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    Re: Bygrave Scale Lengths
    From: Hewitt Schlereth
    Date: 2013 Jan 30, 11:53 -0800

    Brad, that's the way I would read it. Somewhere there is an F Table. Anyone 
    for Raiders of the Lost Table?  :-)
    
    Hewitt
    
    
    Sent from my iPad
    
    On Jan 30, 2013, at 11:43 AM, "Brad Morris"  wrote:
    
    > Hewitt
    > 
    > There is an additional "Table".
    > 
    > Perhaps that table does show "official instructions".  That would be
    > fantastic!  The updated instruction then says
    > 
    > "Use F-Table when declination is near zero and when the hour angle is near
    > zero or 90 deg"
    > 
    > Or did I slaughter that too!?  :-?
    > 
    > Image http://fer3.com/arc/img/122161.img_2161.jpg shows the first half of
    > the Table.
    > 
    > Image http://fer3.com/arc/img/122161.img_2162.jpg shows the second half.
    > 
    > Can you make out what the title of the F-Table is?
    > 
    > Oh yeah and... Thanks!
    > 
    > Regards
    > Brad
    > On Jan 30, 2013 2:06 PM, "Hewitt Schlereth"  wrote:
    > 
    >> ------------------------------
    >> 
    >> Brad, it's been a long time since I did translations from German and I have 
    never had hands on any cylindrical slide rule, in but the phrase,
    >> 
    >> "Bei d nahe 0 oder t nahe 0 und 90  verwende F-Tafel",
    >> 
    >> the verb "verwende" means 'use' or 'employ' an 'F-Table', which I would 
    take to mean something ancillary to the main slide rule, like say a printed 
    table.
    >> 
    >> Hewitt
    >> 
    >> 
    >> 
    >> Sent from my iPad
    >> 
    >> On Jan 30, 2013, at 6:21 AM, "Brad Morris" ** wrote:
    >> 
    >>> 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?
    >>>> 
    >>>> ++++++
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    >>>> 
    File:


    >>>> >>>> *Attached File: 122161.img_2160.jpg** >>>> * >>>> *Attached File: 122161.img_2161.jpg** >>>> * >>>> *Attached File: 122161.img_2162.jpg** >>>> * >>>> *Attached File: 122161.img_2164.jpg** >>>> * >>>> *Attached File: 122161.img_2166.jpg** >>>> * >>>> *Attached File: 122161.img_2167.jpg** >>>> * >>>> *Attached File: 122161.img_2168.jpg** >>>> * >>>> *Attached File: 122161.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 >>> >>> >> >> >> >> >> View and reply to this message: http://fer3.com/arc/m2.aspx?i=122168 >> > > > > > View and reply to this message: http://fer3.com/arc/m2.aspx?i=122169 > >

       
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