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1579RE: [dxatlas] Re: Timing Question

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  • Dave
    Nov 17, 2009
    • 0 Attachment
      Here's the results:

      ________________1______2______3_______4______5______6______7

      Download: 7.93Mb/s 6.92 7.28 7.70 6.47 6.39 7.24
      Upload: 4.80Mb/s 4.44 4.16 4.76 4.59 4.59 4.47
      Ping: 59ms 57 58 56 59 59 61

      Server: Denver, CO


      Dave
      DM78qg // KA0SWT
      /++++++++++++++++++++++++++++++++/





      -----Original Message-----
      From: dxatlas_group@yahoogroups.com [mailto:dxatlas_group@yahoogroups.com]
      On Behalf Of vk4iu
      Sent: Tuesday, November 17, 2009 22:15
      To: dxatlas_group@yahoogroups.com
      Subject: [dxatlas] Re: Timing Question

      Back again, Dave.

      The PC should be no problems.

      Looking at COMCAST.COM, my guess is you have a Cable Internet connection.
      Do you know the speed? 1.5mega bits per second download?
      Upload 64k? No matter, that's the "gloss on the brochure" anyway.

      Go to www.speedtest.net. It will suggest a server to test. Report back what
      speed you actually get - do it a couple of times, and see if it varies much.
      You will get a measure for Download, Upload and Latency or "ping".

