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    Bygrave Slide Rule Emulator
    From: Bill Ritchie
    Date: 2021 May 14, 10:16 -0700

    I recently used the Bygrave Slide Rule Emulator (link posted 2020 Apr 02) to work through Sir Francis Chichester’s sights on his Tasman Sea crossing 90 years ago. That gave me several ideas for improvements to what was a ‘proof-of-concept’ version.

    I have now posted a new version in the same location. The image is a screenshot alongside a photograph of the genuine article. Apparent rotational freedom has been increased to +/- 540 degrees, the scales are now helically inclined, a functional scratch pad has been added and mouse controls have been improved. The User Notes are accessed from within and include example and blank worksheets.

    I hope you like it. I anticipate some brickbats from the stalwarts for adding a ‘Pointer Assist’ feature. These are (hopefully helpful) digital readouts of the scale positions against the pointers – obviously not genuine, but you can turn them off as they have been for the screenshot. You can run the emulator from this link. Traditional Bygrave Emulator 

    My other emulators, Modern Bygrave Emulator and Linear Slide Rule Emulator remain unchanged.

    Bill Ritchie. 50N 003W


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