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

• Current Assignee: Porta Systems Corp. (Transdigm Group Incorporated)
• Original Assignee: Porta Systems Corp. (Transdigm Group Incorporated)
• Inventors: Ahuja, Om P.
• Primary Examiner(s): Robinson, Thomas A.
• Application Number:
  US06/157,507
• Time in Patent Office: 575 Days
• Field of Search: 179/175.2 B, 179/2 A, 179/84 R, 179/84 C, 179/84 L, 179/175, 179/1 PC, 179/184, 179/186, 179/175.2 R, 179/175.3 R, 179/175.2 C, 179/190
• US Class Current: 379/30
• CPC Class Codes: H04M 19/04 the ringing-current being generated at the substations
• CPC Class Codes: H04M 3/323 for the arrangements providing the connection (test connection, test call, call simulation)

Abstract

A module incorporating a single conductive line having in series a high resistance and a gas tube arcing device. The module includes means for interconnecting the same across the tip and ring circuits at a building entrance terminal to place on the line the equivalent of approximately ten percent of a normal alternating current ringer load. In the absence of a connected telephone set on the premises, the phantom ringer operates at 100 volts peak, and cuts off at 60 volts peak. Thus it poses no load during normal on hook and off hook operating conditions.

Claims

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.

2. The article as set forth in claim 1, further characterized in said avalanche discharge device comprising a gaseous discharge tube.

3. The article as set forth in claim 2, further characterized in said resistor and gas discharge tube being mounted within a transparent cover element through which operation of said gas tube may be observed.