AD Instruments AD1062P Manual De Usuario página 229

Sin = A/B or C/D, where = phase shift (in degrees) between the two signals.
From the formula above:
θ = ±arcsine (AIB) or ±arcsine (CID)
must be in the range of (0— /2) or (3 /2—2 ) if the main axis of the ellipse is between
I and III quadrant, . If the main axis is at II and IV quadrant, must be in the range of
( /2— ) or ( —3 /2).
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