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Plot and as with

Best fit to data (blue line). Reference gradient (red lines):-605ms/day/deg C.
this is for an uncompensated steel pendulum -605ms/day/C (we hope to acheive within 10ms/day/C with compensation)

Comments (see all | edit)

26 Feb 2011 [20:00]
nothing to report - just enjoying 2 weeks during which the clock has lost only 0.5 seconds. Not sure why the recent slowing down - temperature compensation is ok [link] , still not certain about the barocompensator [link] but there is a lot of noise on the plot. The biggest effect at the moment is draughts, I think, caused by differential temperature with the centrally-heated room below. As spring settles in we should see less of this.
08 Feb 2011 [21:23]
ADJUST: -250 ms/day to 30500. Reinstated the amplitude measurement plank at the top of the pendulum chamber. This might moderate the extremes of air flow that could be responsible for the observed fluctuations of going.

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Interval between data points: seconds [either 3 seconds (weather data is duplicated) or multiples of 60 seconds (all data is averaged)].

Contact:, Trinity College, Cambridge