Hi Mark,

> Interesting... what happened on day 4 to send them all bonkers?

What you see as bonkers starting the 5th day is actually normal behavior for a 
cesium clock (or any clock, for that matter). I mention this plot because it 
shows that you cannot get 500 ps over a day, even with a 5071A -- which is why 
we're all trying to help the OP with alternative methods of time 
synchronization.

There are several ways to plot phase data. What people often do is plot 
residuals for the entire data set. That is, showing how good the clock would 
have kept time *if you knew ahead of time what the rate would be*. The first 5 
days of the plot shows the residuals based on 5 days of rate fitting. At that 
point the calculated rate was fixed and the clocks continued to tick. So it 
becomes a 10-day plot of phase residuals based on 5 days of fitting. I like 
this because it more dramatically shows how hard it is to keep accurate time.

The spread in phase is expected. In fact this spread is what ADEV measures; 
variations in frequency accumulate to phase drift. Or vice versa: erratic drift 
in phase is evidence of frequency instability, which in turn is summarized with 
ADEV statistics. I know I'm not explaining this well enough, and it's a bit 
off-topic for this thread, but I'll write it up later and post it.

/tvb


----- Original Message ----- 
From: "Mark Sims" <[email protected]>
To: <[email protected]>
Sent: Wednesday, May 04, 2016 4:41 PM
Subject: [time-nuts] Fw: Optical transfer of time and frequency


>> See www.leapsecond.com/tmp/5071a-12-run8-5d-10d.gif for a plot of a bunch of 
>> 5071A Cs clocks.
> Interesting... what happened on day 4 to send them all bonkers?
> 

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