[Phys-L] Allan deviation

[Bernard Cleyet <bernard@cleyet.org>]

Very interesting — as an amateur horologist, I’ve in the last week advanced to measuring the stability of clocks. (1)

Fascinating, as clocks are subject to more than just “white” noise.   In my opinion the dean of horologists is Philip Woodward who discusses Allan deviation, (2) which I’ve used to analyse the Trinity tower clock (Cambridge) and the Santa Barbara Court House tower clock. (3)  

So any of you familiar w/ this method?


1,  Being computer challenged, I necessarily manually use Kaleidagraph’s "spread sheet”. 
2,  In Rawlings (3rd ed.) and Woodward on Time.  

https://en.wikipedia.org/wiki/Philip_Woodward 
  
3,  Data on line. 

Santa Barbara Courthouse Clock

http://www.bisnoschallgallery.com/microset/data/


The Trinity Clock 


http://trin-hosts.trin.cam.ac.uk/clock/?menu_option=data&from=03/04/2009&channel=drift&channel2=0&to=15/04/2009&scale=auto&type=two

bc thinks this is "up JD’s alley”.