Electronic Warfare in WW1 by Robert Robinson

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Electronic Warfare in WW1            by Robert Robinson
                                                             On August 4, 1914 Britain opened the telegraph war by
                                                             cutting the German submarine cable that ran from
There is a common misconception that electronic
                                                             Borkum in the North Sea to the Spanish island of
warfare began with the Second World War but, even if it
                                                             Tenerife in the South Atlantic. There was a substantial
was not so labeled, it played a significant part in the
                                                             German research station on the coast of Tenerife and
First World War at both a strategic and a tactical level.
                                                             there were fears (possibly incorrect) that this was being
                                                             used as a cover for espionage and potentially for U boat
Both sides relied on complex cable and wireless links
                                                             support. As Tenerife lay close to the sea routes that
for communication and intelligence gathering on an
                                                             British ships would take to Britain’s West African
international scale whilst, at the fronts, they maintained
                                                             colonies and South Africa, Winston Churchill (then 1st
a complex web of trench and field telephone lines and
                                                             Lord of the Admiralty) ordered the cutting of the
exchanges. It has been said that in 1918 that there were
                                                             communications link.
probably more military telephones serving the Allied
lines on the Western front than there were domestic
                                                             The next step was the remaining German cables
‘phones in Britain, America and France. It would
                                                             running through the English Channel. Many of these
therefore be surprising if the Allies and the Central
                                                             were simply grappled, raised and cut but some (linking
Powers had not attempted to damage each others
                                                             to neutral countries) were patched into the British cable
networks, protect their own, gather intelligence from
                                                             network this providing the Allies with additional capacity
their opponent’ networks and disseminate misleading
                                                             (and in the short term probably intercepting incoming
information through it.
                                                             messages for Germany from the remote terminus of the
                                                             cable). Much of Germany’s telegraph connection to the
The Telegraph War
                                                             world beyond the Central Powers was destroyed.
The electric telegraph played an important role as early
as the American Civil War and by the 1870s most major
                                                             Germany struck back, on 7th September 1914 the
armies had telegraph sections that could lay cables and
                                                             German cruiser SMS Nurnberg, accompanied by SMS
relay messages. In the Franco Prussian War the French
                                                             Leipzig under cover of the French flag approached the
were already deploying portable telegraph sets that
                                                             tiny Pacific territory of Fanning Island. Fanning Island’s
could be strapped to a soldier’s back. The British Army
                                                             only importance was that a submarine cable from
in the 1880s developed a horse drawn limber system
                                                             Canada came ashore to a cable station provided the
that could lay telegraph cable at the gallop. Almost all
                                                             switching capacity to route messages to and from two
armies were still using such equipment in 1918
                                                             connecting cables, one to Australia and the other to
(although many of the cable laying vehicles were
                                                             New Zealand. A landing party from the Nurnberg
motorized).
                                                             wrecked the station and cut the cables (they also found
                                                             time to raid the local post office and steal some
More spectacular was the expansion of the international
                                                             stamps!).
telegraph network, mainly through the laying of
submarine cables (each cable comprising many
                                                             In November 1914 the crew of the German commerce
individual wires). Every major power owned its own
                                                             raider Emden were ordered to destroy the cable station
commercial network of cables, in time of war these
                                                             on Direction Island in the Coccos. This station provided
came under either direct government control or close
                                                             a link between Australia and South Africa. On the
supervision. The technology had also advanced to the
                                                             morning of the 9th the cable station staff saw a warship
point where primitive forms of multiplexer and code
                                                             approaching. Having been warned about SMS Emden
compressors were in use to allow a single wire to
                                                             the station’s wireless operator sent out a message.
handle multiple messages. Switching equipment,
                                                             "Strange warship approaching" and shortly afterwards
although fundamentally mechanical, had become
                                                             "SOS! Emden here" before a German landing party took
complex and expensive. The destruction or damage of
                                                             the station. These messages were picked up by a
an international telegraph station or relay could cause
                                                             passing troop convoy and one of the cruisers escorting
considerable disruption and take a long time to replace
                                                             it peeled off making full speed towards Direction. The
(especially if complex equipment had to be transported
                                                             cruiser was the HMAS Sidney; within an hour and a half
to it by sea). Such stations thus became important
                                                             of battle being joined the burning Emden was beached
strategic targets in time of war.
