[time-nuts] NEO-M8N vs. NEO-M8T
petervince1952 at gmail.com
Mon May 21 17:08:14 EDT 2018
On 21 May 2018 at 21:24, Mark Sims wrote:
> One thing to look out for when messing with sawtooth messages is the
question of does the message come
> out before or after the PPS pulse... good look finding the answer in the
> "After" seems to be the most common answer. That makes hardware/delay
line compensation rather tricky.
> Sometimes you can use the antenna cable delay / pps offset commands to
shift the pulse before the true
> position (assuming that they support negative offsets) and use a longer
delay line to add the tweak back in.
In the protocol specification for the Furuno GT-87
( from, for example:
the sawtooth correction figure is given in the CRX message, at the top of
page 30 of that document says the figure given refers to the second before
last (t-1) !
More information about the time-nuts