作者: Robert J. Kreutzfeld
DOI:
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摘要: The present invention provides a method and apparatus for counting the number of occurrences that mobile unit comes within range stationary unit. is useful in laps which runner or swimmer completes through course. In one aspect, includes timer which, cooperation with information generated by lap counter, produces corresponding to time, average minutes per mile other such data. preferred embodiment, transmitter emits an infrared signal create zone detection triggers receiving attached each time passes detection.