                                                             on the nearby North Keeling Island. The landing party
                                                             managed to cut one cable and wreck some
Britain with her wide spread empire and trading
                                                             instrumentation before fleeing (they made it back to
interests was particularly vulnerable to damage to the
                                                             Germany after 7 months via the Dutch East Indies and
cable network, she was, however, well placed to protect
                                                             Turkey).
her cables and wreak havoc on those of her enemies.
Germany had a problem as, for geological reasons,
most of her international cables left Europe via the         Telegraph staff under German guard Direction
English Channel. As we shall see later she made some         Island
alternative arrangements.                                     Wireless mast destroyed by Germans Direction Island
The threat of German raiding parties was not lost on         to pick up) when the phone was being used to transmit
other parts of the World. In Canada, troops were             Morse buzzes (as was the case over long lines). As the
despatched to guard telegraph stations on both Pacific       Germans perfected the sensitivity of the Moritz Stations
and Atlantic coasts. In New Zealand the coastal forts,       they could ‘bug’ a phone from a kilometre away.
with their disappearing guns, were manned. However           Moreover, as the signal was transmitted through the
with the destruction of the German squadron at the           ground, by creating underground saps towards the
battle of the Falkland Islands, the loss of the Emden and    British lines they could sit at its end and pick up even
the fall of the port of Tsientao Germany had no naval        more signals. One interesting sidelight to this is that the
force outside European waters that could threaten the        German monitors frequently picked up a whistling noise
international cable network.                                 that sounded like the screech of a descending shell.
                                                             Known as ‘screamers’ these were at one time thought to
Tapping the Telephones.                                      be artificial noises made by British operators attempting
The Western Front was festooned with the wires of            to ‘jam’ the interception; they are now known to have
trench and field telephone and telegraph systems.            been created by the solar wind hitting the ionosphere –
                                                             true signals from outer space.
Field telephone exchange
Although the official British Army instruction was to bury   Once the problem was identified attempts were made to
these at least a foot and a half this was not always         find ways to intercept the German trench telephones by
possible in the heat of an action. Other armies on both      picking up the magnetic induction from operation of the
sides would have the same problem and wires might be         speaker or buzzer. How successful this was is unknown
laid across the open ground, draped across the tops of       as the results were classified and seem to have been
trenches and shell holes, lie under duck boards, be          lost for ever in the labyrinth of military secrecy. At the
tacked along the sides of trenches or even properly          same time a British device called the Fullerphone, the
buried. As the trench line altered with minor advances       invention of a Captain (later Major General) A C Fuller
and retreats some wires might end up crossing from           in 1915, was investigated and then adopted. The
friendly trenches across no mans land through enemy          Fullerphone could send Morse over a 20 mile long
positions and back to ones own side. Where enemy             single wire line and voice over a shorter distance. On
wires were spotted exposed in no mans, land men              some versions of the device it could send Morse and
might crawl out at night and lay wires to tap them. In       voice simultaneously along the same line (effectively
other cases shell fire or even the inadvertent clumsy        what your broadband modem does only it’s much much
boot might break the wires. In some cases, when the          faster). When used on normal phone lines distance was
line was thinly manned or sentries inattentive, wire taps    not a problem. It used a DC signal that was much less
were even laid onto cables in the enemy’s trench. The        powerful than the old trench telephone and therefore
trench telephone and telegraph system on either side         much more difficult for the Moritz Stations to pick up. At
was not secure or reliable.                                  the same time the Morse system depended on a device
                                                             in each phone called a ‘buzz chopper’, the people at
However the British began to get a sense that their calls    each end had to synchronise their buzz choppers, these
were being intercepted with alarming ease. This was          acted as a scrambling device so that no third party
serious as the enemy might, for example, gain advance        could listen in. As a bonus it was found that the Morse
warning of a trench raid or learn when the line was          signals could be transmitted over damaged lines and
thinly manned. However no one could work out why this        across breaks (provided each side of the break was in
was so. It became the common practice not to pass any        ground contact and not too far apart).
important information by the trench phones but to rely
on despatch riders and runners even with the risk of         Fullerphone in use
additional casualties to the messengers. At the same         Like all new devices it took time to roll the new system
time emergency signalling methods such as warning            out but it was in fairly widespread use amongst the
rockets were kept handy as, with the predictably             Allies by the end of the war. More advanced versions of
malignity of inanimate objects, the trench phone would       the Fullerphone system were in extensive use in World
fail just when a call for help was needed.                   War Two.

