Full duplex audio response device
Patent 4191855 Issued on March 4, 1980. Estimated Expiration Date: 
August 26, 1997. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
August 26, 1997. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3103558 3226480 3347988 3647972 Remote data line monitor Patent #: 3992587 InventorApplicationNo. 05/828101 filed on 08/26/1977US Classes:379/102.01, Remote control379/391, Sidetone control or hybrid circuit (e.g., induction coil)379/906TOUCHTONE MESSAGE TRANSMISSIONExaminersPrimary: Konick, BernardAssistant: Popek, Joseph A. Attorney, Agent or FirmInternational ClassesH04M 11/06 (20060101)H04M 3/487 (20060101) H04M 3/493 (20060101) Foreign Application Priority Data1976-08-26 JPAbstractIn an audio response device comprising an incoming trunk, a push button signal receiver, a voice output unit and a control unit and associated with a terminal set such as a push button calling telephone set, there is provided a full duplex audio response device which includes a hybrid circuit disposed in the incoming trunk associated with the terminal set and a band-pass filter interposed between the voice output unit and the hybrid circuit for filtering a frequency component corresponding to a specified push button, and in which the hybrid circuit may receive a voice output signal passed through the band-pass filter and a push button signal from the terminal set simultaneously so that the push button signal can be received even when the voice output signal is transmitted to the terminal set. | |
