How do they keep big Ben in sync these days? Eg, who decides it is running
fast or slow? In the past I've been told they steered to Greenwich
observatory who would shoot a cannon off and drop a red ball to announce
the time to London... on my recent trip to Greenwich observatory I
discovered they
Sorry Tom, that BBC news item is ten years old, and it looks like the video
has been removed. There are a number of videos on Youtube which talk about
adding or removing old pennies from the pendulum to correct it. See, for
example:
https://www.youtube.com/watch?v=_Elffjsjbio
An eight-minute
Tom Van Baak wrote in :
|Steve, et al.
|
|Some good history resources:
...
|"Special Issue; The System of Units"
|https://www.ptb.de/cms/fileadmin/internet/publikationen/ptb_mitteilungen\
|/mitt2012/Heft1/PTB-Mitteilungen_2012_Heft_1_en.pdf
There is a v2 of that available, also in english:
Steve, et al.
Some good history resources:
"Special Topic 50 years of time dissemination with DCF77"
https://www.ptb.de/cms/fileadmin/internet/fachabteilungen/abteilung_4/4.4_zeit_und_frequenz/pdf/2011_PTBMitt_50a_DCF77_engl.pdf
"Time - the SI Base Unit Second"
