| 摘要 |
PROBLEM TO BE SOLVED: To provide the subject device relatively inexpensive compared to other similar ones, intended to use only at times when it is needed such as at harvests so as to bring crop damage to a minimum without killing birds/ beasts. SOLUTION: This effective bird/beast-repulsive device is so designed as to emit guarding cries or groans inherent in birds/beasts and hard to be learned and also combine such cries with other repelling sound(s) and present the combination at random with raised sound quality.
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