Patents by Inventor Renald A. Ratti

Renald A. Ratti 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: 4182934
    Abstract: Certain telephone calls cannot be billed properly due to the failure to detect a valid answer signal from the called customer. This disclosure presents an arrangement for detecting irregular calls that are recognized initially by a momentary off-hook signal from the called end of the trunk which is not quickly followed by a release of the trunk. When a momentary off-hook signal is received, the holding time of the trunk is measured. If the holding time exceeds a predetermined threshold a record is made of the lines connected to the trunk.The calls are also categorized by called destination to detect fraudulent calls which are frequently directed to selected destinations.
    Type: Grant
    Filed: September 26, 1978
    Date of Patent: January 8, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Charles T. Keys, Renald A. Ratti