Patents by Inventor James W. Lester

James W. Lester 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: 5315644
    Abstract: A circuit for interfacing a host telephone system having a trunk line pair with a central office line pair and an additional circuit line pair includes a loop current monitor circuit for monitoring the host telephone system trunk line pair which is normally connected to the central office line pair. The loop current monitor provides a status signal output indicating the presence or absence of loop current. A relay controller receives the status signal and provides a relay control signal and a hold signal. A relay selectively connects the host telephone system trunk line pair to the additional circuit line pair in response to the relay control signal when loop current is detected after the host telephone goes off-hook. A hold termination circuit receives the hold signal and traps any loop current signals which may be detectable over the central office line pair.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: May 24, 1994
    Assignee: Harris Corporation
    Inventors: James W. Lester, Randall M. Wagner, Randy A. Callaway
  • Patent number: 5289534
    Abstract: A door phone controller has a door ajar feature for alerting a user that a door was left open. The door phone controller accommodates the door ajar feature in several different ways depending upon how it is configured to interface with the central office line. If the door phone controller is configured to interface with the central office line as an individual station, then when a door is left open, the controller alerts the user via auxiliary alert contacts specifically provided for activating a customer chime. When the door phone controller is configured as a ring-down station, the door phone controller alerts the user that the door was left ajar by dialing a pre-programmed telephone number and sending a door ajar tone. If the door phone controller is configured as an interface with a trunk port, then when the door is left open, the controller alerts the user by ringing the trunk line and also energizing the auxiliary alert contacts.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: February 22, 1994
    Assignee: Harris Corporation
    Inventors: James W. Lester, Randall M. Wagner, Randy A. Callaway, Michael Kennedy
  • Patent number: 5164991
    Abstract: An amplified speaker has an amplifier section including an audio amplifier powered from a power input section and a variable audio input section for supplying an input audio signal via an audio transformer to the audio amplifier. The power input section includes a rectifier bridge and a capacitor filter circuit, so that power may be obtained from an inexpensive unregulated AC source rather than an expensive regulated DC power supply. The variable audio input section permits audio signals at various levels from 30 mVrms to 70.7 Vrms to be inputted.
    Type: Grant
    Filed: February 13, 1990
    Date of Patent: November 17, 1992
    Inventors: Thomas J. Johnson, James W. Lester, Dennis P. Damewood