WIRELESS TELEGRAPHY

In the years before the outbreak of World War I, different schemes, as well as Alexanderson’s alternator, were examined in order to produce continuous waves. The Marconi company, among others, had earlier developed spark transmitters. An improvement of the Marconi system was the rotating spark gap, producing nearly continuous waves. This new system was first used at Marconi’s large station in Ireland and later also at Poldhu in England, Cape Cod on the USA’s east coast and Glace Bay in Canada. The first regular wireless telegraph traffic service over the Atlantic was opened between Clifton and Glace Bay on October 17, 1907.

In Germany, Slaby-Arco and Braun-Siemens systems passed into AEG’s (Allgemeine Elektrizitäts Gesellschaft) possession. A patent war broke out between AEG and the company Siemens & Halske, which with help from Professor Ferdinand Braun had prepared a competing system. A settlement was made in the year 1903 and the unified system took on the name Telefunken.

In 1909, 675 Telefunken stations had been delivered on all continents, except Australia, comprising 200 stations on land, 400 ship stations and 75 military field stations. In the USA the system was represented by the Telefunken Wireless Telegraph Company of the United States with registered offices in New York. An entirely new method of producing waves (Tönende Funken) was prepared for Telefunken by Professor Max Wien at the Technical University in Danzig. The Swedish engineer R.H. Rendahl, then manager of the Telefunken laboratory, contributed actively to the development of this system, which was on the market in 1909.

The Danish engineer Valdemar Poulsen had introduced his arc transmitter for continuous waves to the American market. The Poulsen Wireless Corporation was formed as a holding company, while The Federal Telegraph Company was responsible for technology and plant operation.

Large stations in Arlington (Virginia), Los Angeles and San Francisco were built, and one station of 30 kW output was built in May 1912 on Honolulu. The navy tried out the new transmitters and could certify that one could not only telegraph from Arlington to San Francisco but also directly from Arlington to Honolulu. When the USA entered World War I, the American Navy aquired all “Federal” stations.

A large station of 1000 kW was built for the great “Lafayette station” in France in order to secure communication between USA and Europe.
However it did not play any role during the war, as it was only put in operation in the year 1920.

The problem of making a generator produce continuous waves at high frequencies and high power had in 1912 found a solution in an invention by Rudolph Goldschmidt, Professor in Electrical Engineering at the Technical University in Darmstadt, Germany. He had earlier been Chief Electrical Engineer at the English Westinghouse Company. The method was based on connections of appropriate tuned circuits to rotor and stator windings in an asynchronous motor design to create an alternating current generator. The AC energy is induced from rotor to stator and vice versa a certain number of times. In this way, the AC frequency is increased at each induction in accordance with the number series 1,2,3,4…

In the year 1913, a station with Goldschmidt’s system, of 200 kW power, was built in the small town of Eilvese, 30 km northwest of Hannover in Germany and at the same time a station of the same size was built in Tuckerton, N.J., USA. Between these stations, a distance of 6500 km, the Goldschmidt system for radiotelegraphy was successfully tested.

WORLD DOMINION OVER TELEGRAPHY
In 1915 when Guglielmo Marconi visited General Electric, England had built a world dominating cable network for telegraphy and through Marconi’s way of training personnel, both for land based stations and ship stations, the British had strengthened their world domination in long-distance wireless communication. Under the chief company, the Marconi Wireless Telegraph and Signal Company in London, there were at this time different Marconi subsidiaries in the following countries: USA, Canada, Argentina, France, Belgium and Spain. In addition The Marconi International Marine Communication Company was registered in London. The common objective was to spread and develop the Marconi system all over the world.

Since the alternator generates continuous electromagnetic waves, it is suited for both wireless telegraphy and telephony. To the experiments with the alternator in the year 1916 were added regular broadcasts from the laboratory in Schenectady. The transmissions lasted for one hour and many radio amateurs all over USA listened, wrote letters and described the reception.
By that time an operational electronic high frequency amplifier was available. The purpose of the dinnertime transmissions was to communicate by wireless, but there was no thought of introducing regular broadcasting. It was of scientific interest and not for amusement of the amateurs listening. General Electric was only concerned with creating a reliable system for wireless telephony, in particular for transatlantic traffic.

At this time, all commercial interest was aimed at wireless telegraphy and Marconi’s interest in the alternator was primarily for its use in telegraphy. Alexanderson’s design met Marconi’s requirements and also simultaneously met the dreams of Fessenden of transferring wireless messages over long distances by telephone.

EXCLUSIVE RIGHTS TO USE THE ALTERNATOR
It was clear that Marconi, after having met Alexanderson in Schenectady and having studied the alternator more closely, was entirely certain of the possibilities of solving the so far unresolved problem of achieving a reliable system for wireless communication over the Atlantic Ocean.

The evidence was not just the order of an alternator for the Marconi station in New Brunswick. Marconi also negotiated with the Chief Counsel of GE, Owen D. Young, later the Chairman of the Board, for an agreement between the Marconi company and GE. The agreement would give GE the exclusive right to produce alternators, while the Marconi companies would have the exclusive right to make use of them. In order to implement the agreement it was required that the Marconi companies would order a large number of alternators, for millions of dollars. The negotiations were interrupted because of the war, but later resumed, a subject to which we will return later.

When the U.S. Navy took over the station in New Brunswick in April, 1917, Alexanderson’s 50 kW alternator was immediately pressed into use for transatlantic traffic. Comparing tests with other transmission systems showed that signals from the alternator were superior, and reached Europe with reliability. A contributing reason was the greatly increased radiated power that Alexanderson gained with his “multiple tuned antenna” replacing the earlier antenna installed by the Marconi company. With the new antenna system, the radiated power was six times higher.

In the meantime, Alexanderson worked on a 200 kW alternator which was installed in the summer of 1918. The small transmitter was replaced by the larger one, and at the same time the operating wavelength was changed. Both telegraph and telephone traffic reached friend and enemy alike in Europe and the New Brunswick station’s press messages were transferred to the media in the war-stricken countries.