NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Gary LaPook
Date: 2015 Sep 24, 01:18 -0700
A further update of my experiment. I started checking three cheap watches on october 7, 2009, al;most six years ago. I have not yet had to replace any of the watch batteries. Comparing the actual errors in each of the watches compared with the predicted errors shows that watch A is 75 seconds faster then precicted, watch B is 22 secoonds slow and watch C is 31 seconds slow. If using just the one watch with the worst error, 75 seconds, then a longitude computed by that would be in error by 19 minutes on longitude. If you use the average of all three, 22 seconds fast, you end up with a longitude error of 5.5 minutes of longitude. All this after six years using three $17 watches without any update from a radio time signal.
See prior reports:
http://fer3.com/arc/m2.aspx/Watches-chronometers-LaPook-mar-2011-g16014
http://fer3.com/arc/m2.aspx/Watches-chronometers-LaPook-may-2013-g24211
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