The cause of the security problem was found by               Wireless Wars
accident when a signals instructor, Sgt Lorne Hicks, on      In 1914 the use of wireless was largely restricted to
a course in Canada found that his phone was picking up       large relatively permanent land installations and ships.
the signal of the man next to him. The British field         The inhibiting factor was both the lack of portability of
telephone relied on a ground return system. In this the      the equipment itself (particularly the receiving units) and
phones are connected by a single wire with the ‘second       the size of aerial needed to have any sort of effective
wire’ of the circuit being a short wire to a spike in the    range. By the end of 1918 wireless sets were in use in
ground. The AC current on the phones was creating a          the front line, in tanks on wireless trucks, from aircraft
signal through the ground that could be picked upon          and even motorcycle mounted.
devices known as Moritz Stations. It was worse (easier
Motorcycle mounted Marconi set
Right from the beginning wireless played an important
strategic role. Germany anticipated the possible loss of
its submarine cables if war broke out and invested
heavily in installing powerful wireless stations in all its
colonies, even the smallest. German commercial
companies were ‘encouraged’ to set up subsidiaries
with large transmitters and receivers in countries that
were likely to be neutral. The United States was the
principal country in which this was done and Telefunken
established a number of stations there (they also
supplied the US Army with wireless equipment).

Telefunken station on Long               owned American Marconi Wireless
Island                                   Company in the United States (after
Powerful stations were established       the war the US government
in Germany the main one being a          pressurised Marconi into selling its
Nauen.. When war broke out and           US operation to General Electric).
Germany lost its cable links it still    As one might expect the staff of the
retained a world wide network of         various      ‘commercial’       wireless
wireless stations. Moreover by           stations contained a number of
wirelessing a German station in the      intelligence officers and other forms
United States messages could then        of spook. They seem to have spent
be put on an international telegraph     quite a bit of time trying to find ways
service there. This was how many         to get around the US censors whilst
messages to and from Mexico and          at the same time monitoring the
South America were transmitted.          enemy’s wireless stations’ traffic so
This was facilitated by a strange        as to be able to accuse them of the
decision made by President Wilson        same thing. Thus at one point the
himself, this was that, whilst to        Marconi Company was hauled up
enforce US neutrality, outgoing          by the US Authorities who had been
radio messages would be subject to       tipped off that the station had
a Federal censor’s approval (to          transmitted a message that might
ensure that they were not of a           help the Royal Navy intercept a
military nature), there would be no      German merchantman that had
control over telegraph messages          sailed from New York (Marconi
carried by cable. Thus a coded           grovelled and promised never ever
message could be received by a           to do it again, and went back and
German       commercial     wireless     carried on as usual).
telegraphy service in the USA and
then taken to an American cable          However it was British intelligence,
service for onward transmission to       cracking the code used for
anywhere in the world without any        messages to and from the German
check on its contents.                   station, that intercepted the German
                                         telegrams to Mexico (inviting Mexico
Radio mast at Nauen                      to attack US territory) uncovered
Britain also invested in wireless        one of the issues that would bring
stations around the world, primarily     America into the war. The same
to service the needs of the Royal        undercover activity would be found
Navy. These were in general not as       in many neutral countries. However
powerful as the German stations as       as many of these joined the Allies in
Britain could rely on the cable          declaring war on Germany (starting
system for long range messaging.         with the US and Brazil in 1917)
Some commercial services were            Germany’s radio network was
also    established    in   neutral      constantly eroded.
countries, indeed the most powerful
radio transmitter in the world (in       Britain wanted the German colonial
1915) was operated by the British        wireless stations closed. They
posed a risk to British shipping as
they could pass on intelligence on      In     Togoland        the     German
merchantmen’s      movements     to     commander abandoned any thought
German commerce raiders and at          of a prolonged guerrilla campaign in
the same time help these (and           favour of protecting fortifications
blockade runners) avoid Allied          around the capital and the wireless
warships. Some of these stations        station (he was still only able to hold
were extremely powerful. For            out for four weeks but even this was
example that in German South West       deemed to by Berlin to be valuable
Africa (today Namibia) could reach      as something like 200 messages
both Germany and South America.         were      transmitted    to    German
Messages could be relayed to other      shipping enabling some valuable
German      colonies   with   lower     cargoes to evade the Allied naval
powered stations and to commerce        blockade). In the Cameroons the
raiders, blockade runners and U         local German strategy abandoned
boats in the South Atlantic and the     the capital and the wireless station
Indian Ocean.                           without a fight in the face of a British
                                        amphibious operation in late
The very first Australian military      September 1914 but held out in the
action of World War One was the         interior until 1916. In German South
landing of a volunteer force in New     West            Africa         wireless
Guinea to eliminate a German            communications were not only
wireless station at Bita Paka near      maintained until the middle of 1915
Rabaul. This was done, even before      but were used by the Germans to
the Australian army could mobilise,     coordinate their resistance to a
at the urgent request of the Royal      British/South African force attacking
Navy.      The     Australians    and   from the south and Portuguese
Japanese quickly occupied those         intrusions in the north. German
German held islands in the Pacific      wireless stations in East Africa
that housed wireless stations.          lasted longer although a British
Germany’s wireless network had          amphibious raid across Lake
started to shrink. When Tsientao fell   Victoria in July 21 – 23rd 1915
the German wireless net in the Far      destroyed the transmitter and masts
East was silenced. The stations in      at Tighe.
