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    Re: Station pointer London UK
    From: Alexandre Eremenko
    Date: 2012 Apr 4, 17:32 -0400

    Ken,
    Yes, it looks exactly as the Soviet model, as far as I can judge from
    those tiny pictures:-)
    I am still surprized: is there really any substantial demand for this
    heavy and expensive toy, I mean demand that is not covered by e-Bay?
    Why else would they make it?
    
    You can certainly solve the same problem will all precision needed
    for practical navigation with a simple plastic station pointer
    you always had, or with a simple computer program.
    
    Besides, there is no place to store this thing in a small boat:-)
    
    Alex.
    
    On Wed, 4 Apr 2012, Ken Gebhart wrote:
    
    >
    > Alex,
    >
    > Yes it is made by the same factory, and possibly is a copy of the
    > Russian model. Your comment is certainly correct, and we are
    > replacing "determine the direction" with "identifies".  As for the
    > two solutions, we didn't want to confuse the reader, or start a new
    > dialog about the math.  Thanks for your comments.
    >
    > Ken
    > On Apr 4, 2012, at 12:56 PM, Alexandre E Eremenko wrote:
    >
    >>
    >> Indeed!
    >>
    >> I am surprized. They do not say who makes them,
    >> Ken, is it by the Astra factory?
    >> The construction seems exactly the same as of the Soviet one
    >> that I have, except that the Soviet one is made entirely of bronze,
    >> and this one of an aluminium alloy.
    >> The box is of slightly different construction.
    >> (Soviet ones on e-bay usually cost a bit less).
    >>
    >> There are several imprecise points in the Celestaire description.
    >>
    >> a) You do not need to measure the DIRECTIONS (bearings) of 3 objects
    >> but only TWO HORIZONTAL ANGLES between them. This is done with
    >> a sextant. (A direction is measured with a compass, and it is
    >> hard, if not at all impossibe to measure with 1' accuracy).
    >>
    >> b) "There is only one solution". There are generally 2 solutions.
    >> The are usually far apart, if one takes the right objects to
    >> measure angles between them, and one of the solutions is usually on
    >> land.
    >> Geometrically, these solutions are the points of intersection
    >> of two circles (position lines). Two circles usually intersect at 2
    >> points.
    >>
    >> Alex.
    >>
    >>
    >>
    >
    >
    >
    >
    >
    > : http://fer3.com/arc/m2.aspx?i=118702
    >
    >
    >
    
    
    
    

       
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