Displays a Period Determination box, in which all parameters (a/o Base and Unit selections, Start, End, Steps values) are taken over from the current Period Window. Click the Apply button to start a new period analysis calculation and to create the corresponding Period Window.

A typical usage of the Refine period analysis command is to refine the accuracy and/or scan range of the period determination. Enter Start and End values that narrow the calculation interval and choose a higher Steps value.