[ntp:questions] fudge time1 for gps-18x-LVC?

Rob nomail at example.com
Sat Feb 6 14:09:48 UTC 2010

David J Taylor <david-taylor at blueyonder.delete-this-bit.and-this-part.co.uk.invalid> wrote:
> "David Woolley" <david at ex.djwhome.demon.invalid> wrote in message 
> news:hkjre8$7b3$1 at news.eternal-september.org...
>> David J Taylor wrote:
>>> OK, I mis-read the table.  If the 9 microseconds is the true offset,
>> What do you mean by true offset?  That is not actually measurable
> As opposed to the figures of 350 microseconds, 350 milliseconds, and 650 
> milliseconds which had also been mentioned, and the 21 millisecond figure 
> in the table.

Yes the story sure is confusing.  I am not at all amazed by NMEA offsets
that are a big fraction of a second, and that are varying.  But in this
story, it seems that the same number is rarely mentioned twice.

It is quite normal that once stability is achieved, the PPS source has
a very low offset and the NMEA source has quite a high offset, that could
be enough to lose lock when there is no suitable fixed offset applied.

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