by Bartholomew Lee

World War One wireless intercept services:

By 1914, radio communications, or wireless telegraphy as these communications were then known, were used by the world's military and naval forces. The relationships of frequency or wavelength, power, directivity and range were not well understood. Signals officers and commanders in the field and at headquarters rarely took into account the possibility of interception, or deception. The troops and sailors of the European nations soon bore the costs of such negligence.

In 1914 British radio operators organized as the basis of the Royal Navy radio intercept service, feeding traffic to Admiralty Room 40 for cryptanalysis and providing the foundation for the World War One success of British Intelligence:

Maurice Wright became a Marconi engineer in England in 1912 (and was later Engineer in Chief). Wright experimented with the then new triode vacuum tube in a radio receiving circuit in 1914. Two days before the outbreak of hostilities in August of 1914, he received German wireless traffic. He worked with Captain H. J. Round, (later a colleague and supporter of Major E. H. Armstrong after America entered the war). Their circuit details are lost to time, but it was undoubtedly a regenerative configuration, for it "made the interception of long range communications possible for the first time" as later reported by Peter Wright, Maurice's son, later a high official in the British Counter Intelligence Service (MI-5). (Peter Wright, SPYCATCHER (Dell, New York, 1988, ISBN 0-440-20132-2) at p. 10).

Working at his lab at Marconi at Chelmsford, Wright realized he was listening to the German Navy. He got the intercepts to Captain Reggie Hall of Naval Intelligence. Hall realized the bonanza in his hands, and put Wright to work building a chain of intercept stations for the Admiralty. (Ibid.) Wright and Round also developed aperiodic direction finding techniques to track the German fleet, proving sufficient warning for the British fleet to engage it on the high seas. In the process, Wright established a clandestine intercept station in Norway in 1915. (Ibid.)

The intercept stations set up in this effort were known as the "Y" stations. Marconi receiving stations, British Post Office stations and an Admiralty "police" station all provided intercepts to Hall's Room 40 codebreakers. These stations were soon joined by enthusiastic amateurs. Barrister Russell Clarke and Col. Richard Hippisley had been logging intercepts of German traffic at their amateur stations in London and Wales. They so reported, and went to work for Hall. New intercept stations soon went up on the coast. Soon practically all German naval wireless traffic also found its way to Room 40. (Patrick Beesly, ROOM 40, BRITISH NAVAL INTELLIGENCE, 1914-1918 (Harcourt, Brace, Jovanovich,New York, 1982) at p. 13-14; Nigel West, THE SIGINT SECRETS, (Morrow, New York, 1986, ISBN 0-688-07652-1) at p. 57ff).

The German high power long wave station at Norddeich provided fodder for the codebreakers through the Y stations, which also soon turned to higher frequency interception as well. (Ibid, 14-15). In 1915 these intercepts helped the British to win the naval battle at Dogger Bank, and played vital roles in later naval engagements.

The direction finding stations working under Round also provided intercepts to Room 40. (Ibid. 70). The directionals tracked U-boats and Zeppelins as well as naval craft. (Ibid.). (from SIGINT, p. 71).

Interior shot of a DF position. This was a French set used for training at the II Corps Signal School in France.

The Y station intercepts showed that the 1915 sinking of the Lusitania had the approval of the German high command, despite its denials. (Ibid. 109-111).

The leading history of the astonishing success of British intelligence in the First World War concludes: "[the] Y stations made it all possible." (Ibid. 315). The most famous intercept of all was the infamous 1917 Zimmerman Telegram that brought America into the war. Germany promised Mexico it could have back the territory it lost in the Mexican American War, if it would join Germany against the United States. (see Barbara Tuchman, THE ZIMMERMAN TELEGRAM (Macmillan, New York, 1958). Snatched from the ether by intercept stations and decrypted by Room 40, it enraged Americans. (SIGINT, 88ff, ROOM 40, 125ff). Captain Reggie Hall of Room 40 claimed "Alone I did this."

As early as November, 1914 there had been a call in the British press for the use of private wireless stations to monitor for spy transmissions out of England. (SIGINT, 46). While there is no evidence ofany wireless transmission of espionage out of England in that war, the demand of the amateur radio fraternity to be useful was met, and the system that would be so effective in the next war was foreshadowed.

The British Navy successfully intercepted wireless messages on the high seas as well. In an outstanding feat of codebreaking, Signal Officer Charles Stuart of the cruiser Glasgow determined that the German cruiser Dresden would coal at Juan Fernandez Island (Robinson Crusoe's old second home) off Chile, from deciphering an intercept from the Nauen Telefunken station (Ibid. 78).

