Return-Path: Received: from rly-md09.mx.aol.com (rly-md09.mail.aol.com [172.20.29.147]) by air-md05.mail.aol.com (v121.4) with ESMTP id MAILINMD052-92747b002c8372; Mon, 11 Feb 2008 03:10:12 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-md09.mx.aol.com (v121.4) with ESMTP id MAILRELAYINMD097-92747b002c8372; Mon, 11 Feb 2008 03:09:46 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1JOThe-00062j-UA for rs_out_1@blacksheep.org; Mon, 11 Feb 2008 08:07:50 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1JOThe-00062a-5k for rsgb_lf_group@blacksheep.org; Mon, 11 Feb 2008 08:07:50 +0000 Received: from ug-out-1314.google.com ([66.249.92.172]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1JOThZ-0002cy-Jc for rsgb_lf_group@blacksheep.org; Mon, 11 Feb 2008 08:07:50 +0000 Received: by ug-out-1314.google.com with SMTP id a2so253242ugf.13 for ; Mon, 11 Feb 2008 00:07:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; bh=9Kd4BYGCtNBAGao6t0QUGuhRBts8MrdQzQaae0SHo18=; b=KA6oO4KIw8iOQW2bRAocyDH7ImwrDm1/zFNONwOHpeY2XmOfzPT02EOsmUo+2tZRVQFGpvtFv8xtbfa3y9SFVIukvoOtt3OpcXjbI9F4PaYjGbtuYNmo9TwU6DjtLdmgCVE5H/38PiWtdbd5WMk56VYfHOU1tQFIlQtQXIP/FHQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; b=I1tHm5TkkVRxlZ7OZcradi9Smupq1oQo0uzsnVnaUsgPn2V9QeQgzBN4vN5ewu8z78M5uwT7VMxQWYc2pRuu46gvVohiJCESTwnQQThzmLTtFtqJb4P/tI9QfQ1XAfahpwSLjMXBHHm+IbXhb3qOADnBuGn5ymvcOIuIo9LBaGA= Received: by 10.67.116.7 with SMTP id t7mr8779932ugm.38.1202717264998; Mon, 11 Feb 2008 00:07:44 -0800 (PST) Received: by 10.67.10.15 with HTTP; Mon, 11 Feb 2008 00:07:44 -0800 (PST) Message-ID: Date: Mon, 11 Feb 2008 08:07:44 +0000 From: "Andy Talbot" To: rsgb_lf_group@blacksheep.org In-Reply-To: <0f9b01c86bf5$dda5a880$0300000a@AGB> MIME-Version: 1.0 References: <001e01c86bd7$38723a90$0301a8c0@ken> <000701c86bed$4f9a69c0$0900a8c0@Lark> <0f9b01c86bf5$dda5a880$0300000a@AGB> DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: Windows Beacon TX/RX Software .. can anyone code such a thing ? Content-Type: multipart/alternative; boundary="----=_Part_25850_14855595.1202717264991" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=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-IP: 193.82.116.20 X-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_helo : n X-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_822_from : ? X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m021.2 ; domain : googlemail.com DKIM = 1 X-Mailer: Unknown (No Version) ------=_Part_25850_14855595.1202717264991 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline A problem with the scheme you suggest, Graham, is that PC clocks maintain time badly, and will drift by several seconds overnight which makes a mockery of the idea of precisely timed sequential listening. They may be able to acheive Internet synchronisation, but can this be set up to automatically update at the rate you will need, ie. every hour or two based on some of the clock drifts I have seen. That is why the existing beacon chains, both 5MHz and the IBP set, use GPS timing. Passive receiving stations have their timekeeping reset by the actual 5MHz transmissions themselves. On your website, you do mention MSF timing, but to do that in real time would consume another receiver / soundcard channel. GPS is the only obvious way to go for transmitting stations. PCs are not reknowned for their timekeeping abilities! Otherwise, the software is straightforward, although rather a waste of a PC. If the GPS is available, then a =A31 PIC is all you need to control an= d key a standalone transmitter that doesn't need soundcard drive. Andy G4JNT www.scrbg.org/g4jnt On 10/02/2008, Graham wrote: > > Hi all, > > > > This is something that may be of interest .. To a programmer or two or > three ? There exists collectively the expertise, but can anyone see a way > of > producing the system? > > > The idea came initially from the 'Beacon Bedlam' , that existed south of > Watford gap .. about the only time the skip distance on 500 was 'useful' > in > that band conditions in the north west where quite quiet, later to prove > a > hindrance, > > > > There already exists a similar system on 5 Mhz , however the transmission > sites are defined and participation is only possible by 'passive > reception' > not too appealing for 'experimentation' This is a 'proposal' the concept > is > proven , but 'we' need the > services of a programmer or two !! Similar thing's exist but are coded to > use 'pics' , > > > > One of the main criteria is , that 'anyone' with a windows based pc should > be able to download and install the tx/rx software and join in, be it as > a > TX station, simply claim a 'time slot' , or a passive observer being > presented with all 5 slots as a amplitude/time plot. > > > > One of the main attractions would be : TX stations will be able > to observe > the other beacons in the chain , eliminating the lonely vigil of being in > perm ante > > transmit mode, while providing , at a glance, band conditions for all > involved as well as reducing tx duty cycle time ! > > > > The number of TX stations is proposed as 5 in the chain , more may be > possible , but the time control factor may prove too difficult to achieve > within windows , but cw type software in beacon mode would appear > top make > a reasonable job of time control ? > > Click on > http://groups.google.com/group/uk500khz/web/the-big-beacon-project > - or copy & paste it into your browser's address bar if that doesn't > work. > > > > > > -- ------=_Part_25850_14855595.1202717264991 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
A problem with the scheme you suggest, Graham, is that PC clocks mainta= in time badly, and will drift by several seconds overnight which makes=20= a mockery of the idea of precisely timed sequential listening.  They ma= y be able to acheive Internet synchronisation, but can this be set up to aut= omatically update at the rate you will need, ie. every hour or two based on=20= some of the clock drifts I have seen.
 
