The method involves detecting a first signal characterized by a
periodically occurring first event, detecting a second signal
characterized by a periodically occurring second event, and based on both
the detected first and second signals, generating a third signal
characterized by a periodically occurring third event. The method also
involves automatically adjusting the phase of the third signal so that
the periodically occurring third event occurs at a predetermined location
between the first and second events of the first and second signals.