MARCONI’S NEW MARVEL

Taranaki Daily News, 8 January 1927, Page 2

MARCONI’S NEW MARVEL

WIRELESS BEAM SYSTEM TRANSMISSION AT HIGH sFeED. WE.'.“ I:’ .’.l ILANS TO EMPIRE. The Alareoni Company recently received from the Engineer-in-Chief of the Post Office the official certificate that the wireless stations constructed at Bodmin and Bridgwater for communication with Canada on the Alareoni short-wave beam principle have passed their official seven days’ test. A high-speed wireless telegraph service between Great Britain and Canada through these stations is now operating. With the first Dominion beam service thus established, Great Britain’s world leadership in wireless communication is maintained. As the home of Senator Marconi's first long distance wireless experiments Great Britain was the pioneer country in commercial wireless telegraphy. Now, with the modern high-pOwer valve transmitting station at Rugby for all-round communication, and the Marconi beam stations for direct communication between the Alother Country and each of the Dominions, it possesses the most complete, up-to-date and efficient wireless service of any country in the world. 2508 LETTERS A MINUTE. It was in 1923, after several years cf discussion, that the Government definitely decided to proceed with the erection of wireless stations to communicate with each of the Dominions. The Dominions had been pressing for such a service for some years, and when the British Government’s decision was taken they immediately put arrangements in hand for the erection of < /responding stations to form a con 'te Empire wireless serviced V<hile negotiations were proceeding with the Marconi Company for the erection of high-power, long-wave valve transmitting stations to carry out those services, Senator Marconi became convinced, as the result of his experiments, that a new system of wireless telegraphy could be developed that would enable these Imperial services to be carried Out much more efficiently and at much lower cost than was contemplated by the high-power, long-wave wireless stations.

His plan was to use short wireless waves—of 100 metres or less—which, contrary to the generally accepted theory at that time, he had proved to be reliable for communicating over great distances; also to increase the strength of signals and the speed and efficiency of working by employing reflectors to concentrate into a narrow beam the wireless energy at the transmitting station, and to reflect a greater amount of energy on to the receiving aerial at the receiving station. As Senator Marconi has said, a considerable amount of courage was. necessary to propose such a revolutionary change. He had no uncertainty, however, neither had the company of which he is the chairman; and the proposal was put before the Government. So convincing were the arguments iii favour of the new system that the whole technical policy of Imperial wireless communication was revised and the Government entered into a contract with Marconi’s Wireless Telegraph Company, Ltd., to build short-wave beam wireless stations in England to communicate with Canada, South Africa, Australia and India. The Government and wireless companies in each of these Dominions were equally impressed with the value of the beam system, and contracted with the Marconi Company to build corresponding stations to communicate with those being erected in England. The building of the stations was started in April, 1925. They have been longer under construction than was at first anticipated, but this has been due to the fact that research work has been carried on simultaneously with constructional work, and many valuable improvements on the original designs have been made as the work progressed. Power valves have had specially to be designed to deal with the extra high frequencies of shortwave working, and the Marconi oilcooled valves at the transmitting station are claimed to be the most efficient of tlteir kind iu the world. ADVANTAGES TO COMMERCE. The institution of direct Alareoni wireless telegraph services between London and Paris and other Continental centres has shown that new telegraph traffic is created by the provision of new and rapid means of communication. It can therefore be anticipated that the establishment of the beam services, which can be worked at a speed which will enable large volumes of traffic to be dealt with in the shortest possible time, will create new business that has not previously been possible, and so bestow a great benefit on the commerce of Great Britain and Canada. The beam transmitting station in Canada is situated at Druramondville, 30 miles east of Montreal, and the receiving station at Yamachiche, 25 miles north of Drummondville. These stations are linked up by land line to the central office of the Canadian Marconi Company in Montreal; in the same way that the English stations are linked to the General Post Office. Beam stations are also being erected in Canada for direct communication with Australia, and corresponding beam stations are being built at Afclbourne. The sites occupied Ixy the beam stations •at Bodmin and Bridgewater for communication with Canada are also utilised for the stations to be used for

communication with South Africa. These South African stations arc practically complete. Similar stations are being built at Tetney, near Grimsby, and at Winthorpe, near Skegness, for communication with Australia and India —the Grimsby stations being transmitting stations, and the Skegness, stations receiving stations.

Corresponding stations are being built the Dominions near Capetown, Mel-

bourne . and Bombay. All these stations are in an advanced state of construction.

and are expected to be opened within the next few months. This will complete the present Imperial sei me, but outside this scheme the Marconi Com-

pany is already engaged on a considerable development of commercial telegraph services on the beam principle. The company holds a license from the Post Office to conduct wireless telegraph services with certain Continental countries and with all other foreign coun ■ tries outside Europe. In addition to the wireless stations,, it has been operating on these,services, for some years; it has a )>eam station nearly conqileted at. Don for communication’ with North

and South America. A corresponding station is also in process of erection at Rio de Janeiro. ADVANTAGES OF BEAM SYSTEM. It is claimed that a beam wireless station has the following distinct advantages over any other form of telegraph communications for point to point communication, ovei- similar distances: —the capital expenditure involved is considerably less, ’ is more economical to run and maintain, and it is by far the most speedy method of communication yet devised. Tlie speed of working the beam system is at present limited only by the mechanical limitations of the transmitting and recording instruments, and when suitable means of recording over landlines at higher speeds than at present obtainable have been developed, it will be possible to increase correspondingly the over-all speed of signalling. The results of tests between England and Canada have shown that the use of beam aerials at both transmitting and receiving stations has resulted in a strength of signal some 100 times that obtainable with non-directional transmitting and receiving aerials at each end, and. utilising the same power, and it 1 • enabled the service to be earned on i... .t v, conditions when signals obtained by utilising non-directional aerials were hardly appreciable. _ At the same time, the use ot beam aerials has resulted in a very large degree of freedom from atmospheric disturbance.