Richard (Rick) Karlquist
richard at karlquist.com
Thu Aug 30 03:45:02 UTC 2012
On 8/27/2012 11:45 PM, WB6BNQ wrote:
> A microprocessor controlled XO is a non oven crystal oscillator system that has
> additional computational control providing a bit more than just mere passive
> temperature compensation. The additional computational capability deals with
> having coefficients of that particular oscillator's behavior pre coded to
> compensate for the nonlinear behavior over a given temperature rang
It doesn't use coefficients. It has a look up table of frequency vs
> A microprocessor controlled XO system allows for using cheap crystals with
> minimum processing time and costs. Because of limited storage space there is no
No it doesn't use a cheap crystal. It uses a *special* SC cut crystal.
This crystal could very easily cost more than an OCXO crystal.
> way for the system to have enough data to even try to compete with the quality of
> a decent OCXO. Beyond its initial calibration setup, it has no way of keeping it
> tied to a known reference, like the Thunderbolt is doing.
An MCXO is a very good, but expensive TCXO. Only temperature, not aging
It has nothing to do with "smart clocks".
Rick Karlquist N6RK
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