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    Re: Raw data for bubble
    From: Bill B
    Date: 2007 Mar 09, 20:41 -0500

    > Bill wrote:
    >> The second paragraph is what I mean. Take the Hc (calculated elevation, not
    >> Ho--observed elevation) from your AP every 4 to 5 minutes and plot that
    >> slope. Fit that slope to the observations.  Then you are working against a
    >> known and can more easily detect outliers.
    Peter replied:
    > This is a new method for me. I calculate the 'Change of Altitude in 5
    > Minutes of Time' as a function of azimuth and latitude. The main thing
    > is to end up with the actual (apparent) rise or fall as a line, used
    > to compare the sights made against. They are plotted on graph paper,
    > altitude vertically, time horizontally. If the sights were perfect
    > their slope would be parallel to the calculated slope. The extent that
    > they do not fit that slope is an indication of error, but only of
    > random error.
    Yours is new method to me.  Somewhere in the recesses of my aging gray
    matter it sounds vaguely like a compass checking method using a repeater.
    Perhaps having to do with amplitudes?  Since I do not have a repeater and
    the gear needed, I have browsed chapters pertaining to the method, but
    failed to grasp the big picture.
    Come to think of it, I recall there is a relatively painless way to
    calculated change of Hc over time, but can't put my finger on it.
    Is this close to your method or am I--as usual--deeply confused and way off
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