involving removable or interchangeable coding members, e.g. master tapes, punched cards

Full Title

Typewriters for ciphering or deciphering cryptographic text > wherein the operative connections between the keys and the type-bars are automatically and continuously permuted, during operation, by a coding or key member > involving removable or interchangeable coding members, e.g. master tapes, punched cards

Classification Context

Section:

PHYSICS

Class:

EDUCATING; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS

Subclass:

CIPHERING OR DECIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHER PURPOSES INVOLVING THE NEED FOR SECRECY