Magnus Danielson wrote: > From: [EMAIL PROTECTED] > Subject: Re: [time-nuts] On some pitfalls of the dual mixer time > differencemethod of h... > Date: Sun, 1 Oct 2006 13:53:57 EDT > Message-ID: <[EMAIL PROTECTED]> > > >> Hello Ulrich, >> > > Ulrich and Said, > > >> the latest generation of TSC intruments (the TSC5120A for example) uses a >> new strategy: they use four ADC's to sample and cross-correlate two >> oscillators >> completely in software. All the mixing etc is done in the software domain. >> That makes for cheap hardware, and works quite well. They had a tutorial >> about >> this at this years UFFC in Miami. >> > > You also get some insight when picking up the manuals from their web. It is a > quite different animal in implementation than the old hardware correlatetors > are, which has both benefits and drawbacks. It is however a very modern > approach indeed. > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > Interesting as the techniques employed may be, the resultant performance is still inadequate for characterising state of the art oscillators. The instrument phase noise floor is higher than that specified for current low noise (but not necessarily low drift) crystal oscillators.
The Allan deviation of current state of the art cryogenic sapphire oscillators is more than an order of magnitude lower than the noise floor of these instruments. Bruce _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
