Patents Assigned to DND Teletronics, Inc.
  • Message registration pulse generator
    Patent number: 4151372
    Abstract: An apparatus for generating message unit pulses for message rate billing which includes means responsive to answer pulse recognition signals and electronic answer supervision from a central office for providing separate and variable numbers of pulses per event based on duration, time of day and distance of call.
    Type: Grant
    Filed: February 16, 1978
    Date of Patent: April 24, 1979
    Assignee: DND Teletronics, Inc.
    Inventors: Fred E. Fitts, III, J. D. Batteas