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    Re: Finding IC for A-12 bubble sextants
    From: David Pike
    Date: 2021 Oct 6, 09:45 -0700

    You don't need to use the averaging mechanism for shots on the ground; it's only there to minimise acceleration errors when used in flight.  Using the averaging mechanism on the ground, you'd die of boredom before you'd finished.  If you have a seperate window for the average value compared to the index mirror reading as in the Smiths, Kelvin, Hughes sextants, then a separate check should be to set a fixed known value on the index scale, run the averager, and compare the two results. The difference should be no more than a minute or two of arc, and the run-time should be within a couple of seconds of that selected.  We're talking about 1940s alarm-clock mechanisms here. Don't expect too much.  DaveP

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