> -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Matt Ettus > Sent: Monday, January 05, 2009 11:31 AM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Common sky pps errors for any GPSDOs? > > I am working with someone who needs to have time synchronized > reception of signals in various locations which are separated > by less than 100 km. This is a situation similar to VLBI, > but since the distances are shorter, the center frequencies > are lower, and the integration times are much shorter, we > probably don't need a Hydrogen Maser, and the application > can't afford one. > > The real question is whether we can get away with a GPS > disciplined OCXO or whether we would need to use a Rubidium. > Does anyone have any data on the relative frequency and/or > phase errors of the 10 MHz reference out, and relative PPS > time errors of any commonly available GPSDOs?
Isn't that just the Allan Deviation data? Symmetricom has datasheets on their website for their various modules. They have a GPS discplined quartz oscillator in several flavors. http://www.symmetricom.com/media/files/downloads/product-datasheets/ds%20XLi%20Options%202.pdf Something else to consider is doing post processing.. Use a nice quiet 10MHz oscillator for your source/sampling clock, and record the 1PPS from the GPS receiver as well as your unknown, then figure out after the fact what the oscillator was doing. Jim _______________________________________________ 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.
