Aerospace and Electronic Systems Magazine March 2017 - 21

Giannetti
formed during daylight, i.e., the most unfavorable conditions
for radio propagation. Further tests were carried out in the night
at 12:00 a.m. and gave even better results. On the evening of
the next day, Marconi himself attended a final session of tests
in Coltano, in the presence of the King Vittorio Emanuele III.
Massawa station acknowledged the reception of the test signal,
and sent back a wireless telegram to Coltano using a carrier
wavelength of 6000 m (50 kHz) [21]. That evening, Gino Montefinale4 (Figure 10), then a young IRN officer and a brilliant
radio engineer, was on a ship in Massawa's harbor and noted
in his diary [22] that the high pitched hiss and the purplish
lightning generated by the transmit equipment were clearly detectable from a distance of 2 km! At the end of the tests, the
King enthusiastically congratulated Marconi on his outstanding
achievement.
One year later, on Nov. 19, 1911, again in the presence of the
King, Marconi successfully inaugurated the station by sending
the following telegram to the Director of the New York Times:
"My best greetings transmitted by wireless telegraph from Italy
to America. G. Marconi. Pisa 5.47 p.m." [13]. The message was
transmitted from Coltano to Glace Bay (Canada), and was relayed
to New York via land lines. Another telegram was sent to Clifden
station (Ireland), 1850 km away. The acknowledgment of message reception was sent back to Coltano via land and submarine
cables. A report on these inaugural transmissions can be found in
the newspaper excerpts collected in [3, pp. 110-112]. Then, at 2
a.m. of Nov. 20, 1911, a further telegram was sent to Massawa. In
this way, the Coltano station became a sort of "gateway" providing
interconnection between the wired telegraphic network connecting
mainland Italy and its African colonies. Transmission experiments
terminated at 6 a.m. and were all successful, despite the unfavorable weather conditions [23].
In a speech held in Rome in 1914 about the progress of radiotelegraphy, Marconi said that, "even though the station in Coltano
had not yet installed the latest improvements in radiotelegraphy
particularly appropriate for commercial communications, the signals of that station were clearly received within a range of about
5000 km." [24]. Some remarkable records set by Marconi's Coltano station are listed in Box 4.
In September 1912, Marconi went to Pisa and visited again the
radio station in Coltano; there he met the King and was his guest
in the nearby San Rossore royal estate. On Sept. 25, 1912, Marconi left Pisa driving his FIAT 50 HP towards Genoa. In Borghetto
Vara, near La Spezia, he had a terrible crash with another car. He
was badly injured by windshield fragments from his car and lost
his right eye (further details on this accident are reported in [3, pp.
137-138]).
Right after the inauguration, the management of the Coltano
radio station, which meanwhile got the call sign ICI, was handled
by the IRN and this opened a new era for the Coltano station.
4

Gino Montefinale (1881-1974) was an Italian admiral of the
IRN, a radio pioneer and a writer. He is renowned for his active
collaboration and friendship with Guglielmo Marconi. In the
early 1930s, he designed a renovation of the Coltano transmit
site in cooperation with rear admiral Giuseppe Pession, another
eminent IRN scientist.

MARCH 2017

Figure 9.

Aiming of VLF colonial (top) and continental aerials (bottom).

Figure 10.

(a) Admiral Gino Montefinale (1881-1974). (b) Professor Giancarlo
Vallauri (1882-1957).

GROWTH AND DEVELOPMENT OF COLTANO STATION: THE
VALLAURI'S ERA
Despite the successful inauguration and the effective support to
the IRN during Italian military operations in Africa (1911-1912)
and during WWI (1915-1918), the Coltano station did not meet
the expectations in terms of reliability for regular intercontinental
service.

IEEE A&E SYSTEMS MAGAZINE

Table of Contents for the Digital Edition of Aerospace and Electronic Systems Magazine March 2017