TRG vs GPS Statistics of Dec. 2002 test run


Plots of data from 12-19-2002 03:28:59 to 12-24-2002 23:59:59


Relative time between spills (via TRG 48-bit clock)



same as above, but zoomed in [2.17 ... 2.21] and with histogram


TRG oscillator drift from 50 MHz (*1)


Absolute spill time difference between GPS1 and GPS2


Relative spill time difference between GPS1 and TRG (*2)


Relative spill time difference between GPS2 and TRG (*2)


Histograms

Note: y axis is log scale


Notes

(*1)   Both, the TRG module and LTC module each use an internal, free-running 50 MHz crystal oscillator (independent) for their clock counters. The two oscillators are not temperature compensated! Therefore, any change of the room temperature in the North Hall control room causes them to drift. Cooler temperatures usually result in higher frquencies than at warmer temperatures.
(*2)   Absolute TRG clock vs. GPS time measurements cannot be made due to the mentioned temperature-dependent TRG oscillator drifts, as shown in the wave forms of the plots above. The waves are inverse proportional to temperature changes in the North Hall.


See also list of errors.