Patents Assigned to Terence H. Leather
  • Communication system
    Patent number: 4885797
    Abstract: An audio signal and a selected one of a plurality of sub-audio tones are transmitted to a plurality of receiving each being capable of being conditioned by first, second or third selected sub-audio tones so that either all receivers, or only a select group of all of the receivers or only an intended group are the receivers accept the transmitted audio signal, there being as many selectable second sub-audio signals as there are groups and as many selectable third sub-audio signals as there are receivers.
    Type: Grant
    Filed: June 2, 1988
    Date of Patent: December 5, 1989
    Assignee: Terence H. Leather
    Inventors: Terence H. Leather, Frank R. Naylor, Paul S. Gradwell