Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-da01.r1000.mx.aol.com (Internet Inbound) with ESMTP id A9FEC38000091; Sun, 25 Sep 2011 08:06:21 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1R7nSY-0005wX-6b for rs_out_1@blacksheep.org; Sun, 25 Sep 2011 13:05:26 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1R7nSX-0005wO-Hq for rsgb_lf_group@blacksheep.org; Sun, 25 Sep 2011 13:05:25 +0100 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1R7nSW-0001Nd-34 for rsgb_lf_group@blacksheep.org; Sun, 25 Sep 2011 13:05:25 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id p8PC5M2N005249 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sun, 25 Sep 2011 14:05:22 +0200 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id p8PC5MHd021463 for ; Sun, 25 Sep 2011 14:05:22 +0200 Message-ID: <4E7F18E5.6090402@iup.uni-heidelberg.de> Date: Sun, 25 Sep 2011 14:04:53 +0200 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= 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: <976E96347FDF49FEB91588B891BF47AF@White> <4E7E5E90.8070404@iup.uni-heidelberg.de> In-Reply-To: X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,RATWARE_GECKO_BUILD=1.426 Subject: LF: Jupiter GPS... Content-Type: multipart/alternative; boundary="------------000801060204090304020504" 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 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:498753376:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d40494e7f193d4204 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. --------------000801060204090304020504 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by relay.uni-heidelberg.de id p8PC5M2N005249 Hello Gary, I currently can't find the module on ebay "we" are using. If you seach=20 for "jupiter Rockwell GPS" then i usually found some of these modules.=20 Maybe they will appear in some time again. I just found that=20 http://www.ebay.com/itm/Navman-jupiter-T-Tu60-GPS-Kit-1pps-10khz-GPS-Modu= le-/260790984470?pt=3DLH_DefaultDomain_0&hash=3Ditem3cb85a9f16 which will probably work too. It also has a 10 kHz output but i didn't=20 read about the antenna plug. This is the antenna "we" use:=20 http://www.ebay.co.uk/itm/27db-GPS-antenna-rockwell-gps-Motorola-GPS-Modu= le-/300437185138?pt=3DLH_DefaultDomain_0&hash=3Ditem45f373a272 73, Stefan/DK7FC Am 25.09.2011 11:17, schrieb Gary - G4WGT: > Hi Stefan & All, > > Thanks for your comments & suggestions, I like the cheap GPS idea best=20 > as running more & more app's on the PC causes more & more hiccups. I=20 > presume the GPS module would be a stand alone device, any help with=20 > this method would be appreciated. > > Thanks & 73, > > Gary - G4WGT. > > > 2011/9/24 Stefan Sch=E4fer > > > Hello Gary, > > About sound card locking on LF: Actually its the same like on VLF > except the need for injecting a reference frequency. > If you decide to receive VLF in a separate SL instance and maybe > even separate soundcard (e.g. a 3 EUR USB soundcard from amazon) > then you lock that soundcard as usual to your VLF reference signal > such as GQD and generate e.g. 10 kHz on the output, which will be > locked too then. Then you can inject this 10 kHz ref signal to the > LF soundcard... > Or buy such a cheep GPS receiver instead, as often suggested here. > My whole VLF RX, LF RX and LF TX system is based on that 10 kHz > reference signal from the GPS module... > > 73, and thanks for the grabber! :-) > > Stefan/DK7FC > > Am 24.09.2011 21 :12, schrieb Gary - G4WGT: >> Hi Marcus, LF, >> >> Pleased it provided useful feedback. >> >> I am hoping to optimise the system, both from the receiver >> stability & SpecLab. The receiver is quite good but does show >> temperature stability issues at these narrow systems. I am >> considering trying a similar sound card receiver to the one >> Stefan DK7FC has recently posted in his mails. >> >> I am not at all sure about sound card sampling correction at this >> frequency range, I have no problem at the 8.970kHz range with >> using the MSK transmissions at VLF but with the narrow bandwidth >> of the system at 137kHz it presents a different situation for me. >> >> Thank you for your suggestions, I will try them in due course. >> >> 73, Gary - G4WGT. >> >> >> On 24 September 2011 17:55, Markus Vester > > wrote: >> >> Hi Gary, >> this is excellent, and much appreciated! I had >> basically tried to provide a readable signature on Chris' >> grabbers, but in the end QRSS 1200 turned out to be a bit >> fast for those. I guess the general concept is more suitable >> for straight unmodulated carriers... >> Your screenshot reveals my transmit instability near the end >> of the "N", when my (DHO-based) samplerate locking >> temporarily failed, and the audio frequency jumped by 20 mHz. >> Do you have plans for further optimization? The Loran line >> visible on 137780.419 (Anthorn et al) may come in handy to >> evaluate sensitivity and stability during development. >> One thing I would perhaps suggest is to activate the "one >> pixel per FFT bin" option in Speclab. If you don't, and >> zoom in instead, the brightness of each pixel is driven by >> the highest power from a number of adjacent FFT bins, which >> in effect increases the visible noise level significantly. Of >> course the downside is that the visible range becomes quite >> narrow, requiring TX stations to cuddle closely around a >> prescribed QRG to be seen on the grabber slot. On the other >> hand, you can still move the slot around a posteriori, and >> manually search for possible missed activity. >> Best 73, and thanks >> Markus (DF6NM) >> >> *From:* Gary - G4WGT >> *Sent:* Saturday, September 24, 2011 12:26 PM >> *To:* LF Group (RSGB) >> *Subject:* LF: DF6NM 23-09-2011 >> >> Hi Marcus, LF, >> >> Please forgive the frequency accuracy & stability on my >> experimental very slow (2 mHz) SpecLab screen but the signal >> is clearly visible. >> >> Receiver - JRC NRD-345 >> Antenna - PA0RDT Mini-Whip at 9 metres >> >> 73 >> >> Gary - G4WGT >> >> > --------------000801060204090304020504 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello Gary,

