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    Re: Bygraves
    From: Brad Morris
    Date: 2009 Jul 22, 10:31 -0400

    I also had a look at Datalizer.  They offer 2D models, not 3D.
    
    Gary's 2D model requires motion in X and Y to align scale 1 to scale 2.  This 
    combined motion cannot be executed in the models shown on the Datalizer site.
    
    A linear 2D model, such that it conforms to the type of models offered by 
    Datalizer, would be huge.  Ronald has determined the length of the scales and 
    they would be impractical for a linear 2D type of slide (4.143 meters and 
    7.584 meters for inner and outer scales, respectively).  This assumes, of 
    course, that you would wish to maintain the result within 1-2 arc minutes. 
    Further, these lengths presume that you only wish to solve for when the 
    values are between 0d 20' and 89d 40'
    
    Similar rules (Otis cylindrical and Fuller cylindrical) have very long scales 
    that are made practical by wrapping around a cylinder.  As a practical 
    matter, once the length of the scales is above 0.5 meters, these become a 
    nightmare to store and use.
    
    In a study provided to the NavList, I estimate that to obtain 1 arc minute 
    errors over 0 to 90 degrees, inclusive, you need a scale length on the order 
    of 70+ KILOMETERS, highly impractical.  In order to use this, in a 2D model, 
    you would align the scales and then get in your car to drive to the other end 
    to observe results.
    
    I believe Datalizer to be a non-starter.
    
    Best Regards
    Brad
    
    
    
    -----Original Message-----
    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of rob
    Sent: Wednesday, July 22, 2009 9:57 AM
    To: NavList
    Subject: [NavList 9178] Re: Bygraves
    
    
    according to a pdf on the site, typical one time setup fees are
    $1,500.00 and run costs 3-5 per unit (I think this assumes commercial
    runs in the 1,000s). Seems interesting.
    
    Rob
    
    >
    > PS: To your knowledge has anybody talked to " Datalizer Slide Charts" 
    (datalizer.com)? The site seems to be indicating they are open to small runs 
    of related products.
    >
    
    
    
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