euclid The Time Traveler's Clock, Руководство пользователя

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must calculate the actual current time using the rate error and the number of days since
the chronometer was set to correct time.
The TTC contains a servo mechanism which provides a mechanical twisting motion to
the chronometer once per second to keep the chronometer synchronized with the GPS
timing receiver (which in turn is stabilized by the cesium CSAC). Thus, the GPS clock, the
cesium frequency reference, and the Hamilton chronometer are kept in resonance, and
the chronometer will remain as accurate as the GPS and atomic references.
The Hamilton 21 chronometer in the TTC is equipped with an electronic winding system
that winds the chronometer each hour to a consistent state of winding.
In order that precise time could be calculated from the Hamilton chronometer even if
the GPS and atomic references are not functioning (for example, if electrical power has
been lost for longer than the backup batteries will maintain operation), the natural rate
of the chronometer is measured once per day for a period of thirty minutes (at
midnight), and the deviation of the mechanical clock from the GPS and atomic
references is measured and printed out on the external printer. The user will thus have
the best possible knowledge of the rate error of the chronometer, and the precise
navigational time can be calculated from the number of days since it was last
synchronized and the average rate error per day.
Figure 1: Hamilton 21 Marine Chronometer
GPS and Silicon Clock Display Panel
The TTC has an electronic display panel which indicates the UTC time, date, latitude, and
longitude from the GPS clock as well as UTC time and date as maintained by the silicon
RTC clock.