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    Traditional Bygrave, Modern Bygrave and Linear slide rule emulators.
    From: Bill Ritchie
    Date: 2020 Apr 2, 03:40 -0700

    I have posted three slide rule emulators on child folders of https://www.vigilanceofbrixham.co.uk/Astron/SlideRules/ .

    1. TRADITIONAL BYGRAVE EMULATOR. This is the ‘proof of concept’ version. As I have never even seen a Bygrave slide rule, many assumptions have been made and some will be incorrect. Feedback via navlist.com or direct to my Gmail address of 1billritchie will be most welcome. It works ok and limited tests so far have given correct results. See Traditional Bygrave Emulator  and User Notes . Thank you, Francis, for your offer to meet and see your collection of cylindrical slide rules - alas this will have to wait until travel becomes sensible again.

     2. MODERN BYGRAVE EMULATOR. This is unchanged from my post of 2020 Mar 5, 12:45 -0800. It is now relocated at Modern Bygrave Emulator with integral user notes.

     3. LINEAR SLIDE RULE EMULATOR. This has been improved from the version in my post of 2019 Nov 22, 07:35 -0800. Emulations of the slide rules by Bob Goethe and Sean Johnston discussed in that thread are preloaded. The scales are now calculated, not images. There are 27 scales available, including haversines. Any scale, including duplicates, can be placed in any location and such bespoke rules can be saved for future use. It is located at Linear Slide Rule Emulator also with integral user notes.

    Keep safe,


    Bill Ritchie. 50N 003W



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