[time-nuts] Disciplining Rubidium

[SAIDJACK at aol.com]

Hi Antonio,
 
in my opinion the Rb in the chain gives you two distinct advantages (and a  
lot of drawbacks):
 
1) Warmup time. Rb's can warm up very quickly, much quicker than the  Crystal 
itself even under GPS discipline. This is especially so with new  Crystals, 
or long power-off times, or when the crystal experienced lot's of  mechanical 
stress/temperature changes etc.
 
2) Holdover capability during GPS outage. Every crystal will wander.  Rb will 
do so much less.
 
And maybe (in case of cheap oscillators) increasing the stability  of the 
crystal oscillator for average times of say 20s to a couple of  thousand seconds.
 
bye,
Said
 
 
In a message dated 4/23/2008 15:11:56 Pacific Daylight Time,  
iovane at inwind.it writes:

Does it  make any sense "GPS disciplining" a rubidium oscillator?
In such a case we  have a chain made of
GPS - Rubidium - XTAL
as opposed to the simpler  case of 
GPS - XTAL
(assume that XTALs are of the same quality, and so  the control loops).
Does the addition of Rb in the middle of the chain add  
any real advantages?

Antonio  I8IOV



_______________________________________________
time-nuts  mailing list -- time-nuts at febo.com
To unsubscribe, go to  https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the  instructions there.





**************Need a new ride? Check out the largest site for U.S. used car 
listings at AOL Autos.      
(http://autos.aol.com/used?NCID=aolcmp00300000002851)