Hi No, there is no purely analog way to access the sawtooth information. If you restrict yourself to “pure analog” then the PPS will be bopping around by +/- 10 to +/-20 ns each second. Put another way, you start out with 1 to 2x10^-8 at 1 second. The same thing is true at 10 KHz or at any other output frequency.
To get down to the vicinity of 1x10^-10 with any sort of rational ADEV, you are going to need the equivalent of a very long time constant analog filter. It also needs to have *very* good DC characteristics and low noise. The simple answer is to use a *lot* of C and not much R in the beast. That gets you into a boatload of high quality film capacitors. There is no getting around having a narrow / long time constant filter if you want a useful signal out of the OCXO... Bob > On May 22, 2016, at 8:24 PM, Chris Albertson <[email protected]> > wrote: > > On Sun, May 22, 2016 at 3:52 PM, Attila Kinali <[email protected]> wrote: > >> Judging from the ADEV plots of the M12 receiver from TvB[1], which hit >> 10^-10 (w/ sawtooth) around 200s, I'd say that 10^-10 @1000s should be >> easy. > > Can a pure analog design access the sawtooth correction? My GPS > receivers send sawtooth as a digital message on a serial port. I > don't know if saw tooth correction is required to meet his spec. > > I think what he needs if he wants to go 100% analog is a GPS receiver > that outputs pulses at 10Hz not 1Hz. But to program the pulse rate > he'd need to send data to the serial control port. > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
