Now, simply drive the field boundary.  We recommend the Trimble sub-meter DGPS to collect the field boundary.  Your data will not be more accurate than the GPS you use.

Then tell the computer what size end-gun you plan to use (if using an End Gun).  The computer will take it from there, calculating the center of the field, length of the pivot, and area with and without the End Gun.  You may want to try several different End Guns (with or without pumps) to determine what difference each has on the result.

The software also has the capability to draw standard circles of a specified radius, move objects, or reshape individual nodes (for example if you want to change the End Gun coverage).

We recommend that you return to each point where the center pivot and the field boundary touch and verify the current GPS location still has clearance with the center pivot.
 

Limitations
This software only calculates full circle Center Pivots, not "Pie Cut" or partial circle pivots. It looks for the maximum coverage.  If different parts of the field have different yields, you may want to nudge the center pivot towards higher yield instead of more coverage.  This can be done with the editing tools.

Some "Pie Cut" center pivots can be computed by driving the field as if it were a full circle and then using editing tools to split the result to be a partial circle center pivot.