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    Re: Extremely poor conditions??
    From: Alexandre Eremenko
    Date: 2012 Mar 21, 17:36 -0400

    Greg,
    
    > I have had two different digital atomic clocks jump a complete
    > minute on me out of the blue for no reason.
    
    Are you serious??? Then who needs such clocks?
    We compared once with the GPS clock but I don't remember at what time
    exactly. If I were comparing myself I'd look at the seconds only,
    not on the minutes:-) But Bill was comparing. (All electronic toys,
    except a Casio calculator are his).
    
    I agree that I could misread a minute from my analog watch.
    
    > I still think you are a minute out in your time rather
    > than having a horizon 3.5 miles away elevated 11 moa.
    
    I also think that any efect of refraction cannot be that large.
    Moreover I think that the dip correction can never be positive,
    whatever is the state of the atmosphere.
    
    I looked at a remote shore in the S direction, and found absolutely
    no irregularities.
    
    And that the effect of any refraction on a Sun at 22 degrees high can not
    be much more than
    the Almanac says, I also do not believe.
    
    I estimated again the possible effect of the side error using Chauvenet
    formula.
    The side error, even a large one cannot be responsible for the effect
    either.
    
    What else???
    Well, let me reduce our observations again, assuming 1 min time error,
    as you suggest:-)
    
    > You will need to go back out to the lake to take
    > more observations using the GPS time directly from the GPS unit or a
    > shortwave time tick directly.
    
    Well, it is not easy for me to go back there:-(
    I am in Lafayette, IN, this is 3 hours drive in one direction,
    and I don't have much time.
    
    I am waiting for Frank to come back (I suppose he is in Greenwich on some
    conference now) and confirm his words that 10' undershots of Sun at 22
    degrees are "notorious"
    for the lake Michigan:-)
    
    Alex.
    
    
    
    
    

       
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