Yes, you can assume df for a Cs or GPS is zero for all but short time spans.
/tvb ----- Original Message ----- From: Brooke Clarke To: Tom Van Baak ; Discussion of precise time and frequency measurement Sent: Saturday, April 09, 2005 15:48 Subject: Re: [time-nuts] Frequency error -> Parabolic Time Error? Hi Tom: Now suppose the reference oscillator is a Cesium type, does that automatically mean that df is zero? Have Fun, Brooke Tom Van Baak wrote: Yes, the curve is described by a quadratic formula, same as any parabola. The time, T, (phase) of a reference oscillator is given by: T = t0 + f0 * t + 1/2 * df * t^2. -- where t0 is the initial time offset (phase), -- and f0 is the initial frequency offset, -- and df is the frequency drift per unit time. This can give rise to several different looking shapes depending on the initial conditions. /tvb ----- Original Message ----- From: "Brooke Clarke" <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" <[email protected]> Sent: Saturday, April 09, 2005 15:18 Subject: [time-nuts] Frequency error -> Parabolic Time Error? Hi: Suppose that my reference oscillator is offset from 10.0 MHz by some small amount. If I plot the time interval between the reference oscillator and a GPS 1 PPS what will the plot look like over a long time period, a parabola? Have Fun, Brooke -- w/Java http://www.PRC68.com w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml http://www.precisionclock.com _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts -- w/Java http://www.PRC68.com w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml http://www.precisionclock.com _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
