Good morning Erik;
@ Erik...
I believe the reference to "absurdness of identicality" was with respect to the notion that different load values... which, when calibrated, produce identical results (-1, 0, 1); and those results are expected to yield perfectly corrected and accurate measurements.
There is some irony to this notion of absurdity as well. After all of the care, attention, and expense taken to ensure the ultimate degree of accuracy of the standards used, the benefits of that effort diminishes rapidly as the distance away from the center of the unit circle is increased. The common user is never made aware of either the absurdity nor the irony, because the biases applied to ¡°accurately¡± define the standards which are themselves embedded into the calibration, are ¡°accepted¡± and remembered by the AnyVNA to which those biases are applied with great confidence. That confidence is then rewarded by the verification of calibration success through a re-measurement of those same standards, and the user¡¯s realization that all of the uncertainties embedded in the system (including those introduced by the correction polynomial) have been accounted for and removed from the final measurement. Through this process, the common user becomes satisfied with the accuracy of the measurement, unaware of the in inaccuracy introduced by their attempt at improving it.
Furthermore; the accuracy corrections introduced, while small and often subtle, grow significantly as the measurement is removed from Z0, while at the same time diminishes toward zero in it¡¯s consequence to the magnitude of uncertainty in the measurement itself. If the corrections are not accounted for in the uncertainty model, the uncertainty boundaries become asymmetrical and themselves become an unavoidable uncertainty.
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73
Gary, N3GO