I currently can't find the module on ebay "we" are using. If you seach for "jupiter Rockwell GPS" then i usually found some of these modules. Maybe they will appear in some time again. I just found that http://www.ebay.com/itm/Navman-jupiter-T-Tu60-GPS-Kit-1pps-10khz-GPS-Module-/260790984470?pt=LH_DefaultDomain_0&hash=item3cb85a9f16
which will probably work too. It also has a 10 kHz output but i didn't read about the antenna plug.

This is the antenna "we" use: http://www.ebay.co.uk/itm/27db-GPS-antenna-rockwell-gps-Motorola-GPS-Module-/300437185138?pt=LH_DefaultDomain_0&hash=item45f373a272

73, Stefan/DK7FC


Am 25.09.2011 11:17, schrieb Gary - G4WGT:
Hi Stefan & All,

Thanks for your comments & suggestions, I like the cheap GPS idea best as running more & more app's on the PC causes more & more hiccups. I presume the GPS module would be a stand alone device, any help with this method would be appreciated.

Thanks & 73,

Gary - G4WGT.


2011/9/24 Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de>
Hello Gary,

About sound card locking on LF: Actually its the same like on VLF except the need for injecting a reference frequency.
If you decide to receive VLF in a separate SL instance and maybe even separate soundcard (e.g. a 3 EUR USB soundcard from amazon) then you lock that soundcard as usual to your VLF reference signal such as GQD and generate e.g. 10 kHz on the output, which will be locked too then. Then you can inject this 10 kHz ref signal to the LF soundcard...
Or buy such a cheep GPS receiver instead, as often suggested here. My whole VLF RX, LF RX and LF TX system is based on that 10 kHz reference signal from the GPS module...

73, and thanks for the grabber! :-)

Stefan/DK7FC

Am 24.09.2011 21:12, schrieb Gary - G4WGT:
Hi Marcus, LF,

Pleased it provided useful feedback.

I am hoping to optimise the system, both from the receiver stability & SpecLab. The receiver is quite good but does show temperature stability issues at these narrow systems. I am considering trying a similar sound card receiver to the one Stefan DK7FC has recently posted in his mails.

I am not at all sure about sound card sampling correction at this frequency range, I have no problem at the 8.970kHz range with using the MSK transmissions at VLF but with the narrow bandwidth of the system at 137kHz it presents a different situation for me.

Thank you for your suggestions, I will try them in due course.

73, Gary - G4WGT.


On 24 September 2011 17:55, Markus Vester <markusvester@aol.com> wrote:
Hi Gary,
 
this is excellent, and much appreciated! I had basically tried to provide a readable signature on Chris' grabbers, but in the end QRSS 1200 turned out to be a bit fast for those. I guess the general concept is more suitable for straight unmodulated carriers...
 
Your screenshot reveals my transmit instability near the end of the "N", when my (DHO-based) samplerate locking temporarily failed, and the audio frequency jumped by 20 mHz. Do you have plans for further optimization? The Loran line visible on 137780.419 (Anthorn et al) may come in handy to evaluate sensitivity and stability during development.
 
One thing I would perhaps suggest is to activate the "one pixel per FFT bin" option in Speclab. If you don't, and zoom in instead, the brightness of each pixel is driven by the highest power from a number of adjacent FFT bins, which in effect increases the visible noise level significantly. Of course the downside is that the visible range becomes quite narrow, requiring TX stations to cuddle closely around a prescribed QRG to be seen on the grabber slot. On the other hand, you can still move the slot around a posteriori, and manually search for possible missed activity.
 
Best 73, and thanks
 
Markus (DF6NM)
 

Sent: Saturday, September 24, 2011 12:26 PM
Subject: LF: DF6NM 23-09-2011

Hi Marcus, LF,

Please forgive the frequency accuracy & stability on my experimental very slow (2 mHz) SpecLab screen but the signal is clearly visible.

Receiver - JRC NRD-345
Antenna - PA0RDT Mini-Whip at 9 metres

73

Gary - G4WGT



--------------000801060204090304020504--