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Automatic telephone alarm system

  • US 3,989,900 A
  • Filed: 11/04/1974
  • Issued: 11/02/1976
  • Est. Priority Date: 09/06/1973
  • Status: Expired due to Term
First Claim
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1. A plurality of automatic alarm systems for use in conjunction with existing residential telephones, each telephone being located in one dwelling unit of a multiple dwelling, each automatic alarm system comprising a power source, a timer, a selectively operable switch between said power source and timer for placing the timer in a running or non-running condition, alarm means for transmitting a remote signal that help is needed at the dwelling unit, means responsive to the running of said timer for a predetermined time for activating said alarm means, reset means activatable to reset said running timer to zero and to deactivate said alarm means, and means responsive to activation of said telephone by a resident for activating at least said running timer reset means, the timer, reset means, means responsive to telephone activation and at least portions of said alarm means for all of said systems, being located at a central area of said multiple dwelling.

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