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    Atomic Watch (was: Extremely poor conditions??)
    From: Alexandre Eremenko
    Date: 2012 Mar 21, 21:31 -0400

    Greg wrote:
    > digital atomic clocks jump a complete minute
    > on me out of the blue for no reason.
    Following Greg's insight, I added one ``leap minute''
    to the time recorded by Bill's Atomic Watch and obtained these results:
    GMT 21:34, Astra, Sun. Errors: -1'5, -3'3, 0'1, 0'8, 3'8
    Average: 0'0, sigma=2'3
    GMT 21:46, Astra, Sun. Errors: 0'3, -0'3, -0'4, -0'3, -0'3
    Average: -0'2, sigma=0'25 (Bill's series, our best of the day!)
    GMT 21:54, Astra, Sun. Errors: -0'8, -1'8, 1'6
    Average: -0'3
    GMT 22:38, Astra, Sun. Errors: -0'6, 2'2, 0'9, 0'1, 1'2, 0'6
    Average: 0'7, sigma=0'9
    GMT 23:46, Astra, Venus. Errors: 0'9, -0'6, 1'2, -1'6, -0'7
    Average: 0'1, sigma=1'0
    GMT 23:58, Astra, Venus. Error: 4'6 (This is Bill, chilled.
    Bill is a Sun specialist buts I compete with him in
    stars observations :-)
    Pocket sextant:
    GMT 22:14, Sun. Errors: -0'8, -3'2, -0'2, -3, -2'7
    Average: -2'0, sigma=1'2
    GMT 00:03, Venus Errors: -0'2, 1'0, 3'0
    Average: 1'3
    (Pocket sextant scale cannot be read to less than 1')
    What can I add? Well, maybe I have to explain how my analog watch was used
    (in the 4-th and 5-th series, when Bill went for a walk on the jetty).
    I measured altitude, then looked quickly at the watch, SECONDS only,
    subtracted one, and quickly recorded... Then I looked at the hour and MINUTE
    on the Atomic Watch which stood on a piece of concrete nearby next to
    my notebook, and recorded hours and minutes. Then I carefully read the
    scale and recorded the altitude.
    The reason I used such a procedure is that it really takes me
    some time to read the minute of my analog watch; the second and minute
    hands are not synchronized,
    as is the case even for very expensive watches,
    so I decided
    to take this shortcut using the Absolutely Precise Atomic Pocket
    Watch which bill left with me while going for a walk.
    What else?
    I sincerely thank all who participated in this vivid discussion.
    I really learned a lot of interesting things about dip and refraction.
    I mean it.
    But I still believe that the dip correction is always negative.
    Because I am sort of claustrophobic, and if it were positive on that day
    I'd definitely feel it, feel like being in a pit...
    Thanks again to everyone. And especially to Greg. Now I can at least sleep
    well, without this nightmares of being in a pit with positive dip correction:-)

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