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    Re: A simpler Bygrave ?
    From: Hanno Ix
    Date: 2010 Feb 7, 14:43 -0800

    So far I have not received any answers why a single scale Bygrave  never has been implemented. I suspect it has to do with the use of such a thing, however, it is not clear to me. However, I am no sailor.

    There must be some of you so knowledgeable in CelNav who have an opinion. Please, just drop me a note.



    PS, again: in the formulae below  x=1...89; should be replaced by x=(1:89)/180*PI

    From: Hanno Ix <hannoix@sbcglobal.net>
    To: NavList@fer3.com
    Sent: Fri, February 5, 2010 4:43:47 PM
    Subject: A simpler Bygrave ?

    Ageton's method can be, mathematically at least, performed with a single scale,  log cosec or log sec.

    Therefore, it should be possible to create a version of the Bygrave that contains just a single scale of cosec or sec.
    For convenience, one could add one or more cursors as convenient.

    Note:  The CelNav on Starpath's Emergency Navigation Card can be reduced to this method. 
    Just compare their N(x) Table with :   n(x) = logn(cosec(x))  for x=1...89;

    I can see certain mechanical advantages of a one-scale Bygrave. I am sure this has occurred to somebody else long ago, too.

    Therefore I ask why, despite its seeming simplicity, such a version has never been implemented.


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