Magnus Danielson wrote: > From: Brooke Clarke <[EMAIL PROTECTED]> > Subject: Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit > Date: Tue, 19 Dec 2006 13:42:28 -0800 > Message-ID: <[EMAIL PROTECTED]> > > >> Hi Brendan: >> >> It's interesting that the PRS10 can time stamp the 1 PPS input with a >> resolution of 10 ns. I wonder how they do that. >> http://www.thinksrs.com/downloads/PDFs/Catalog/PRS10c.pdf >> > > It actually says it does it with 1 ns resolution. A x100 analog interpolator > circuit for 1 ns to 100 ns (10 MHz) isn't rocket science. See the HP 5335A > operations and service manual. Getting 10 ns accuracy isn't supprising. > > >> When I picked up my PRS10 at the factory during the tour I learned that >> the 10 MHz oscillator in the PRS10 was an improved version of the SC10. >> There's an Allan plot for the PRS10 at: >> http://www.thinksrs.com/products/PRS10.htm <- overall PRS10 page >> http://www.thinksrs.com/assets/instr/PRS10/PRS10diag2.htm <- Just the plot >> > > Do the PRS10 comes with the 5 dollar tour ticket or is it the other way > around? > :D > > The PRS10 seems like a good device. > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list > [email protected] > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > The PRS10 is somewhat marginal for VLBI although it has been used for short integration times to observe the L band hydroxyl line at around 1600 MHz. Fortunately all stations but one used hydrogen maser clocks/frequency standards. Some of the better crystal oscillators (Oscilloquartz 8607 BVA, FTS1200 etc) have better performance for integration times up to 100s or so. The PRS10 OCXO DAC has a fractional frequency resolution of around 1E-12. This limits its performance for VLBI with long integration times where it is necessary to have phase synchronisation between all stations to within 10 degrees or so over the integration time.
Bruce _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
