[ntp:questions] help with setting up NTP on windows with a USB GPS

David Lord snews at lordynet.org
Fri Dec 4 18:09:38 UTC 2009

David J Taylor wrote:
> "Dave Baxter" <spam at goes.nowhere.com> wrote in message 
> news:MPG.2582f2d76a9bb78e989699 at news.btopenworld.com...
> []
>> Hi...
>> First, thanks for the direct email, I'll look at things in detail again
>> this evening/over the weekend.
> []
>> Your sumizing above, is exactly what I'd like to do, idealy all on one
>> physical box if posible.  But as elsewhere, I'm not haveing much success
>> stitching it all together on a box of its own at present.   The latest
>> being that the 'Reg' command, usd by Dave Hart's serialpps install batch
>> file, does not exist on Win2k!  (XP and later only I think.)  Oh well.
> []
>> Regards to all, and thanks for being tolerant.
>> Dave Baxter.
> Dave,
> As I mentioned in the private e-mail, I suggest you don't bother with 
> the PPS DLL stuff until after everything else is working, because when I 
> tested it although you could see a noticeable improvement in the jitter 
> level as reported by NTP, the offsets seemed to be very similar with and 
> without the kernel-mode stuff.  See:
>  http://www.satsignal.eu/ntp/NTP-on-Windows-serial-port.html#PPSAPI_DLLS
> I accept that if the system was more heavily loaded the results might be 
> different, though.

Not windows but on NetBSD with a good radioclock MSF signal via
serial port I was a little better with pps, but when moved to
location where signal isn't so good, with pps is a lot worse than
without. Currently I'm trying mindist 0.003 without pps and that
seems to be a slight improvement, but temperature changes, or
lack of, might be involved. When MSF Tx is down on 10th, or next
network outage, I'll swap back to using pps and hope the mindist
change will result in keeping to pps rather than periodic swap
between pps and radioclock source (from logs it looks as if 3ms
is way more than enough whilst 1ms was just on edge).


> Hope the head cold soon clears!
> 73,
> David

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