Photo by David Friend Productions, San Diego, California


11-004. Swedish, early 1950's, manufactured by AB Transvertex and probably used by Swedish military forces until the early 1970's. The machine was designed for relatively low level military use - platoon, company, up to battalion levels and in regimental and brigade staffs. It embodied some new ideas in mechanical cryptography with alleged high resistance to cryptanalysis. The HC-9 used a reading mechanism for punched cards instead of pin wheels such as those used in Hagelin machines of the period. An easily replaceable card inserted in the machine forms the interior "setting." The card then guides, via a special adding mechanism, a drum that is equipped with 16 mixed alphabets (also replaceable) which appear, one for each ciphering stage, in a reading window in a sequence that depends on the way the card is punched. The mixed alphabets are then read against a consecutive (ordered) alphabet. See pages 251-265 in CRYPTOLOGIA Volume XIII Number 3, July 1989 for a detailed article on the HC-9 by C.A. Deavours and Louis Kruh.

This HC-9 is in very fine overall condition and comes with copies of the Operation Manual and the manufacturer's descriptive brochure (both in English), with alphabet sheets, internal key punched card, and the original rubber carrying case; however, the alphabet sheets and key card are facsimiles as the originals were destroyed by the Swedish government when the HC-9's were declassified.


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