the German colonies in Africa took
a little longer. This was in part       The German station at Dar es
because of a difference in priorities   Salaam had been destroyed by
between France, Belgium and             British naval gun fire in August 1914
Britain. Many of the actions in         but was rebuilt. Other stations were
German         colonies      involved   at Mwanza, Bukoba being able to
cooperation between British and         reach the German station at Nauen,
French or Belgian forces. Britain       if atmospheric conditions were right.
wished to be able to advance on         It was not until mid 1916 that the
and shut down the wireless stations     last German wireless transmitting
as soon as possible whereas             station in Africa was silenced. Even
France and Belgium were more            then wireless had not ceased to
interested in the acquisition of        play a part, the German forces,
territory (and to some extent taking    fighting a guerrilla campaign in East
revenge on an invader of their own      Africa carried with them wireless
countries). This sometimes created      receivers that could be used to pick
friction between the two allies, as     up messages from Germany
coordinated actions needed to be        whenever an electrical source was
negotiated. At the same time the        available and there was time to
German colonial defenders were          erect a temporary mast. These were
also split between the desire to        in use right up to the end of the War
prolong resistance in the hinterland    in November 1918.
and preserve territory and Berlin’s
insistence that the wireless station    Codes,        Intercepts       and
be kept operating as long as            Deceptions
possible.                               As the war continued both the Allies
and the Central Powers used               operator who had been previously
wireless      more        and     more    identified as being part of the HQ of
extensively. This process was             a particular military unit was
encouraged by developments in the         detected transmitting from a new
technology that allowed wireless          location then this would suggest
sets to be built smaller but be more      that the unit had also relocated. The
powerful. However wireless has a          volume of signal traffic and any
serious flaw – its signals are            changes in this could reveal a unit
impossible     to     hide.   Wireless    held in reserve being brought up to
intercepts were used as early as          strength and preparing for battle.
August      1914     when      German     The collection and analysis of such
intelligence was able to listen into      data is today referred to as ELINT
wireless        messages         being    (ELectronic INTelligence). As early
transmitted from the Russian Army         as the beginning of 1915 Cartier
HQ in Poland. Amazingly these             could give the French High-
were in clear, no attempt having          Command a complete organisation
been made to encrypt them (the            chart of the German armies, corps
Russian author Solzhenitsyn has           and cavalry divisions.
said that the Russian Imperial high
command somewhat naively relied           A similar system of DF (direction
on transmitting late at night when it     finding) stations was set up round
was assumed that the Germans              Britain in 1916 by a Capt. H. J.
would have gone to bed and not be         Round; these were used to locate
listening!). The intelligence gathered    German ships and proved very
contributed to the German victory at      effective in detecting movements of
Tannenberg.                               the German fleet. The scope and
                                          extent of this network was kept very
A code system was vital to secure         secret and recipients of intelligence
wireless transmission. All the major      gained as a result of its use were
powers began to develop code              not told how it was obtained. Some
systems whilst at the same time           of these stations, suitably re-
listening     to     each       other’s   equipped, were used in WW2 to
transmissions and attempting to           pick up German signals for
break their codes. Networks of            decoding at Bletchley Park and in
listening stations were established,      the Cold War to collect data on
perhaps the most elaborate being          Warsaw pact forces. They might still
that established by the French            be in service today.