British intelligence also sent Sir Hercules Langrishe and A.E.W. Mason to destroy the German station in Mexico at Ixtapalpa in 1918. This Mason did by smashing its Audions, putting the German agent Herr Jahnke out of business. (Ibid, 190, 241-42).

The success of British Army signals units in intercepting German wireless traffic convinced British commanders that wireless was too dangerous to use. The signals units thus turned almost exclusively to monitroing and intercept work. (SIGINT, 54)

Imperial German army interception of Russian wireless traffic leads to the decisive German 1914 victory at Tannenberg, blunting the Russian advance west:

The Russian Army used wireless to coordinate its campaigns. It took perhaps no precautions against interception and did not encode its traffic. In 1914, the Germans won the decisive battle of Tannenberg against the Russians. The Germans had all of the Russian traffic in hand and readable, overheard by the German radio station at Thorn, and in Koenigsberg in East Prussia. While the Germans may not have made as much use of this traffic as its importance would dictate, Generals Paul von Hindenberg and Erich Ludendorff could and likely did know as much about what the Russians would do as they did themselves. (David Kahn, HITLER'S SPIES (Macmillan, New York, 1978, ISBN 0-02-560610-7) at p. 35). Tannenberg showed how important intercepts could be, and the Germans set up wireless intercept stations on all fronts. Yet the intercepts had gone to Hindenberg by motorcycle at the personal initiative of the chief of the Thorn station, and the whole effort began as an amateur and even sporting endeavor of the operators with time on their hands. (Wilhelm F. Flicke, WAR SECRETS IN THE ETHER (National Security Agency, 1954) at p. 13).

Tactical intercepts by all belligerent signal services provide important battlefield intelligence, but radio deception becomes a weapon:

In early September, 1914 the Russians intercepted a message from German Army Staff Headquarters from which the Russians inferred a threat from a new large force, and therefore held back forces of their own in the upcoming battle. The German Eighth Army staff, however, anticipating interception, had transmitted in plain text from its station at Koenigsberg the completely false message. (Flicke, 12). Radio deception thus began to play its counterpoint to radio interception at the commencement of the festivities. The Germans used radio deception again successfully within weeks.

The Battle of Tannenberg taught the Germans the value of their nascent intercept efforts. The Russian traffic was read from August 1914 to the close of 1915. OneRussian General officer termed the Russians use of plain text and failure to take precautions "unpardonable negligence." (Flick, 10). The Austrians had integrated their intercept service into their Chancellery cryptographic section at the beginning of the war. (Flicke, 14). They regularly intercepted and decrypted Russian traffic all throughout the war.

The Germans made in the West the very errors from which they profited in the East. The French even before the war strove to intercept relevant traffic. At the beginning of the war in the West, the Germans sought to thrust into France to defeat the French armies east of Paris. The French had the whole order of battle by radio intercepts, and up to the minute tactical intelligence. Just as the Russian thrust failed in the East for want of radio discipline, so to the German thrust in the West turned to defeat at the Battle of the Marne for exactly the same reasons. (Flicke, 32ff).

After these failures to achieve early decisive victories, the war degenerated into trenches, artillery and gassing, for four horrible years. The superior material and manpower of the allies, with the entrance of the United States in April, 1917, turned the tide. The United States also joined the war in the ether. In 1918, the U.S. Army Signal Corps established its first long range intercept station in Maine, to listen to Europe, under Lt. Arthur E. Boeder. (James Bamford, THE PUZZLE PALACE, (Houghton Mifflin, Boston, 1982, ISBN 0-395-31286-8) at p. 155). American "Y" stations (although that was only the British nomenclature) monitored Nauen's transmissions to German agents in Mexico and South America. (ROOM 40, 248). The U.S. Army had used mobile intercept stations as well as land stations as early as 1916 on the Mexican border, and well into the 20s. (See Lee, America'sWireless Spies, 5 Antique Wireless Association Review 21 (1990)). Army Intelligence brought its pre-war expertise with it in the American Expeditionary Force (AEF) to France. "Radio intelligence firmly established itself as an Army intelligence tool in France. In addition to monitoring U.S. traffic for security violations, Signal Corp intercept stations located all along the enemy front copied enemy traffic and pinpointed the location of enemy positions by goniometric radio direction finding. Intercepted traffic was passed to radio intelligence sections at General Headquarters and with the two field armies, where specialists analyzed message flow patterns and attempted to decrypt the messages themselves."

