[time-nuts] Time servers on a well known web site.

Dave Baxter dave at uk-ar.co.uk
Thu Jul 9 17:08:50 UTC 2009


Yes Chris, I did notice that.   ("red herring" that is)

But I also do know that many people do indeed put various flavours of
Linux etc on the "Slugs" as they are known, for all sorts of odd
purposes.  So (subject to enough memory) I suspect they could do the
job, somehow.  What that was advertised to be, I have no doubt it can be
done.  Just as before, without the 1PPS input, the actual accuracy (as
in +- mS of UTC) would not be good.  But for an unconnected (to the
outside world) network that doesnt need mS accuracy to UTC, they could
provide an acceptable NTP source perhaps to keep a collection of file
servers in sync, or to drive time of day displays.

Some of the earlier Linksys WRTG routers are also popular targets for
home brewed Linux based "appliances", and there is also a lot of
information about regarding hacking the hardware to include a "real"
serial port too.  (Seems, the only parts missing are the RS232 line
drivers, and the 9way D socket!) It's a pity that the availability of
the early versions that will run Linux etc, are becoming less common.

With cheap second hand hardware like that about, with the right tools
and information, I don't see it as impossible to re-purpose what was a
Router, to be a GPS Disciplined NTP server, or anything else for that
matter.  People are already using them as Packet Radio (APRS)
digipeaters & Igates etc.

Then there are the proliferation of single board router kits about, at
has to be said a good cost with amazing processing capabilities, and
fast network ports.  Many interestingly from Eastern Europe!   Any of
them use a fraction of the power a PC needs.

I did (out of curiosity) look up an early RFC regarding the NTP protocol
itself.  After my head had stopped spinning, I couldnt help wondering
that with modern micro-controllers, some of which have "open licensed"
TCP stacks available.  One of them could do the job, subject to the
software being brewed of course.

As to the rack units, not a lot of use to me then, even if I could
afford them.

Me.  I just need the time to mess with all this...   At the moment, my
ISP's NTP service seems to be ticking along OK, but I would not be
suprised to see it to jump sideways again, at any time without warning,
as they are currently "restructuring" their own network.

Cheers All.

Off home now.

Dave B



Message: 8
Date: Thu, 9 Jul 2009 09:54:12 -0600
From: Chris Kuethe <chris.kuethe at gmail.com>
Subject: Re: [time-nuts] Time servers on a well known web site.
To: Discussion of precise time and frequency measurement
	<time-nuts at febo.com>

Message-ID:
	<91981b3e0907090854v54af33d4v31fd6d184f3ade7 at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

On Thu, Jul 9, 2009 at 7:17 AM, Dave Baxter<dave at uk-ar.co.uk> wrote:
> Just found these on eBlag.
>
> Way outside my price range, but...
>
> 220445049656 ? Not sure if it actualy does GPS disiplined stuff, as
there is no GPS antenna socket!
>
> 180370118043 ? Still too rich for me. ?And when you consider even a
new NSLUG is about ?65, and the GPS is not an expensive item either,
plus the software is probably 'nix based.

did you notice that the demo site is called "red herring" - something is
fishy about this whole setup.

> I hope the guy selling them, is whoever has worked out how to do that.
? I'd hate to think somone else has put a lot of time and effort into
doing that, and is getting ripped off. ? Wonder too just how accurate it
is, using a USB based (non PPS) GPS?

>From the product's webpage: "The NTS1-GPS time source provides a time
reference derived from the reception of NMEA data from the USB GPS
receiver. It does not contain a pulse-per-second (PPS) kernel nor
high-stability oscillators. The NTS1-GPS is not designed nor intended
for use in application where high-precision high-stability UTC time is
required. Position information is provided by the NTS1-GPS for reference
only"

>
> Cheers All.
>
> Dave B
> G0WBX.




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