McFiggins Robert B, Eckert Jr Alton B: Remote postage meter resetting method. Pitney Bowes, Soltow Jr William D, Scribner Albert W, Wittstein Martin D, February 12, 1974: US3792446 (113 worldwide citation)

A data center equipped with a programmed digital computer and a voice answer-back unit processes telephone calls from users of postage meters equipped with combination locks, wherein each lock inhibits recharging of its associated meter with an additional postage increment while locked and its combi ...

Remote postage meter resetting method and system. Pitney Bowes, December 17, 1975: GB1417872-A (2 worldwide citation)

1417872 Electric selective signalling PITNEY-BOWES Inc 15 Nov 1973 [4 Dec 1972] 63131/73 Heading H4K [Also in Division G4] Postage meters 24 connected to a data centre 12 are equipped with locks 26 having combinations which vary in pseudo-random manner, the combination required at any time to unlock ...