Patents by Inventor John I. Stahl

John I. Stahl 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: 5138650
    Abstract: A method of handling a charge authorization in a cordless phone (12) is provided wherein a memory (53) in the cordless phone (12) is credited (634) by a value representing a purchased amount prior to a usage of the cordless phone (12). The usage of the cordless phone is allowed (420) depending on that value which is debited (522) during the usage of the cordless phone.
    Type: Grant
    Filed: September 27, 1990
    Date of Patent: August 11, 1992
    Assignee: Motorola, Inc.
    Inventors: John I. Stahl, David L. Brown, David R. Heeschen, Robert L. Breeden, Richard E. Bessom, Frank E. Lambrcht, Mark S. Stuglik
  • Patent number: 4947420
    Abstract: A selective call communication system for use by an untrained person is provided. The communication system includes a number of telephones located in different locations, connected to a central switching unit. A number of selective call radios, each having an address, are assigned to the central switching unit. Upon the use of the telephone, the central unit identifies the telephone in use, and initiates an alerting call to the corresponding selective call radio automatically. The selective call radios may be pagers or two-way radios. Other features such as radio to radio communication, and radio to telephone network communication may be incorporated into the system.
    Type: Grant
    Filed: April 28, 1989
    Date of Patent: August 7, 1990
    Assignee: Motorola, Inc.
    Inventors: John I. Stahl, David J. Michalak, Klaus Knapp
  • Patent number: 4630035
    Abstract: An alarm system for sensing an alarm condition within a relevant alarm area includes one or more portable alarm units for sensing an alarm condition. Each alarm unit includes a radio frequency transmitter for identifying the alarm unit and a secondary, audio, transmitter for defining the relevant alarm area. The system also includes a plurality of transponders. Each transponder includes a primary receiver for receiving a radio message from an alarm unit and a secondary receiver for receiving an audio signal from the alarm unit. A real-time clock in each transponder provides the elapsed time between receipt of a primary and receipt of the secondary alarm signals. The alerted transponders then transmit to a control unit a transponder address code, an alarm unit identification code and an elapsed time indicia. Based on the address code or codes and the minimal elapsed times detected by the control unit, the relevant alarm area can be determined.
    Type: Grant
    Filed: January 4, 1985
    Date of Patent: December 16, 1986
    Assignee: Motorola, Inc.
    Inventors: John I. Stahl, Burton J. Fischel, Frank J. Will