Cardiac monitoring andor stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. The method includes detecting thrust and steering commands from an operating device which is connected to a control unit, and controlling the drive arrangement based on detected commands from the operating device for obtaining a desired course of travel of the watercraft, wherein a force is generated which acts towards a defined position on the watercraft. The navigation function returns program information for a local or remote computer. The player interface unit displays the number of bonus points received by the associated player. Additionally, the signal may be recovered when it comprises two channels of the same wavelength that are polarization multiplexed together.