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Credit card monitor

  • US 3,959,789 A
  • Filed: 02/21/1975
  • Issued: 05/25/1976
  • Est. Priority Date: 02/21/1975
  • Status: Expired due to Term
First Claim
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1. A document holder, comprising:

  • a plurality of separators adapted to hold documents there between, said separators constructed from electrically nonconductive material and incorporating electrically conductive members on facing surfaces positioned to form normally closed electrical contact pairs, said contact pairs adapted to be held open by documents inserted there between;

    a switching means comprised of said contact pairs connected in electrical parallel;

    a power source electrically connected to said switching means;

    a time delay means responsive to said switching means; and

    an alarm means responsive to said time delay means.

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