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Siren detector

  • US 3,992,656 A
  • Filed: 09/11/1975
  • Issued: 11/16/1976
  • Est. Priority Date: 09/11/1975
  • Status: Expired due to Term
First Claim
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1. An audio range siren detector comprisingaudio pick-up means for transducing variable frequency audio signal energy into variable frequency electrical signal energy,narrow band signal producing means responsive to said audio pick-up means to produce separate outputs when predetermined closely spaced fundamental siren frequencies appear in said electrical signal energy,gated control means responsive to the signal producing means only upon pre-determined reduction of outputs therefrom within a limited time following initiation of any such output, andutilization means responsive to said gated control means.

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