Patents by Inventor John Bush

John Bush 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).

  • Patent number: 3979679
    Abstract: An improved squelch circuit for FM demodulators including a low pass filter for filtering out-of-band noise from the demodulator output signals, a delay line for time delaying the filtered signals, a gate for selectively passing the filtered demodulated output signals to an output terminal, and a control circuit for controlling the gate. The control circuit includes a high pass filter for passing the out-of-band noise in the demodulated signals, a detector for detecting the noise level of the noise passed by the high pass filter, and a comparator for comparing the detected out-of-band noise level to a reference to develop a gate control signal which causes the gate to be opened when the out-of-band noise level is relatively low and to be closed when the out-of-band noise level is relatively high.
    Type: Grant
    Filed: June 30, 1975
    Date of Patent: September 7, 1976
    Assignee: California Microwave, Inc.
    Inventors: John A. Bush, Drew R. Lance, John E. Altstatt