[time-nuts] beautiful jump

SAIDJACK at aol.com SAIDJACK at aol.com
Sat Nov 1 00:56:11 UTC 2008


Hi Tom,
 
the fine dac on that unit has a 40mV range with hysteresis, the  coarsedac 
will not have been affected. I believe the 2.7mV change on the  large jump had 
an effect of approx. 2ppb frequency change.
 
The second jump of approx. 80 microvolts had only about 6E-011 change in  
frequency, that's enough to make the graph show a nice jump thanks to the GPS  
reference.
 
We need to keep in perspective just how small some of these jumps are, but  
even the small one still shows up as a 29ns deviation on the 1PPS lock..
 
bye,
Said
 
 
In a message dated 10/31/2008 17:31:15 Pacific Daylight Time,  
tvb at LeapSecond.com writes:

Also,  Said, can you tell from this unit's gpsstat if there is an
interaction  between the coarse and the fine DAC?

I see in the colima.htm file the  EFC went from 2.80299 to
2.80034. What the Hz/V for this unit? I.e., how  many ppb
was this  jump?

/tvb




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