Illustrations appear nearby of a U.S. Army mobile stations in France and a French training station (from MI). Also nearby is a photo of an Army station in France with G.S. Corpe standing in the middle behind the operator. Mr. Corpe had been an early (1912) United Wireless operator at Avalon on Catalina Island off Los Angeles, the first American circuit to handle paid wireless traffic some 15 years before. He captioned this photo:

"U.S. Signal Corps Army Receiving Station France, 1918. W6LM in center, standing with Head Phones. Close to where Major Armstrong developed Super Het Circuits."

Between the wars:

Downsizing was the aftermath of the Great War's end, as it is of all wars. Intercept services and intelligence functions shrank. There were, however, soon untoward "consequences of the peace" (to use Lord Keynes' phrase). As wireless and radio came to play a part in the unfolding events, so did radio interception.

The Brittish continue to monitor and decrypt, especially Soviet subversion in the 1920s.

At the close of the First World War, the allies turned their attention not only to the nations of the world, but also to the subversion worked by the international communist movement. With the success of the Bolshevik Revolution in Russia in 1917, all of the Great Powers faced a new threat, revolution from within. The military intelligence services also monitored the communications of the Reds. Nearby is photo of a U.S. mobile intercept station at work in Germany after the end of the war.

The Germans themselves valued their military intelligence section, which was re-instituted on a permanent basis in 1919 (David Kahn, HITLER'S SPIES (Macmillan, New York, 1978, ISBN 0-02-560610-70 at p. 41). Within Germany itself, the Free-corps set up a monitoring station to listen to communists. The official German intercept service concentrated on the international press radio service to 1925, gradually turning its attention to diplomatic transmissions (Flicke, 89).

In the estimation of a German authority, the English had the superior radio intercept service between the wars, devoted not only to military intelligence but also to diplomatic traffic (Flicke, 100). The French also maintained their intercept service, as did other nations. The Russians maintained the best discipline and were perhaps the most effective. The Poles more than held their own. The Italians ran a lax operation, and other nations had only indifferent success. (Ibid).

In October, 1919 the English organized the Government Code and Cipher School (GCCS) amalgamating Room 40 of the Admiralty and Military Intelligence. To support its work, the English formed the Royal Corps of Signals, which in conjunction with Admiralty monitoring, provided the messages for the codebreakers. (SIGINT, 98ff). The British Secret Service also took to putting its agents aboard merchant ships as Marconi wireless operators, when particular ports of call were of interest. (SPYCATCHER, 13).

Soviet subversion in England provided its first important work, with civil unrest widely feared. The London Times ran a story that wireless intercepts showed the Soviets funding subversive activity in August of 1920. Despite a treaty prohibiting domestic subversion, the Soviets kept it up, monitored in detail by the wireless intercept stations and decrypted at GCCS. (Ibid. 103). Various diplomatic initiatives attenuated the subversion for a while but also brought on the use of one-time encoding pads, very difficult to decrypt. (Ibid., 104, 119). In 1930 an intercept station detected a circuit between Moscow and a suburb of London. (Ibid, 120). It was not until the Spanish Civil War in 1936 that the British turned away from their focus on the Soviets. (It is, incidentally, my speculation that the circuitbetween Moscow and London, fully decrypted by GCCS, was left in place to monitor the success of Commintern subversion at Cambridge and Oxford, which led to the Philby affair many years later. See generally Genrikh Borovik, THE PHILBY FILES (Little, Brown, Boston, 1994, ISBN 0-316-19284-9)).

The Russians had dedicated themselves to the overthrow of the United Kingdom, and the English knew it, from intercepts and seized documents. (SPYCATCHER, 45). The English first, however, had to deal with the Nazis, who had even more immediate plans, as became clear in 1936, 1938 and 1939.

The English maintained since 1925 a "Y" committee to coordinate the work of intercepting radio signals. The Army had its chain of stations throughout the Empire, as did the Navy. The Post Office and the Air Ministry ran domestic stations. (SIGINT, 136). The listeners heard and logged the traffic, but understanding it was another matter, for the Nazis had implemented Enigma machine encoding. With the coming of real war, only the Poles had made any progress. The story of the decryption of the Enigma traffic is well known. (See, e.g., David Kahn, THE CODEBREAKERS (Macmillan, New York, 1967); SIGINT, chs. 3-6). That work may well have won the war in Europe; it certainly contributed far beyond its cost. What is not widely known is that enemy radio operators' errors gave away the codes far more than even the new electronic computers could break them. This was true and known to be true from the earliest days of encryption of wireless messages. Discipline is the key to security.

An American World War II Communications Security poster quotes the following First War example in order to heighten security awareness among U.S. operators:

"As early as 1914 the German station at Norddeich sent out by telegraph regular weather reports in mixed text. In these the cipher clerks had not taken the trouble to encipher the letters and numbers ordinarily used for indicating the direction and strength of the wind, etc.

