency within +-0=2E18 Hz according = to the phase difference=2E Check this by turmning the DAC=A0off and on:= =A0The trace comes back on with an arbitrary colour, but=A0it will alwa= ys revert to green (180=B0) within about three seconds=2E=A0=20 So to get started,=20 -=A0set up the analog loop path and the 1-pps,=A0=20 - load VLF_TX_1pps_PLL=2Eusr,=20 - change the=A0test signal generator=A0frequency from Uwe's 8270=2E004 = to yours, =20 -=A0set the digimode teminal to send unmodulated test tone at TX freque= ncy,=20 - enjoy!=20 Hope this may be useful=2E=20 Best 73,=20 Markus (DF6NM)=20 From: wolf_dl4yhf =20 Sent: Sunday, January 19, 2014 7:01 PM=20 To: Markus Vester =20 Cc: Paul ; Uwe Jannsen =20 Subject: Re: DJ8WX 8270=2E004 Hz - transmit phase correction? =20 Hello Markus and all, Am 19=2E01=2E2014 18:43, schrieb Markus Vester: 30 dB =2E=2E=2Enot too bad, is it?=20 Still wondering about the nature of those transmit glitches=2E Assuming= perfect GPS sync,=A0all=A0possible interruptions in the input data str= eam could be detected by the timestamp identification=2E But=A0there=A0= is still a chance for undetected=A0buffer underruns in the sound output= =2E=A0Would that affect the phase permanently?=A0Or would the average f= ill state of the FIFO buffering=A0eventually=A0be pulled back to the or= iginal lag (probably not)?=2E=20 I have been pondering a scheme where one audio channel is getting 1pps = while the other is used to=A0sample=A0the transmitter output, eg with a= small pickup loop=2E That way all phase variations in the transmit cha= in would be caught, and the=A0software oscillator could be steered to r= evert to the original phase within a few seconds=2E With timestamping,=A0= we could even prescribe=A0absolute phase, allowing comparative measurem= ents=A0across different sessions=A0many days apart=2E=20 Wolf what do you think? If it makes sense, I might try to implement=A0s= omething=A0based on the Sndinput / Sndoutpt=A0combo=2E=A0 Yes, certainl= y=2E If there was a drop-out of the audio output, we cannot be sure if = the latency between 'application' and the arrival of the sample at the = D/A-converter remains exactly the same=2E Observing the phase of the *r= adiated signal* and steering the signal generated by software to get th= e phase 'back where it belongs' would be better because it would also c= ompensate phase deviations caused by the antenna itself=2E Have a nice evening, =A0 Wolf =2E Best 73,=20 Markus ------642AFADDACE34499A80AEF8C10052353 Content-type: text/html; charset=Windows-1252 Content-Transfer-Encoding: quoted-printable

Yes, Markus, my TX  has been ZOA with SpecLab set to p= hase correction=2E
all grabbers
show a vy clean line never seen before=2E Tha= nks for that =2EUSR file=2E

But…=2E=2E

I had problems finding a proper soundcard=2E At last a new sou= nd blaster audigi made it=2E But not 100%=2E
To get the 1PPS peaks ok, the record amplifier must be set to 100% and = no NMEA signs to receive=2E

with  SpecLab settings not using the phase correction the= soundcard recorder must be set to abt 2% to get the 1PPS peaks and NME= A ok=2E

With other soundcards – like an vy old Sound Blaster, Mu= sen and Generic  - the 1PPS and the NMEA signs where ok when the r= ecord slider was set to 100%=2E But obviously no phase correction occur= red=2E Rainbow colours in the trace=2E

Ok, it is all fine now, the trace gleams in lime green, i=2Ee=2E= 180° locked=2E

GL

Uwe/dj8wx

 



Von: rsgb_lf_group@blacksheep=2Eorg
Gesendet: 24=2E01=2E2014 10:30
An: rsgb_lf_group@blacksheep=2Eorg
Betreff: Re: Re: VLF: Transmit phase correction


Hi Uwe,
 =
wonder if you= 've been testing the phase correction scheme on air last night? The PA1SDB grabber is now showing a nice narr= ow peak in 47µHz=2E
 =
I have also r= un an experiment with two local carriers: 8269=2E998 from anotherPC running SpecLab with phase cor= rection, and 8270=2E000 from a decadic syntheziser to check my grabber's integrity=2E Sometime in the wee hours the amplitude of the SpecLab trace jumped up, presumably to increased = leakage from a loose shield connection on the audio cable=2E But both= traces seemed to be glitch-free over many hours=2E
 =
Best 73,
Markus (DF6NM= )
 =
----- Original Message -----
Sent: Thursday, January 23, 2014 4:07 PM
Subject: Re: Re: VLF: Transmit phase correction

since 1407utc I was playing around with the settings=2E that caused mni "glitches"=2E
so I switch the PA off now at 1500utc to make some "dry practices"=2E
until later
Uwe

Von: rsgb_lf_group@bl= acksheep=2Eorg
Gesendet: 23=2E01=2E2014 13:57
An: rsgb_lf_group@bla= cksheep=2Eorg
Betreff: Re: VLF: Transmit phase correction


Hi Markus,
now since 1238utc ZOA in 1pps_PLL=2Eusr mode on 8270=2E004Hz
we will see
GL
Uwe

