[Elecraft] K3 Time

[Julian, G4ILO]

David Woolley (E.L) wrote:
> 
> 
> As this often causes confusion, it is worth pointing out that this is 
> not something written by Meinberg, but simply the reference 
> implementation of NTP, which Meinberg have compiled for Windows and to 
> which they have added an installer.  The reference implementation is the 
> definitive implementation that needs to be produced before an RFC can be 
> issued.  The NTP reference implementation is open source.
> 
>> NOAA satellite images and when using WSPR when you need better than one
>> second accuracy. This program runs as a service and after it has worked
>> out
>> the drift in your computer clock it applies constant millisecond
>> corrections
> 
> Technically it applies frequency corrections - NTP uses a PLL - it was 
> designed by an electronics engineer and ham.
> 
>> so it is spot on all the time. The time synchronizer built in to Windows
>> XP
> 
> Windows is a poor platform for time and, on most other platforms the 
> reference implementation gives even better time, although there is some 
> evidence that another open source implementation, chrony, that uses the 
> same over the wire formats but a different (linear regression based) 
> mathematical approach, has better behaviour for start up and temperature 
> change transients, in real world use.  However chrony is only supported 
> on Linux, and doesn't support local radio reference clocks.
> 
>> only syncs the clock once a week which may not be enough on some PCs.
> 
> The poll period is configurable, and the Windows 2003 version can be 
> configured to almost use the proper NTP algorithm.  The reference 
> implementation is still much better, as it uses various tricks to get 
> round the fact that Windows only reports time to applications with a 
> 10ms resolution, by default, or 1ms with the fastest multi-media timers.
> 
> I would generally ignore the non-open source alternatives as many are 
> very crude and none are better than the reference implementation, or
> chrony.
> 
> 

I agree with all of that, David. It might also be worth mentioning for the
benefit of those considering other alternatives that the last time I
recommended this to someone it was a VK ham who had apparently been blocked
from accessing his local NTP server because the non-open source software he
used polled it too often. Because the NTP software regulates the clock
itself it can get by with infrequent checks to the time server, even if the
computer clock is quite inaccurate.

-----
Julian, G4ILO. K2 #392  K3 #222.
http://www.g4ilo.com/ G4ILO's Shack    http://www.g4ilo.com/kcomm.html KComm
for Elecraft K2 and K3   http://www.wota.org.uk/ Wainwrights On The Air 

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