Patents Assigned to Tel-Tech Devices, Inc.
  • Pay telephone monitoring system
    Patent number: 4736444
    Abstract: A passive, non-intrusive pay telephone monitoring system is disclosed for maintaining a talley of the amount of money present in a money box. A signal is sent over the line, interconnecting the pay telephone with its central office equipment when money in the box is collected by a collection agent, and the collected amount of money and the time of collection are then stored for verification of the collected amount.
    Type: Grant
    Filed: February 14, 1986
    Date of Patent: April 5, 1988
    Assignee: Tel-Tech Devices, Inc.
    Inventor: Robert Dhein