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Application filed by Wilhelm BiemannfiledCriticalWilhelm Biemann
Publication of CH69084ApublicationCriticalpatent/CH69084A/de
G04C21/00—Producing acoustic time signals by electrical means
G04C21/16—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times
G04C21/30—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times with provision for a number of operations at different times, e.g. ringing the bells in a school
G04C21/32—Producing acoustic time signals by electrical means producing the signals at adjustable fixed times with provision for a number of operations at different times, e.g. ringing the bells in a school giving indications at a number of places each at a different time, e.g. system of alarms in a hotel
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Physics & Mathematics
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General Physics & Mathematics
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CH69084A1914-04-081914-04-08Selbsttätiger Kontaktapparat für an verschiedenen Stellen und zu beliebigen Zeiten zu gebende elektrische Signale
CH69084A
(de)