A method and apparatus for measuring and controlling the phase difference or time difference between two signals is presented. Additionally, the drum rail that operates in connection with the rotating drum to lift a ball off of a ground is allowed to move in the horizontal direction. The implementation of the hierarchical list is accomplished by creating the hierarchical list in memory to mirror the actual structure resource, where the mirrored hierarchical list is sent to the end-user device, where the end-user device executes the browser to display the hierarchical list to allow the user to access the actual structured resources via the displayed hierarchical list.