[time-nuts] GLONASS receiver

mike cook mc235960 at gmail.com
Sun Aug 5 19:23:27 EDT 2012


Le 06/08/2012 00:01, Bob Camp a écrit :
> Hi
>
> The part at the link does not appear to have a holdover specification. You probably would do better with a TBolt off of eBay.
Agreed.
  I took a look at the Axtal AXIOM40 data sheet and they are quoting 200 
ppb per YEAR aging.. That's not bad; so if the device is only affected 
by that in holdover, it's only 200ns slow out at the end of a year ... I 
doubt that my T-Bolt could do as well. So as to providing a stable 
frequency it looks fine. HOWEVER that particular device has1PPS on the 
DCD line FROM the GPS receiver and not disciplined by the OCXO, so the 
advantage is lost and the PPS will drift at the receivers onboard 
crystal aging rate while not getting updates from GPS.  So it's not a 
good choice. Better to get a device with PPS disciplined directly by the 
main oscillator and aligned to UTC when  the signal is available as in a 
T-Bolt.

-- 
Les chiens aboient, et la caravane passe.





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