Von: rsgb_lf_group@blacksheep=2Eorg
Gesendet: 23=2E01=2E2014 00:24
An: rsgb_lf_group@blacksheep=2Eorg
Kopie: Paul@abelian=2Enetcom=2Eco=2Euk
Betreff: VLF: Transmit phase correction


Hi Wolf, Uwe, Peter,
 =
after a littl= e experimentation, I think I have found a way to set up SpecLab to e= liminate transmit phase jumps caused by dropouts in the soundcard output=2E As a proof of concept, I genera= ted an 8269=2E= 998 Hz audio carrier last night=2E This happened to leak f= rom the audio wires to my VLF antenna, and produced a weak but well define= d dash in the 42 uHz grabber window=2E
 =
We can use Sp= ecLabs GPS tracking to take care of any irregularities in the sound input= path to the ADC=2E When using the 1-pps reference with phaselock it can id= entify and correct short dropouts=2E Augmented by the built-in NMEA-based timestam= ping scheme, SpecLab can in principle even provide a defined absolute phase, referenced to the beginning of the UT day=2E
 =
But the timin= g is always relative to the reference seen by the ADC input, and there is no way to= directly sense latency variations in the buffering between the software and= the DAC output=2E Unfortunately on many machines, buffer underflows or dro= pouts on the playback side seem to happen fairly often, especially when the PC i= s not left alone but is used for other jobs on the side=2E
 =
The idea is t= o feed back a sample of the analog output to the input, using either an analog loop= back (eg the audio mixer, but not a digital loop like VAC)=2E Or set up a pickup= probe to sense antenna current or voltage, which would also take care of ph= ase shifts from variable antenna tuning=2E Then SpecLab can do a phase comp= arison to a GPS-referenced internal generator, and steer the frequ= ency of an independent output oscillator to bring the radiated signal = ;back to the correct phase=2E
 =
If you want t= o experiment with this method, you can download the configuration file <= /div>
which generat= es a 8270 Hz stabilised signal=2E To see how it works, take a look at the circuit diagram in:
http://dl=2Edropboxuserc= ontent=2Ecom/u/26404526/screenshot_VLF_TX_1pps_PLL=2Ejpg
 =
The output si= gnal is generated by the digimode terminal block, which can be set up either fo= r a continuous carrier, or for QRSS or Opera modulation if you want=2E It f= eeds the DAC and the power amplifier through L5=2E The output is brought back to= the left input (L1) and fed to the "E" channel of a colour-DF spectrog= ram=2E The right channel (R1) gets the 1pps signal from the GPS which is used for samplerate lock=2E Lacking an appropriate GPS unit, = I'm not using NMEA timestamps here, but you could choose so if your unit provid= es serial data with proper timing=2E
 =
The stea= dy reference frequency is provided by the test signal generator - this is where= you enter your desired output frequency=2E It is fed to the second "H" chan= nel of the spectrogram through R5=2E The colour (azimuth) of the trace gives = an indication of the phase difference between L1 and R5=2E
 =
The phase loc= k is implemented as a macro in conditional actions: Every 200 ms, it ch= ecks whether there is a valid probe signal at L1, and if so, it shifts&= nbsp;the digimode frequency within +-0=2E18 Hz according to the phase difference= =2E Check this by turmning the DAC off and on: The trace comes back on = with an arbitrary colour, but it will always revert to green (180°) wi= thin about three seconds=2E 
 =
So to get started,
- set up= the analog loop path and the 1-pps, 
- load VLF_TX_1pps_PLL=2Eusr,
- change the&= nbsp;test signal generator frequency from Uwe's 8270=2E004 to yours, =
- set th= e digimode teminal to send unmodulated test tone at TX frequency,
- enjoy!
 =
Hope this may= be useful=2E
 =
Best 73,
Markus (DF6NM)
 =
=
Sent: Sunday, January 19, 2014 7:01 PM
Subject: Re: DJ8WX 8270=2E004 Hz - transmit phase correction?
<= span style=3D"font-family: arial; font-size: 13px;">
Hello Markus and all,

Am 19=2E01=2E2014 18:43, schrieb Markus Vester:
30 dB =2E=2E=2E= not too bad, is it?
 
S= till wondering about the nature of those transmit glitches=2E Assuming perfe= ct GPS sync, all possible interruptions in the input data stream cou= ld be detected by the timestamp identification=2E But there is stil= l a chance for undetected buffer underruns in the sound output=2E = ;Would that affect the phase permanently? Or would the average fill state= of the FIFO buffering eventually be pulled back to the original lag (probably not)?=2E
 
I= have been pondering a scheme where one audio channel is getting 1pps while the ot= her is used to sample the transmitter output, eg with a small pickup= loop=2E That way all phase variations in the transmit chain would be caught, an= d the software oscillator could be steered to revert to the original= phase within a few seconds=2E With timestamping, we could even prescribe absolute phase, allowing comparative measurements a= cross different sessions many days apart=2E
 
W= olf what do you think? If it makes sense, I might try to implement something based on the Sndinput / Sndoutpt combo=2E 
Yes, certainly=2E If there was a drop-out of the audio output, we cannot be sure if the latency betwee= n 'application' and the arrival of the sample at the D/A-converter remain= s exactly the same=2E Observing the phase of the *radiated signal* and steering t= he signal generated by software to get the phase 'back where it belongs' would be= better because it would also compensate phase deviations caused by the antenna itself=2E

Have a nice evening,
  Wolf =2E

B= est 73,
M= arkus
 
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