American Cryptology during the Cold War - The Black Vault

For tactical use, the Army used a modified Hagelin machine called M-209. It was
small and light, and being completely mechanical, it required no electricity, which made it
ideal for foxhole use. But it was difficult and time-consuming to set up properly.
(Nonetheless, it continued in use into the early 1960s.) Smith-Corona produced it in huge
quantities for $64 a copy - one former NSA official estimated that some 125,000 devices
were built before it went out ofproduction. 44
The wartime machines were, with two exceptions, off-line devices. One typed the plain
text of the message on a keyboard, and the machine produced cipher text on (usually) a
sticky-backed tape which could be glued on a paper and taken to the communications
operator for transmission.
To handle the increasing volumes of messages, what was needed was a machine that
could convert plain to cipher text on-line. SIS devised a solution early in the war. Called
SlOCUM (Converter M228), it was not as secure cryptographically as SlGABA, and a new key
setting was required for every message. As a result SlOCUM was used in only limited
numbers. 45
A different sort of on-line machine was the SlGTOT, which used a one-time tape. Onetime
tape machines became known generically as Python systems because ofthe huge coils
of cipher tape that they required. Python systems were used until the early 1960s, but
they were cumbersome because of the enormous quantities of tape that had to be
generated, handled, and fed through the TD (transmitter-distributor), They were not the
long-term answer. 46
SIGTOT
(Note the paper tape threaded from the right·hand
spool across the center ofthe machine through a perforator.)
IhUf9bK VIA 'FAbKW~K:KYII9bK 69MHf'F 69ti'FR8b S'iS'fBMB d6IN'ff:H
NOT RELEASABLE TO FQR~.il8nlHrTIONALS
213