Page 281 - The Secret War in the Italian front in WWI (1915-1918)

CHAPTER TWELVE

The analysis of traffic confirmed a persistent imbalance between the German and Austrian
networks due to the larger number of the German stations and to the different approaches of the
two Armies in radio usage. Only the Austrian navy relied on frequent radio transmissions, in some
circumstances . In November, the stations of the Section intercepted an average of 23 dispatches
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per day with a maximum of 40, with a ratio between dispatches originating from the German and
Austro-Hungarian networks larger than 4 to 1.
It is well known that two or more radio-goniometric stations working in parallel can locate enemy
transmitters, relying on direction of emissions found by each station which nevertheless could
report its results in worksheets like the one drafted by the Asolo station and shown in picture 12.4
where the almost illegible red dots around the centre indicate the “stations with Austrian service
standards” .
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The Austrian field stations, after a moderate activity in November, transmitted only on some rare
occasions during the first half of following month. On the contrary, the German field radio traffic
was still intense until the middle of December, when it started to gradually disappear, confirming the
belief that the German divisions were moving from the Italian to the Western front . Conversely,
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the radio silence among the Austro-Hungarian ranks was ascribed to the “reduction in service
provided by field stations since all communications between higher commands were relayed by
wire”. However, the naval stations along the coast. from the Falconera port near Caorle, to the bay
of Panzano in the Gulf of Trieste, remained still active .
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ausTrIan and gerMan codes
The report drafted by Section R of the Intelligence Service and sent to the Allies in May 1918,
described some Austrian codes “used after November 1917” . In spite of the scarcity of available
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intercepted material, the Cryptographic Unit broke, as already mentioned, at least seven codes
employed by the Austrian army until April of the following year. One significant pieces of
information in that document concerned “two codes used at the Piave front in November 1917,
namely the Stern for service communications and the CW code for military messages”.
The same report included the coding and decoding parts of the Stern, together with a sample
of a decrypted Austro-Hungarian cryptogram both shown in Annex B (pictures B.3 and B.4).
The Italians nicknamed Stern (German for “star”) after the the separator between words in the
encrypted dispatches . Very similar to the Stern was the Tunis code used in Bessarabia, which
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only differs from the former for the 5-letter codewords. The word ‘tunis’ had the same function as
‘stern’ in the previous code.
The codes that the Italians labelled as CW and Carnia, each having 1,000 entries, were probably
adopted from October/November 1917, when the Austro-Hungarians also “switched to the
codes” . David Kahn, making this statement, obviously referred to service and field codes, since
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rd
st
67 3 Telegraph Operators Regiment, 1 Radio-Goniometric Section, Bollettino N° 4, op. cit. p.2.
68 The picture shows that the Austrian stations, unlike the German’s, only seemed active in exceptional circumstances, that is,
immediately before and after the most significant attack actions between 9 and 27 November.
st
69 3 Telegraph Operators Regiment, 1 Radio-Goniometric Section, Bollettino N° 4, op. cit., p. 4 - 21.
rd
70 ibid. p. 21.
71 General Headquarters, Intelligence Service, Section R, Notes on radio Telegraphy, op. cit.
72 The code groups of the Stern known to the Cryptographic Unit correspond to 84 one-letter, two-letter, or three-letter
plaintext groups and include pronounceable five-letter words, from “adele” to “wirth”, or two digits between 15 and 99. In
the latter case, a third digit often precedes these two.
73 D. Kahn, op. cit., p. 319.

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