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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Accurate quartz watches
From: Dan Allen
Date: 2005 Mar 18, 15:42 -0700
From: Dan Allen
Date: 2005 Mar 18, 15:42 -0700
On Mar 17, 2005, at 8:23 PM, Pierre Brial wrote: > Other high-end quartz which claim an accuracy of less than 20 sec a > year are Seiko "Grand Seiko", Longines VHP, Breitling Colt and Rolex > Oysterquartz. All of them are battery powered. The Seiko SLL033 I have is a perpetual chronometer (automatic day and leap year) that I measured to be very accurate, about 1.5 ppm on average over 6 years, which is about 47 seconds a year. An Omega 1552.30 I have is even better at about 0.5 ppm or 15 seconds a year, also on average over 6 years. I do not know if they still make it. It is about 8 times more expensive than the Seiko. Both of these watches run their quartz crystals at 4-6X the usual 32768 Hz rate. I bought the watches in 1999. Thermally compensated twin-quartz watches used to be made by Seiko and Omega in the 1980s and they may have even been more accurate. Recent designs have neither used multiple quartz oscillators nor have they been thermally compensated, which are both big wins for the best accuracy. Dan
