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Re: Watches as chronometers
From: Brad Morris
Date: 2013 Jun 15, 16:25 -0400
From: Brad Morris
Date: 2013 Jun 15, 16:25 -0400
Bill
Gary stated "practical navigation", not OCD navigation (please take this kindly!).
Maybe its just me but I can't see the value of that sub-second correction when the fix itself has greater probable error than the correction itself. It seems as if its wasted effort, as the correction is still within the noise.
On Jun 15, 2013 3:52 PM, "Bill B" <billyrem42@earthlink.net> wrote:
On 6/15/2013 3:06 PM, Brad Morris wrote: > Roger that Gary! The almanac is published at 1 second intervals, your > chronometer need not be better than that. Yes and no. The NA Explanation Section, PRINCIPLE AND ARRANGEMENT 2. Principle. states that using UTC can result in and error up to 0!2 in longitude, and provides a corrections table based on the difference between UTC and UT1. The NA giveth and the NA taketh away under ACCURACY 24. Main Data :-) With a competent assistant and a rated timepiece, I will factor in DUT1 for values over 0.2 s for land based observations from a known location. For a pleasure craft underway that seems a bit OCD to me. I have not gone to the extremes Bauer has. > Are your watches in a temperature controlled environment? I had posted the threads names from the inception of the project. Much discussion on temperature. The answer to your question is in the posts. I say this not to be rebuke you. Rather, the discussions on temperature are wonderful, and showcase the intellect and imagination of some of the members, as well as an interesting reference to sledge chronometers. There is a detailed design for a timepiece oven (easier to keep the timepieces above the highest expected temperature than heat and cool them). My favorite suggestion for keeping a constant temperature was stringing three digital watches together on one band, and fastening the band around the user's belly to create a chronometer "oven." It is a good read. Bill B