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    Re: Centring Error Detector
    From: Brad Morris
    Date: 2014 Jan 21, 22:47 -0500

    Hi Don

    I don't know how you are getting the UK Patent reprints.  Perhaps you can show us how.  Until then....

    This patent: Apparatus for testing the centering of divided arcs of circles
    United Kingdom Patent 316438-A  is a valuable device that uses prisms to let a navigator (not a calibration house) test his arc.  Its what Frank and Alex were briefly chatting about 7 years ago.

    The links from back then do not work now.  Would you mind terribly?


    I half expected the link to the 7 year old email to show.  It did not.  I used the fer3.com site to reply. 


    On Jan 20, 2014 7:37 PM, "Brad Morris" <Bradley.R.Morris---.com> wrote:

    Hi Frank

    Here's a 7 year old post that caught my eye.

    It describes a method that permits you to measure the arc error. It all makes sense to me but I'm trying to figure out how the prism is aligned to the optical path assigned to the horizon.

    Would you happen to have a copy of the patent?


    you mentioned that this equipment was offered by Heath and you had the catalog / book for it. Do you have it still?

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