[aprssig] Looking for info on GPS clock synchronization

[Ben Jackson]

I'm looking for information about what clock information can be extracted
from a standard NMEA string.  For example, which moment during sentence
transmission is associated with the timestamp(s), whether GPS units that
only output 1s time resolution typically send sentences aligned to the
second, whether there's any spec for the baud timing accuracy, or the
start intervals of sentence groups.

Basically anything to can do with a GPS that doesn't have PPS output
to get into the 1-3ppm accuracy range.

-- 
Ben Jackson AD7GD
<ben at ben.com>
http://www.ben.com/