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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Timekeeping and sight time records
From: Pierre Brial
Date: 2005 Mar 18, 07:23 +0400
From: Pierre Brial
Date: 2005 Mar 18, 07:23 +0400
Jared, The Citizen is only availaible in Japan, but could be ordered by mail (I've got one). 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 battery life for the Citizen is 5 year so it is not to much a hassle. It is technically feasible to make these watch kinetic or solar powered, but unfortunately there isn't a great interest amongst customer for extreme accuracy, so manufacturer don't bother. I've got also a Muhle Quartz marine chronometer (actually manufactured by Hanseatic instruments) which keep 15s/year. It seems to be the last marine chronometer currently available. The battery last one year but it is very easy to change. Regards Pierre Jared Sherman a ?crit: > > Pierre- > Very interesting. When I had asked Citizen about their Eco-Drive models (no > battery, no winding, no need to open the watch, les need to service it, > etc.) IIRC they only mentioned a more conventional 30 seconds per month. > Perhaps they've been hiding that 5 second model from the US market--they > should be bragging about it! > > Back when my Accutron was still state of the art (pre-quartz) Bulova had > developed one model for aircraft that consisted of three stacked "Type 214" > movements, which mechanically averaged each other and drive one set of hands > on the one dial. Once in a while they still come up on eBay, etc., as they > were used on commercial airliners. For a while, they were the most accurate > "civilian" time product on the planet, short of spending millions on an > atomic clock. Then came quartz! > > What I find very disappointing is the amount of routine maintenance that > most watch companies claim their products need. Even Rolex will claim the > watches should receive routine cleaning every 3(?) years, which makes it > expensive to keep up the watches and certain that the rate of the watch will > be changed. And even with their screw-down stem, Rolexes and other "good" > water-resistant watches will leak unless the seals are regularly replaced. > More nuisance value! > > Some years ago when LEDs were new, someone introduced a fully potted sealed > LED watch with solar cells and magnetic contacts instead of a "sealed" stem > or buttons. I can't find reference to it, but know it existed--and the rate > could also be adjusted by the user! > > Of course any mechanical watch will suffer daily variation from gravity > effects, etc. so for regularity an electronic watch with stepping motor or > digital display in theory is most accurate, but then there's the battery > problem.Seiko and Citizen's solutions for permanent (kinetic or solar) > watches would seem to be the most accurate/reliable way to solve that > problem as well, but they still come back to promising Timex accuracy...with > routine seal replacement, etc. required on top of the pricing. > > I guess we've still got a way to go in what truly DURABLE accurate watches > can be developed. I'm content to leave my aging Accutron regulated at about > 30 seconds per month. Well, 30-60 as the battery ages out every 18-24 > months, I could do better if I changed it annually without fail. That's > good enough for most of what I do, and a backup for the GPS. And Timex.