The CD-57 was a mechanical, handheld device derived from the CD-55 and was produced in 1956 and 1957 by the Crypto AG company. A variant, namely the CD-57 (RT), is the same device but it lacks rotors. Instead, it uses a reader for a one time tape. CD-57's were essentially unbreakable provided their one-time, tape system was properly handled and secured. The French, in particular, liked these CD-57's. Weight: 2 pounds.
The CD-57 with cover open (top) and cover closed (bottom). (Photo courtesy John Alexander, G7GCK)
The CD-57 (RT) front view - bottom. (Photo courtesy John Alexander, G7GCK)
The CD-57 (RT) front view - top. (Photo courtesy John Alexander, G7GCK)
|Top view. (E-bay photo)|
|Closeup of cipher wheels and character counter .(E-bay photo)|
|CD-57 rotor #29 showing contact detail. (Photo via E-bay)|
From E-bay "The NATO version of the CD-57 was designated C-1-0. The ciphers obtained with this machine are of the double substitution type and mechanically produced.”.