FR550781A - - Google Patents

Info

Publication number
FR550781A
FR550781A FR550781DA FR550781A FR 550781 A FR550781 A FR 550781A FR 550781D A FR550781D A FR 550781DA FR 550781 A FR550781 A FR 550781A
Authority
FR
France
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
Other languages
French (fr)
Publication date
Application granted granted Critical
Publication of FR550781A publication Critical patent/FR550781A/fr
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G04HOROLOGY
    • G04CELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C21/00Producing acoustic time signals by electrical means
    • G04C21/16Producing acoustic time signals by electrical means producing the signals at adjustable fixed times
    • G04C21/30Producing 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
    • G04C21/32Producing 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
    • G04C21/326Producing 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 adjustable from the different places themselves
    • GPHYSICS
    • G04HOROLOGY
    • G04CELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C21/00Producing acoustic time signals by electrical means
    • G04C21/16Producing acoustic time signals by electrical means producing the signals at adjustable fixed times
    • G04C21/30Producing 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
    • G04C21/32Producing 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

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
FR550781D Expired FR550781A (ref)

Publications (1)

Publication Number Publication Date
FR550781A true FR550781A (ref) 1923-03-20

Family

ID=1538336

Family Applications (1)

Application Number Title Priority Date Filing Date
FR550781D Expired FR550781A (ref)

Country Status (1)

Country Link
FR (1) FR550781A (ref)

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