Patents by Inventor Klaus Walla

Klaus Walla has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Speech-controlled loudspeaker telephone station circuit
    Patent number: 4315103
    Abstract: A circuit arrangement for a speech-controlled loudspeaker telephone station incorporates a pair of operational amplifiers for receiving voltages proportional to the microphone voltage and the loudspeaker voltage, and apparatus for rectifying and comparing the output voltages of the operational amplifiers, to supply control signals for selectively controlling operation of attenuators in the transmitting and receiving channels.
    Type: Grant
    Filed: September 7, 1979
    Date of Patent: February 9, 1982
    Assignee: Siemens Aktiengesellschaft
    Inventor: Klaus Walla
  • Power circuit for loudspeaker telephone
    Patent number: 4304969
    Abstract: A power circuit for a loudspeaker telephone station incorporates separate capacitors across the power terminals of the transmitting and receiving amplifiers, with a regulating circuit for charging the capacitor connected across the receiving amplifier only after the other capacitor has been fully charged. A control circuit for the telephone station is connected in parallel with the transmitting amplifier.
    Type: Grant
    Filed: September 7, 1979
    Date of Patent: December 8, 1981
    Assignee: Siemens Aktiengesellschaft
    Inventor: Klaus Walla