[time-nuts] Software Sawtooth correction prerequisites?

[Dr Bruce Griffiths]

Hal Murray wrote:
>> Synchronisers can easily be built from shift registers.
>>     
>
> What do you mean by "synchronizer"?
>
> Are you talking about a delay so the times line up correctly or a 
> circuit to avoid metastability?
>
>
>   
Hal

Usually just a fast shift register with the number of stages selected to 
achieve a suitably low rate of metastable states at the output.
Its usually easy to ensure that the failure rate is less than once in a 
few terayears.
The PPS signal will not be synchronous with the local OCXO due to noise 
and sawtooth error so that metastable states are possible when the PPS 
is connected to the D input of a flipflop clocked by the OCXO.

Bruce