See if this works for you -
Create 3 user defined parameters using the FORMULAS

ARAMETERS panel, say "hole dia" , "pcd" and "angle"(making sure the types are length, length and angle respectively). These then appear in the specification tree under Parameters.
Create your sketch with a construction circle and a point coincident on the cicumfrence. Right click the dim for the circle, go to edit formula and make the dim equal to "pcd".
Exit sketcher, and create a hole on your point on the sketch. In the Diameter field of the HOLE DEFINITION panel, right click, select edit formula and make the Diameter equal to "hole dia". Fianlly, create a circular pattern. In the Angular Spacing field of the Circular Pattern Definition panel, right click, edit formula and make the spacing equal to "angle". You can now control your 3 varaibles be double clicking them in the parameters branch in the specification tree.
Hope I explained this ok.
Good Luck