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Title: Electric indicator system for ball games

Abstract: An improved electric circuit and indicator system for a court game, such as tennis, using conductive elements on both the ball and outside the court playing area to activate an indicator when the ball drops outside the playing area; wherein said system includes means for deactivating said indicator when the ball contacts one of the playing lines to avoid erroneous indication caused by a skidding ball.


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Other info:


Inventors: Von Kohorn, Henry (Greenwich, CT, US)

Application Number: 729996
Filing Date: 1976-10-06
Publication_date: 1978-05-30
Assignee: Schlager; John J. (Springfield, NJ)
Primary Class(es): 473/467 340/323R
Other Classes:
US Patent Ref:
3883860May, 1975Von Kohorn340/323.
3982759Sep, 1976Grant340/323.

Other Refs:
Primary Examiner: Yusko, Donald J.
Assistant Examiner:
Attorney: