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    Re: Bygrave Scale Lengths
    From: Wolfgang Hasper
    Date: 2013 Jan 30, 20:41 +0100

    Brad,
    
    > Bei d nahe 0 oder t nahe 0 und 90  verwende F-Tafel
    
    translates to 
    
    "With dec close to 0� or LHA close to 0� and 90� use 
    F-Tables" 
    
    (nomenclature adapted)
    
    F-Tables being the alternative German sight reduction 
    method in these days.
    
    Best
    Wolfgang
    
    
    
    Am Mittwoch, 30. Januar 2013 15:21 schrieb Brad Morris:
    > Hi Gary
    >
    > Image 122161.img_2160.jpg tells the tale!
    >
    > In it, we see the rules for using the device. 
    > Within those rules, we see the standard
    > admonishments for the MHR1, with one major and
    > glaring change.  In German, we have:
    >
    > Bei d nahe 0 oder t nahe 0 und 90  verwende F-Tafel
    >
    > Which I loosely translate to:
    >
    > Do not use the slide rule (F-Tafel) when declination
    > is near zero deg or when the hour angle is near 0 or
    > 90 deg.
    >
    > The is no longer any numerical prohibition like 0
    > deg 20 min or 89 deg 40 min.  It just says "near"
    > (nahe).  This could be understood to say the same
    > thing, since 20 min is near to zero.
    >
    > But given the precise directions of the MHR1, I
    > would like to think that near now means that the
    > scale has been extended downwards and upwards, as we
    > have discussed, towards 0 and 90 deg.  To what
    > value?  The images do not reveal this data point. 
    > Pity.  I'd like to think that it went to within an
    > arc minute, the trick of a tiny offset to include 0
    > deg 90 deg not withstanding.
    >
    > What do you make of the conversion table, the
    > adjustment knobs and the magnifying glass? 
    > Magnifiers are typically associated with verniers
    > and fine graduations.
    >
    > Regards
    > Brad
    >
    > On Jan 30, 2013 12:39 AM, "Gary LaPook" 
     wrote:
    > > ------------------------------
    > >
    > > I am attaching some photos I took of the MHR2 in
    > > London in 2009.
    > >
    > > gl
    > >
    > > +++++++++
    > >
    > > I would be very curious to see what the scale
    > > lengths and operating ranges of the MHR2 table top
    > > calculator. Ronald - Do you know these values?
    > >
    > > ++++++
    > > --------------------------------------------------
    > >-------------- NavList message boards and member
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    > > --------------------------------------------------
    > >--------------
    > >
    > > Linked File:
    > > http://www.fer3.com/arc/imgx/f1-IMG_2170.JPG
    > >
    > > *Attached File:
    > > 122161.img_2160.jpg >.img_2160.jpg> *
    > > *Attached File:
    > > 122161.img_2161.jpg >.img_2161.jpg> *
    > > *Attached File:
    > > 122161.img_2162.jpg >.img_2162.jpg> *
    > > *Attached File:
    > > 122161.img_2164.jpg >.img_2164.jpg> *
    > > *Attached File:
    > > 122161.img_2166.jpg >.img_2166.jpg> *
    > > *Attached File:
    > > 122161.img_2167.jpg >.img_2167.jpg> *
    > > *Attached File:
    > > 122161.img_2168.jpg >.img_2168.jpg> *
    > > *Attached File:
    > > 122161.img_2169.jpg >.img_2169.jpg> *
    > >
    > > View and reply to this message:
    > > http://fer3.com/arc/m2.aspx?i=122161
    >
    > View and reply to this message:
    > http://fer3.com/arc/m2.aspx?i=122166
    
    
    
    

       
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