[ntp:questions] ntp-4.2.6p5 on Win 7 x64

jimp at specsol.spam.sux.com jimp at specsol.spam.sux.com
Sat Jul 19 17:09:19 UTC 2014


Nick <me at privacy.net> wrote:
> On Fri, 18 Jul 2014 23:16:57 +0000, jimp wrote:
> 
>> Nick <me at privacy.net> wrote:
>> 
>> <snip>
>> 
>>> This performance is marginal for WSJTX.  I need 10ms offset or less
>>> after 15 minutes.
>> 
>> What make you think that?
>> 
>> I see a lot of WSJTX signals that are within +/- .5 seconds and
>> occasionally some over a second off and they still decode. Most seem to
>> be +/- .3 seconds.
>> 
>> We are talking about this aren't we:
>> 
>> http://physics.princeton.edu/pulsar/K1JT/wsjtx.html
>> 
> 
> Yes we are.
> 
> My spec was based only on experience using JT65B on HF using the old XP 
> box which easily syncs within 10ms, and on which decodes are rock solid.
> 
> http://www.vhfdx.de/wsjt/wsjt_user_470.pdf says...
> 
> "You will need a method of setting your computer clock to an accuracy of 
> one second or better, and keeping it set. Many operators use an internet 
> clock-setting program, while others use a GPS or WWVB receiver."
> 
> Thank you for helping me realise the extent of my own ignorance!
> 
>> Though I agree ntp should be doing a lot better than you are seeing.
> 
> Yes.  I'll keep digging.

FWIW, the largest offset I've seen WSJT-X decode is 3.5 seconds and lots
of DX stations are in the 1 to 2 second range.

BTW, if you are not using it, JT-utilities is very handy.

http://hamapps.com/


-- 
Jim Pennino



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