jherrero at hvsistemas.es
Fri Aug 31 07:49:14 UTC 2012
El 30/08/2012 20:53, SAIDJACK at aol.com escribió:
> There are some drawbacks to this type of SC-cut MCXO I would think, and it
> could possibly be replaced by a much higher performance Symmetricom CSAC,
> probably at a lower cost and higher availability:
> * Q-tech MCXO is ITAR controlled, CSAC is not
> * MCXO has 20ppb over temp stability, CSAC has 1ppb spec, typical units can
> be much lower than that. Our GPSTCXO has 75ppb over temp, not much more
> than the MCXO, but probably at 1/10th the cost.
> * The G-sensitivity of CSAC is at least 50x better than the MCXO (its so
> low, its very hard to measure)
> * Aging of MCXO is much higher (order of magnitude)
> * Symmetricom is a big player, Q-tech is relatively small and unknown
> * I remember that there are patents on the MCXO held by FEI?
> * Power consumption is very similar, future CSAC units will have much lower
> power than the MCXO.
> The MCXO does have lower phase noise, it's an SC-cut cyrstal after all. But
> with CSAC's now becoming available from multiple sources, why use an MCXO?
As you say about G-sensitivity, let time pass until the CSAC is also
ITAR controlled ;) It will no take too much.
More information about the Time-nuts_lists.febo.com