[time-nuts] U-blox teaser

[ed breya]

John, if you look back at the recent GPSDO discussion initiated by 
"dandober" in hpaligent keysight group, you'll see a post by Leo Bodnar, 
linking a Ublox model here

https://www.u-blox.com/sites/default/files/products/documents/LEA-M8F_DataSheet_%28UBX-14001772%29.pdf

I looked it up, and I recall the PPS timing spec is +/- 5 nSec. After I 
studied it some, I replied back

"Thanks Leo, that's a great example of what I've been picturing. This is 
from the data sheet, regarding the PPS output:

"After an initial phase of acquisition the time-pulse becomes 
essentially jitter-free, generated coherently from the built-in 
reference oscillator and guaranteeing an exact number of reference 
frequency cycles between each time-pulse."

It looks like this is an implementation of what we've talked about here 
before a few times, for saw-tooth error reduction. BTW I didn't call it 
"1PPS" above, because it can be programmed for different rates - I don't 
recall what they are.

BTW, did dandober ever sign up here?

Ed