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Ottico Meccanica Italiana

Ottico Meccanica Italiana, or OMI, was an Italian manufacturer of photogammetric equipment, founded in Rome (Italy) in 1926 by Umberto Nistri. After Umberto's death in 1962, the company was led for nearly 20 years by his son Raffaello after which it became part of the Italian helicopter manufacturer Agusta. It is little known that, at the start of WWII, OMI secretly produced an electromechanical cipher machine, similar to the German Enigma, for the Italian Armed Forces. Newer variants of this machine were produced after the war, from 1954 until the early 1960s.

 History of OMI

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OMI cipher machines on this website
OMI Alpha, the first OMI cipher machine (1939-1940) OMI Criptograph, the post-war model (1954) OMI Cryptograph-CR (1958)
OMI Cryptograph-CR Mk II (1960)
At present we know of the existence of four different models of cipher machines made by OMI-Nistri during and after WWII. Although very little information about these machines is available in the public domain, we have tried to give a detailed description of each model. This was only possible with the kind cooperation of collector Günter Hütter in Austria, who has acquired a Cryptograph-CR Mk II in 2013 and allowed us to photograph it and measure the wiring.

Other information has been taken from an NSA report that was declassified in 2014. If you have any additional information, please contact us. Crypto Museum would very much like to add an OMI cipher machine to its collection. If you have a surplus machine available, or if you know of a machine that might be available, please contact us.

OMI Alpha   wanted
At the outbreak of WWII, OMI's regular business came to a halt, but the company survived as they had secretly developed a cipher machine for the Italian Armed Forces: the OMI Alpha.

The machine is very similar to the Zählwerk Enigma and features five cipher wheels with irregular stepping and a moving reflector.

 More information

OMI Alpha

OMI Criptograph   wanted
In 1954, after OMI had recovered from the war, the successor to the OMI Alpha was developed: the Criptograph, again primarily intended for use by the Italian Armed Forces, but also offered to other users.

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Cryptograph CR   wanted
In the late 1950s, probably around 1958, the Cryptograph-CR was introduced as an improved version of the Criptograph of 1954. Apart from some manufacturing changes and a new power supply unit, this machine was largely identical to its predecessor.

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OMI Cryptograph-CR

Cryptograph-CR Mk II   wanted
As the Cryptograph-CR was a complex machine with high electric currents flowing through the contacts of the switches of the keyboard, the Cryptograph-CR had reliability problems. Some of the machines were therefore upgraded with 26 electric relays during the early 1960s.

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OMI Cryptograph-CR Mark II

Further information
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Crypto Museum. Created: Sunday 20 December 2015. Last changed: Saturday, 24 February 2018 - 14:06 CET.
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