      Peter VK4IU

      --- In dxatlas_group@yahoogroups.com, "Dave" <dave@...> wrote:
      >
      > Hi Peter- High speed full-time Comcast Business service, static IP,
      > dedicated 2.6Ghz PC with 1Gb RAM, running Faros and no other apps.
      >
      >
      > Dave
      > DM78qg // KA0SWT
      > /++++++++++++++++++++++++++++++++/
      >
      >
      >
      >
      >
      > -----Original Message-----
      > From: dxatlas_group@yahoogroups.com
      > [mailto:dxatlas_group@yahoogroups.com]
      > On Behalf Of vk4iu
      > Sent: Tuesday, November 17, 2009 20:30
      > To: dxatlas_group@yahoogroups.com
      > Subject: [dxatlas] Re: Timing Question
      >
      > Dave,
      >
      > With so much Internet access variability across the world, there will
      > never be a single Internet source that will give a good result for all
      > - that is why there are hundreds of NTP time servers across the
      > Internet - spread all around the world. With a large population of
      > Time Servers there will always be a few time servers accessible anywhere.
      >
      > The question is still, can you get to the Internet in an adequate form
      > to retrieve time that meets the needs of Faros. Only you can answer
      > that question, by testing your connection. But, we can help you do
      > the tests to find out.
      >
      > The best approach is to divide your problem up. Lets work on one
      > thing at a time - forget the beacons for the moment. First - the Internet
      connection.
      >
      > What type of Internet connection do you have?
      > How fast is it?
      > Is it connected all the time?
      >
      > Peter VK4IU
      >
      >
      >
      > --- In dxatlas_group@yahoogroups.com, "Dave" <dave@> wrote:
      > >
      > > Hi to you too Peter! Nice hearing from you again. Yep, Faros is a
      > > good program but *somehow* timing has to be addressed. I'll look at
      > > the references in your email but I hope Alex can help some too. I
      > > can't believe I only 'see' one beacon a few times a day back-to-back
      > > time
      > slots.
      > >
      > > Timing is the issue I think -and my Faros also hears but does not
      > > record loud signals- with Faros and solving it will add a lot to the
      > > system overall. I was wondering if we all sync to a single source if
      > > it would help... Then again the transmitters all have their own
      > > timing patterns, so unless we ALL go onto one single time server
      > > we'll all be different. Gotta be a GPS solution here somewhere.
      > >
      > > Good stuff at Dave Taylor's site.
      > >
      > > Let's keep this thread going... Good stuff here.
      > >
      > >
      > > Dave
      > > DM78qg // KA0SWT
      > > /++++++++++++++++++++++++++++++++/
      > >
      > >
      > >
      > >
      > >
      > > -----Original Message-----
      > > From: dxatlas_group@yahoogroups.com
      > > [mailto:dxatlas_group@yahoogroups.com]
      > > On Behalf Of vk4iu
      > > Sent: Tuesday, November 17, 2009 15:53
      > > To: dxatlas_group@yahoogroups.com
      > > Subject: [dxatlas] Re: Timing Question
      > >
      > > G'Day Dave,
      > >
      > > I like your web site. I have a similar goal in mind - all of which
      > > came to a halt when I realised I was getting useless observations
      > > because of the problem of delivering stable time data to Faros. I
      > > hope you don't mind if I have a look at the Java on your pages.
      > >
      > > What are the problems caused by the ISP?
      > >
      > > For my journey through "time", I used the the usual ntpd NTP Time
      > > Server software and drivers on both Ubuntu Linux 9.04 Desktop and
      > > 8.10 Server, installing from the standard "package management" using
      > > Synaptic. On Windows XP, I used a port of the same software from
      > > Meinberg - http://www.meinberg.de/english/sw/ntp.htm - and
      > > Meinberg's NTP Time Server Monitor to observe and plot the
      > > statistics from all the
      > ntpd servers.
      > >
      > > I used many, and varied Internet time servers, and also connected my
      > > Garmin eTrex Vista GPS via a serial port to the Meinberg software on
      > > Windows, using the NMEA data strings only - the eTrex has no PPS output.
      > >
      > > It was all a very good learning experience, but with a lot of
      > > frustrations - all with "the time", and my Internet connection. The
      > > actual software installations were relatively simple and straight
      > > forward. One could describe the experience like big game hunting -
      > > hours and hours of observation and "taking aim", with the actual
      > > result occuring in just a minute or two. It is the sort of thing one
      > > has to do, to really understand what is happening with time and how
      > > it
      > affects the Faros observations.
      > >
      > > I went through the usual careful steps - got the radio-PC connection
      > > to work with OmniRig, checked for reasonable signals from all the
      > > beacons one could expect, then I simply fired up Faros. Initially,
      > > I selected a few time servers from the list and observed what
      > > happened over a day or so. The "dots" on the detail page were all
      > > over the place, and the UTC Clock accuracy "red line" went all over the
      place.
      > > Next I updated the TimeServer.lst with the usual "pool" of servers
      > > for Australia - see www.pool.ntp.org. For the UK they would be
      > > things like
      > 0.uk.pool.ntp.org.
      > > I got the same result - dots all over the place.
      > >
      > > That's when I implemented my own time servers.
      > >
      > > That gave me a reasonably straight line for the red "Faros time" in
      > > UTC Clock Info, Clock Accuracy. But the Faros observations on the
      > > Details panel went on a "roller coaster ride" day after day - the
      > > line of "dots" for beacon observations varying by 80-90ms over the day.
      > > The coloured blocks on the History page looked wonderful, but the