"The station at Brugge, on the contrary, committed the inexcusable stupidity of transmitting the same telegram after having enciphered the said figures and letters. A comparison of the two telegrams gave an exceedingly valuable clue to the code used, and permitted ... a gradual reconstruction of great parts of it"

(Attributed to Yves Glyden, The Contribution of the Cryptographic Bureaus in the World War; From an illustration in Military Intelligence, at p. 67)

The U.S. Army and Navy continue monitoring in the 1920s and '30s, feeding traffic to the "Black Chamber," then the secret intelligence service, for cryptoanalysis, especially Japanese diplomatic communications.

Until 1929, American military intelligence fed radio intercepts to the "Black Chamber" of Major Herbert O. Yardley. Secretary of War Henry Stimson was scandalized at this spying and put an end to it rather abruptly. He said later: "Gentlemen do not read each other's mail." Yardley's success in decryption went for naught, and he went public in 1931 in the SaturdayEvening Post and a book. (SIGINT, p. 109ff).

Part of the American success had borne fruit at the 1921 Washington Peace Conference. Army Military Intelligence (MI-8) codebreakers decrypted the Japanese diplomatic code, for a considerable negotiating advantage (Military Intelligence, 45). The Army on a tactical level also engaged in monitoring and direction finding, as is illustrated by the 1940 set pictured nearby as it was operated in Hawaii.

The U.S. Navy also focused on the Japanese (as to some extent had the British as well). In 1927 (later Admiral) Ellis Zacharias set up a monitoring station at Shanghai, the first of a chain across the Pacific. (Nathan Miller, SPYING FOR AMERICA (Paragon, New York, 1989, ISBN 1-55778-186-9) at p. 216). Zacharias set up his receivers on the fourth floor of the American Consulate. (Palace, 34). By 1940 the chain of stations included the Aleutians Islands, the Philippines at Corregidor, Samoa, Guam and Hawaii (Ibid. 232) and Bainbridge Island, WA, Winter Harbor, ME, Jupiter, FL and Chelten on Oahu. (SIGINT, 205). The Navy also established lesser monitoring stations at Imperial beach, CA and Amagansett, L.I., NY (Palace, 158).

The Army, despite the closing of the Black Chamber, operated the Signal Intelligence Service shortly thereafter. The brilliant William Friedman ran the small group, which ultimately broke the Japanese Purple Code, providing the MAGIC decrypts that likely won the war in the Pacific. (Military Intelligence, 54; SIGINT, 204, 230ff). Friedman broke that code without any captured machines or codebooks (unlike the English success at the Enigma codes). Friedman's was an unequalled feat of mind that nearly cost him his. (SIGINT, 206).

The intercepts for the Army SIS came first from stations at Battery Cove, VA and Fort Monmouth, NJ. Fort SamHouston, TX and the Presidio at San Francisco came on line by 1938, along with the Canal Zone, Fort Shafter on Oahu and Fort McKinley in the Philippines. The next year, stations in New York harbor at Fort Hancock and Fort Hunt, VA joined the network. (SIGINT, 204). One irregular station appeared in San Francisco about 1931 at the private initiative of Col. Joseph Mauborgne of the Signal Corps, who listened at home (a busman's holiday) and recorded the traffic for Friedman. (Palace, 32).

The Army in the Philippines monitored the Tokyo and Berlin, and Tokyo and Moscow circuits, while the Presidio and Bainbridge Island listened to traffic on the Tokyo and Washington circuit. (SIGINT, 205). Panama focused on the Rome and Tokyo circuit. (Palace, 32). The Army SIS and the Navy equivalent organization "OP-20-G" shared Washington decryption duties in this period immediately before the Second World War.

The Americans and British traded intelligence information on the Japanese. The British in this period had four intercept stations in Australia, plus a Dutch station removed from Indonesia. The Americans provided the Purple Code keys and similar high level material including two Purple Machine Replicas as reconstructed by Friedman. (SIGINT, 208).

Counter-espionage work in the ether was the domain of the FBI, but the Coast Guard also made a claim to jurisdiction. (Palace, 36). Eventually, the Federal Communications Commission operated the Radio Intelligence Division (as fully detailed by its Chief, George Sterling in the 1962 Sparks Journal of the O.O.T.C. and 5 Antique Wireless Association Review (1990). Sterling was a leading radio authority and later an F.C.C. Commissioner)

It was the intercept station at Bainbridge that took the communication from Tokyo to the Japanese Ambassador thatinstructed him to break off negotiations at 1 PM Washington time, or just after dawn in Hawaii on December 7, 1941. (Palace, 38).

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