[time-nuts] TIC resolution impact on GPSDO's performance

[Poul-Henning Kamp]

In message <459054DC.8030701 at xtra.co.nz>, Dr Bruce Griffiths writes:

>> A quantum of 1ns is not a concern if the attack point for the PLL
>> is on the order of hours.
>>   
>This statement is only true when one is disciplining or monitoring 
>relatively with sufficiently large frequency and/or phase instabilities.
>When one wishes to discipline an Oscilloquartz 8607 OCXO for example 
>every nanosecond or fraction thereof matters.

As far as I can see on TVB's site, the 8607 is about 5e-13 at 1000 sec,
so 1ns/1h sounds perfectly good to me.

>Its not the coherence of the sawtooth but the coherence between the 
>oscillator clocking the timer used to position the PPS signal and the 
>frequency of the PPS signal itself.

Yes, those are non-coherent, that is why we need the negative sawtooth
in the first place.  If they were coherent, we could just have
used a formula.

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