Patents Represented by Attorney J. A. Crawford

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  • Amplifier circuit for increasing transmit and receive levels in a telephone hybrid network
    Patent number: 3963876
    Abstract: A telephone amplifier circuit comprising a transmit amplifier and a receive amplifier provides gain in both the transmit and the receive directions. Loss is voice-switched into the receive amplifier in response to the sum of the transmit and receive speech levels to provide sidetone and gain control.
    Type: Grant
    Filed: June 30, 1975
    Date of Patent: June 15, 1976
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Roger Edward Holtz, Roger Allen Radosevich