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Telephone ringer load simulator

  • US 4,309,578 A
  • Filed: 06/09/1980
  • Issued: 01/05/1982
  • Est. Priority Date: 06/09/1980
  • Status: Expired due to Term
First Claim
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1. As a new article of manufacture, a telephone ringer load simulator for use in conducting tests of the condition of an individual subscriber circuit instituted from a telephone office comprising:

  • a pair of terminal members of generally elongated configuration and having a means on each of two opposite ends thereof for the engagement upon a corresponding pair of connections on an existing building entrance terminal;

    a single conductor interconnecting said means to provide a short of the circuit at said building entrance terminal;

    a resistor and an avalanche discharge device in series with said single conductor, said resistor having an effective resistance value equivalent to a fractional multiple of the resistance provided by an actual ringer, said discharge device being conductive at a voltage slightly below normal ringing voltage, and having a cutoff voltage at a value substantially above normal tip voltage;

    whereby said telephone ringer load simulator imposes substantially no load upon the subscriber circuit during normal operating conditions, and provides a sufficient ringing load to permit current measurement.

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