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Radio alarm system

  • US 4,319,230 A
  • Filed: 01/15/1980
  • Issued: 03/09/1982
  • Est. Priority Date: 01/15/1980
  • Status: Expired due to Term
First Claim
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1. A radio alarm system with back up capability having electric circuits for monitoring, controlling, operating and utilizing an electric circuit having electrical conductors including normally closed switches, said radio alarm system comprisingrelay means having electrical conductors;

  • a source of electrical energy;

    a radio transmitter for transmitting radio signals; and

    electrically conductive leads electrically connecting the relay means, the source of electrical energy and the radio transmitter in a back up circuit in a manner whereby the relay means is energized by electrical conductors of the electric circuit having normally closed switches and maintains said relay means normally open as long as said radio alarm system is in operative condition and when an electrical conductor of said radio alarm system is open-circuited, said relay means is deenergized and closes the back up circuit to actuate the transmitter to transmit radio signals indicating that an electrical conductor of a closed circuit of said radio alarm system has been open-circuited, said closed circuit of said radio alarm system and said back up circuit constituting different circuits.

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