      > > data behind them was rubbish. I sat and watched the Monitor page
      > > for hours
      > > - time and again I watched Faros totally ignore nice strong beacon
      > > signals. Faros ended up following my time servers, which in turn
      > > followed the Internet time. Faros followed my servers because they
      > > were the fastest in terms of packet delay, and time variation. But,
      > > over many hours my time servers followed a large sine curve, with
      > > the 15
      > minute panel in the Clock Accuracy looking very flat.
      > >
      > > A last act, which has proven reasonably successful so far, was to
      > > decommission my time servers, but trawl through their logs and find
      > > the servers that were used for long periods of time as the reference.
      > > I then did ping tests, and trace routes on them, to find the closest
      > > and fastest 10 servers. I now have reasonable, straight lines of
      > > dots on the Details panel, and good SP/LP observations with no "missed"
      > observations by Faros.
      > > But ... I really don't expect it to last, and I certainly expect it
      > > to vary somewhat. I think it is good enough for casual use, but not
      > > enough for propagation studies, or good radio contest planning.
      > >
      > > The observations from the Garmin eTrex NEMA strings were useless -
      > > most of the Internet servers had less variation in time.
      > >
      > > In summary, my conclusions.
      > >
      > > My "broadband wireless" Internet connection is far too variable in
      > > terms
      > of
      > > "packet delay" for good time keeping at the precision needed by Faros.
      > Its
      > > nice and fast under normal use, but not good enough for time
      > > keeping, at the accuracy we need for Faros. The packet delay is
      > > mostly in the "wireless link", but add that variability to the
      > > variability of the Internet as a whole, the Internet time server
      > > load and subsequent variability, and finally, the use of the
      > > connection by other people and devices in my household - and Faros
      cannot "keep time" well enough.
      > >
      > > A NEMA strings based "consumer" GPS is not good enough - much too
      > > variable for the accuracy we need for Faros. I will report whether
      > > a "good" GPS can do it - see below.
      > >
      > > A "wired" ADSL or cable Internet connection may be good enough,
      > > provided the connection is stable in packet delay - that is, not
      > > overloaded by other uses in your household, or the network between
      > > you and the time servers. Only good time server selection, and
      > > rigorous observation over time will show whether or not the
      > > connection is adequate
      > for serious use with Faros.
      > >
      > > My current plan.
      > >
      > > I initially dismissed creating a stratum 0 reference time server -
      > > the Meinberg PCI card is priced at $3500 in Australia. But ...
      > >
      > > Alex VE3NEA alerted me to the following web site http://time.qnan.org
      > > I have ordered a Garmin 18x LVS, $100 n Australia, and I will
      > > proceed to integrate it into my Linux server. On that site there is
      > > a reference to http://www.satsignal.eu/ntp/index.html which is a
      > > fantastic source of information relevant to getting Faros a good
      > > time signal. I have high hopes of having a fantastic Faros
      > > installation for propagation study, site and antenna comparisons.
      > >
      > > Peter VK4IU
      > >
      > >
      > > --- In dxatlas_group@yahoogroups.com, "Dave Baxter" <dave@> wrote:
      > > >
      > > > Hi...
      > > >
      > > > I'm the guy who created the IC-PCR1000 "helper" app, so it can be
      > > > used with Faros/Omni-Rig. I did test it here before letting Dave
      > > > M have a copy, and AFIK no timing issues, but I stand to be
      > > > corrected on that if any are found directly attributed to that program
      of mine.
      > > >
      > > > I do agree with Peter, try things with a rig that is directly
      > > > supported by Omni-Rig first, just in case.
      > > >
      > > > Question for Peter. What software, program, tool, etc, did you try
      when
      > > > you tried a local GPS driven NTP server of your own? Did the
      > > > GPS/Server use a 1PPS signal, or just the NMEA data from the GPS?
      > > >
      > > > Curious....
      > > >
      > > > Regards to All.
      > > >
      > > > Dave G0WBX.
      > > >
      > > > PS: My Faros status page, all working from an old Icom IC-R70,
      > > > and another of my own programs to glue it all toghether.
      > > > http://g8kbv.homeip.net:8008/
      > > >
      > > > Yes, I too have some NTP issues, but caused by my ISP.
      > > >
      > >
      > >
      > >
      > >
      > > ------------------------------------
      > >
      > > Yahoo! Groups Links
      > >
      > >
      > >
      > >
      > > ----------
      > >
      > >
      > > No virus found in this outgoing message.
      > > Checked by AVG - www.avg.com
      > > Version: 8.5.425 / Virus Database: 270.14.68/2507 - Release Date:
      > > 11/16/09 19:53:00
      > >
      > >
      > > [Non-text portions of this message have been removed]
      > >
      >
      >
      >
      >
      > ------------------------------------
      >
      > Yahoo! Groups Links
      >
      >
      >
      >
      > ----------
      >
      >
      > No virus found in this outgoing message.
      > Checked by AVG - www.avg.com
      > Version: 8.5.425 / Virus Database: 270.14.71/2510 - Release Date:
      > 11/17/09 19:26:00
      >
      >
      > [Non-text portions of this message have been removed]
      >




      ------------------------------------

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      ----------


      No virus found in this outgoing message.
      Checked by AVG - www.avg.com
      Version: 8.5.425 / Virus Database: 270.14.71/2510 - Release Date: 11/17/09 19:26:00


      [Non-text portions of this message have been removed]
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