under     the     command       of    a
Commandant Cartier with some              Both sides were busy trying to
very tall masts (the Eiffel Tower         break their opponent’s codes. The
being pressed into service to             degree to which they were
provide one of these). This allowed       successful is still unclear and there
even relatively small transmitters in     are conflicting accounts. One
Germany to be picked up and their         reason for this is that if one has
position triangulated and plotted.        broken one’s enemy’s code it is
Even without breaking codes this          wise to conceal the fact for as long
could provide the Allies with             as possible so that he continues to
valuable      information.      France    use it to transmit vital information. If
created a special unit, the 8e            on the other hand you become
Régiment de Transmissions, for just       aware that your enemy has broken
this work. Working under Cartier its      your code it is also a good idea to
HQ was the Eiffel Tower. Every            hide the fact that you know so that
operator tapping in Morse signals         you can feed him misinformation.
had their own style or ‘fist’ by which    British Naval Intelligence was
he could be ‘identified’ even when        seeking a way to pass spurious
transmitting     coded      messages      information to the Germans and hit
(although the French did experiment       on the idea of devising a top secret
with a Morse key that used an oil         wireless code “for the very most
filled relay to smooth out the            important messages only” and then
operator’s own rhythm). If an             engineering a situation whereby
German       intelligence   gathered      ways in which the airship could be
enough information to allow them to       cannibalized to provide much
break the code. A British agent           needed equipment. On the 21st
travelled to Holland in the guise of      November 1917 L59 rose from the
an official visiting the embassy          Bulgarian airfield of Yambol to make
there. He stayed in a hotel known to      its long flight to the Makonde
have Dutch staff, in the employ of        plateau. The L59 had successfully
German intelligence, who would tip        crossed the Mediterranean and
off a resident agent. The ‘official’      Egypt and was well beyond the
went out, ostensibly for a night on       range of any Allied fighter bases
the town, leaving a locked attaché        when on the 22nd of November
case in his room. This contained          while passing Khartoum a wireless
papers with enough information to         message ‘from Berlin’ informed its
allow an experienced code expert to       captain that the German forces in
create his own code book. Covert          East Africa had surrendered and he
surveillance observed that the room       should abort his mission and return
was entered the attaché cases lock        to base. L59 flew back to Bulgaria
picked and a series of photographs        covering 4,220 miles and being
taken. Thereafter this code could be      airborne for 95 hours. The wireless
used as a direct channel to pass          signal had not come from Berlin and
misinformation mixed in with              von Letow was still fighting. The
genuine but relatively harmless           message had been sent from an
messages. As only British Naval           Allied ‘spoof’ station, just one
Intelligence         and     German       example of WW1 electronic warfare
Intelligence had copies of the code       albeit a most effective one.
book there was no danger of any
messages being picked up by and           L59
confusing any British warships.           Zeppelins raiding Britain used radio
About a year later Naval Intelligence     signals as a navigational aid and
used a double agent to sell an            both British and French stations
update of the code book to the            attempted to jam these by
Germans. Even to this day some            transmitting on what they assumed
histories    state     that  German       would be same frequencies. It was
Intelligence broke the most secret        then found that the German aircrew
British naval wireless code, which        were       using      the      French
was what British Naval Intelligence       transmissions from the Eiffel Tower
had wanted people to think at the         to provide fixes. On the night of the
time.                                     19/20th October 1917, during a
                                          major Zeppelin raid on Britain,
There also appears to have been           transmissions from the Eiffel Tower
some use made of                ‘spoof’   were switched to another station.
transmissions –wireless messages          The effect was to give the German
purporting to have come from              navigators       completely       false
friendly stations but actually sent by    bearings. The returning Zeppelins
a hostile one. In 1917 the super          were all badly off course, two
Zeppelin L59 was prepared for a           ending up in the South of France,
long range, one way, supply               and five were destroyed or
mission to German forces, under           captured. The use of wireless to
von Letow, still fighting in East         mislead was kept quiet (after all the
Africa. It would carry 30,000 pounds      Allies might want to do it again). The
of ammunition, weapons, medicine          weather was bad that night with
and bandages, materials and               strong winds; this was given out as
sewing machines for new uniforms,         the reason for the disaster (and may
mail, binoculars, spare rifle bolts,      have been a contributing factor).
spare machine gun barrels, bush           Even today a number of books on
knives, spare radio parts and a           the Zeppelin raids fail to report the
crate of wine. Part of the material of    impact of wireless.
the outer envelope was replaced
with tent fabric and considerable                                   ******
thought had been given to other
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