The pendulum clock in Trinity College, Cambridge was installed in 1910. It is remarkably accurate, known to be better than one second per month. In 2009 a system was installed to monitor the "going". The work was done as part of a 4th year MEng project at the Engineering Department. A sensor on the pendulum detects the going of the clock, which is compared to the accurate time signal from a GPS receiver.
Here is a graph for the last 30 days of drift (updated every 3 hours):
For an entirely mechanical clock the accuracy is remarkable.
A barometric compensator was installed at clock change - midnight 28 March 2010.
The clock is regulated as infrequently as possible so as to stay within +/- 5 seconds of the correct time. This enables the steady-state physics of the clock to be examined without unnecessary interference.
The black dots ● indicate that there is a comment relating to the time indicated. Blue arrows pointing down ▼ indicate that an adjustment was made to the Going of the clock by removing weights from the pendulum. Red arrows up ▲ indicate addition of weights to speed the clock up.
- 10 Mar 2014 [12:17]
- Thanks to Frank Barker for help with winding today.
- 03 Mar 2014 [23:29]
- Fun winding with suitable refreshments - Hamish Drewry, John Byrne, Ben Moss @B_R_Moss, Jessi Lloyd @Engineer_cat, Dan Safka, Filip Murar
- 24 Feb 2014 [23:08]
- Winding tonight by a gaggle of mostly Mathmos, Mary Fortune, Sam Tickle, Sean Moss, Alex Chamolly, David Mestel, Oliver Feng, Andrew Carlotti, Ben Barrett
- 17 Feb 2014 [22:43]
- Winding by Amy Hewer @Ms_AmyH and Alice Jones @AEMJ from BBC One Show who spring up everywhere, slinking about the College
- 15 Feb 2014 [15:30]
- Great winding from Carl Rütti