[time-nuts] femtosecond jitter anyone?

[Chris Mack / N1SKY]

On Apr 8, 2009, at 8:02 PM, Bruce Griffiths wrote:


> Unless you are prepared to place the crystals in an oven with the
> temperature regulated tightly and carefully tune the filter  
> periodically
> then using a crystal filter (or any passive filter with a sufficiently
> narrow bandwidth to cleanup the skirts) will not be particularly  
> useful.
> It would be much easier to use a low bandwidth analog PLL with a low
> noise VCXO to cleanup the 38.88MHz signal.
>

http://www.national.com/pf/LM/LMK04000B.html

Their app note uses a very low noise VCXO...  The simulator software  
gets pretty close...

Cheers,
-chris