[Elecraft] Time Syncronization

[Walter Underwood]

A good NTP implementation is awesome technology. It was awesome more than 25 years ago. As an example, here is my second open source contribution, from 1993. Not sure why the first search hit is from Apple, but whatever.

https://opensource.apple.com/source/ntp/ntp-92.30.1/scripts/ntp-groper.auto.html <https://opensource.apple.com/source/ntp/ntp-92.30.1/scripts/ntp-groper.auto.html>

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

> On Sep 13, 2017, at 5:03 PM, Lynn W. Taylor, WB6UUT <KX3.1 at ColdRocksHotBrooms.com> wrote:
> 
> Again, my statement is that keeping good time is not difficult.
> 
> A good NTP client will do that.
> 
> Yes, I do realize that if your clock is 20 milliseconds fast, and the other guy is 20 milliseconds slow, the total error is 40 milliseconds.
> 
> The documentation at <http://physics.princeton.edu/pulsar/K1JT/wsjtx-doc/wsjtx-main-1.7.0.html#SYSREQ> does say plus or minus 1 second.
> 
> It then goes on to recommend a couple of good NTP clients (which have been mentioned here) that will do several orders of magnitude better than that.
> 
> 73 -- Lynn
> 
> On 9/13/2017 2:40 PM, Jim Brown wrote:
>> Lynn,
>> You can argue all you like, but those with long experience with WSJT modes try to keep their clock within a few tens of msec of correct time. Why?  Because the other station can be off in the other direction, and what counts is the DIFFERENCE between you and the station you're trying to work. And the greater that difference, the less likely that you will decode each other, especially under weak signal conditions. Why? Because the noise reduction schemes for JT65, JT9, and FT8 are synchronized to the beginning of the transmission period, and the decoding station needs to lock onto the sending station.
>> Time sync is LESS critical for modes like MSK144 and ISCAT, which are primarily used for meteor scatter, decode from short bursts of signal, and do not depend on sync for their decoding.
>> 73, Jim K9YC
>> On 9/13/2017 1:38 PM, Lynn W. Taylor, WB6UUT wrote:
>>> Plus or minus 500 msec. isn't a big deal.  It's big enough that I'd argue that it's essentially the same.
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Elecraft at mailman.qth.net
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to kx3.1 at coldrockshotbrooms.com
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to wunder at wunderwood.org