Does the longer time constant actually make a "better" frequency standard, or does it just push the noise from one frequency region to another? Has anybody with gear good enough to measure close in noise looked at the spectrum for different time constants?
Hal,
Last I checked - phase noise, as in L(f), is the same for all time constants. Frequency stability, as in sigma(tau), ADEV, etc. typically improves as the TC increases, out to 1000 s. The default of 100 s works pretty well for normal environments. But if your sat visibility and voltages and temperature and air currents and local seismic (vibration, shock, kids playing, doors closing, etc.) environment is unusually stable then you could bump the TC beyond 100, maybe even near 1000. I run my best TBolts closer to 300. For some time constant plots, see: http://www.leapsecond.com/pages/tbolt-tc/ /tvb _______________________________________________ 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.
