[time-nuts] Question on crystal jumps

Joseph M Gwinn gwinn at raytheon.com
Thu Oct 23 23:57:44 UTC 2008


Would SAW oscillators be better than crystals?

Joe


time-nuts-bounces at febo.com wrote on 10/23/2008 07:01:31 PM:

> Steve Rooke wrote:
> > Hi,
> >
> > I believe it was pointed out earlier that the output of a LPRO uses
> > some form of xtal oscillator as the output of the rubidium stage is
> > quite noisy. Considering the general consensus is that xtal
> > oscillators have these jumps, I wonder if the output of the rubidium
> > stage could be just passed directly through a multi-stage xtal lattice
> > filter to clean it up and use that directly and that may circumvent
> > the xtal jumps people are seeing.
> >
> > 73 - steve
> > 
> Steve
> 
> The rubidium standard is passive it doesnt oscillate, it merely acts as
> a high Q filter whose resonance can be probed with an external source.
> Thus you need to replace the crystal oscillator with another low noise
> source to interrogate the rubidium resonance.
> 
> To be useful the bandpass filter would need a bandwidth of a few
> milliHertz or less.
> The crystals in the lattice filter will also experience similar jumps.
> 
> Bruce
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-
> bin/mailman/listinfo/time-nuts
> and follow the instructions there.




More information about the time-nuts mailing list