Abstract: An apparatus for automatically cancelling bank notes comprises an ink jet printer which provides cancellation markings on bank notes in contactless fashion. A marking sensor which checks the presence of the markings is protected, along with the ink jet printer, against unauthorized access.

Abstract: A card-encoding system and method preserves the security of the encoding process against duplication and counterfeiting of cards by securing the interactions under the control of the individual and then of the issuing institution. Multilevels of offset codes are generated in successive interactions so that attempted alteration, duplication, or counterfeiting of a coded card will be readily detectable using "off-line" card-checking apparatus. An "active" card is initially issued or authorized with an established credit balance, and its authenticity, balance, and proper use are continuously checked, debited and updated in each authorized transactions completed by the proper individual. A card or other data-carrying medium may be verified as authentic and unaltered, and the identity of an authorized individual assigned to the card may be verified by initially recording an offset on the card and by subsequently comparing the recorded offset with an offset regenerated from the same data used initially.

Abstract: In a method for chasing game, a set of portable sound generators are set out in the field in accordance with a predetermined pattern for chasing the game in a predetermined direction when the sound generators are actuated. Each of the sound generators has a clock associated therewith and means for setting the turn-on time to an accuracy of plus or minus at least a few seconds, such that precise timing of the turn-on time of respective ones of the sound generators is settable, as desired. The turn-on times are then set in accordance with the positions of the respective sound generators in the predetermined pattern so that the sound generators turn on in a predetermined sequence for chasing the game in the predetermined direction.