There is an Auto Calibration routine in the controller that will move the stage and figure out the values necessary for Quadrant Order and Cal Value. However if the routine fails, use this manual on how to determine these settings manually with trial and error.
Quadrant Order is used by the controller to interpret the error seen by the Quad Photo Multiplier Tube(QPMT or PMT) and the direction it needs to move to correct it. Say if the PMT registers the sample has moved from the center to upper right quadrant of the PMT , what direction should the controller move (positive x , positive y , negative x, negative y direction) to bring the sample back to center.
When the system has the correct Quadrant Order , in Ready state, when stage is moved in Positive X direction , you will see PMT have a negative Xerror. (Displayed on the bottom line of the LCD), Then when you move in positive Y direction , PMT will see a negative Yerror. If not the Quadrant Order needs to be corrected.
If moving the sample in one direction causes both Xerror and Yerror to change , then PMT is not Rectilinear with respect to the stage , turn the PMT by 45 degrees or adjust it until you only see either Xerror or Yerror change.
There are 8 possible Quadrant Order 78, 57, 147, 228, 27, 198, 177 and 108. 78 is the default. A new Quadrant Order is set with the "LK F" command , a system restart is needed for the new setting to take effect, so save setting using "SS Z" command and reset the controller.
Final check is when you lock onto a sample , if the stage doesn't run away or move in spirals your quadrant order is correct.
Unless the PMT is rotated , moved to a different photo port, additional optics mirrors are introduced, Quadrant Order will remain the same.
Cal Value or gain is the servo gain factor. Too high a value will result in nervous jerky tracking operation, too low a value will result in sluggish tracking and lost targets.
Default value is “10” , here is how to test and see if it's good enough.