That is why the existing beacon chains, both 5MHz and the IBP set, use=20= GPS timing.  Passive receiving stations have their timekeeping res= et by the actual 5MHz transmissions themselves.  On your website, you d= o mention MSF timing, but to do that in real time would consume another rece= iver / soundcard channel.    GPS is the only obvious way to g= o for transmitting stations.   PCs are not reknowned for their tim= ekeeping abilities!
 
Otherwise, the software is straightforward, although rather a wast= e of a PC.   If the GPS is available, then a =A31 PIC is all you n= eed to control and key a standalone transmitter that doesn't need s= oundcard drive.
 
Andy  G4JNT
www.scr= bg.org/g4jnt
 
 
On 10/02/2008, Graham <g8fzk@g8fzk.fsne= t.co.uk> wrote:
Hi all,



This is som= ething that may be of interest  .. To a programmer or two or
th= ree ? There exists collectively the expertise, but can anyone see a way of producing the system?


The idea  came initially from the= 'Beacon Bedlam' , that existed south of
Watford gap .. about the= only time the skip distance on 500 was 'useful' in
that band con= ditions in the north west where quite quiet, later to  prove a
hindrance,



There already exists a similar system on 5 Mhz , h= owever the transmission
sites are defined and  participation is= only possible by 'passive reception'
not too appealing for '= experimentation' This is a 'proposal' the concept is
proven , but 'we' need the
services of a programmer or two !! Sim= ilar thing's exist but are coded to
use 'pics' ,


<= br>One of the main criteria is , that 'anyone' with a windows based=20= pc should
be able to download and install the tx/rx  software and join in, b= e it as a
TX station, simply claim a 'time slot' ,  or=20= a passive observer being
presented with all 5 slots as a amplitude/time p= lot.



One of the  main attractions would be : TX stations will be ab= le to  observe
the other beacons in the chain , eliminating the= lonely vigil of being in
perm ante

transmit mode, while providing= , at a glance, band conditions  for all
involved as well as reducing tx duty cycle time !



The number=20= of TX stations is proposed as 5 in the chain , more may be
possible , but= the time control factor may prove too difficult to achieve
within window= s , but cw type software in beacon mode would appear top  make
a reasonable job of time control ?

Click on http://groups.google.c= om/group/uk500khz/web/the-big-beacon-project
- or copy & paste it= into your browser's address bar if that doesn't
work.








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