MARCONI'S NEW MARVEL.

Auckland Star, Volume LVIII, Issue 1, 3 January 1927, Page 14

MARCONI'S NEW MARVEL.

I WIRELESS BEAM SYSTEM. {TRANSMISSION AT SPEED OF FLASH. WHAT IT MEANS TO EMPIRE. | The Marconi Company recently reI ceived from the Engineer-in-chief of I the Post Office the official certificate | that the wireless stations constructed at I Bodmin and Bridgwater for conimuniI cation with Canada on the Marconi ! short-wave beam principle have passed | their official seven days' test, j A high-speed wireless telegraph ser- j vice between Great Britain and Canada through these stations is now operating. I AN itli the first Dominion beam service thus etsablished. 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 tlie Marcoiii beam stations for direct communication between the Mother Country and each of the Dominions, it possesses the most complete, up-to-date and efficient wireless service of any country in the world. 2500 Letters A Minute. It was in 1023, after several years of discussion, that the Government definitely decided to proceed with the erection of wireless stations to communicate with each of the Dominions, lhc 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 corresponding stations to form a complete Empire wireless service.

\\ hile negotiations were proceeding with the Marconi Company for the erection of high-power long-wave \alve 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 oe developed that would enable these Imperial services to be carried out much more efficiently and at ruu-li lower cost fhan was contemplated by the high-power long-wave wireless stations.

His plan was to use short wireless waves—-of 100 metres ur lees— 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 bv 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. lie 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 in favour of the new system that the whole technical policy of Imperial wireless communic&tion was revised and the Government entered into a contract with Marconi's Wireless Telegraph Company, Ltd., to build short-wave beam wiieless stations in Kngland to communicate with Canada, South Africa, Australia and India. The Government and wireless companies in each of these Dominions were equally imI pressed with the value of the beam [system, and contracted with the Marj coni Company to build corresponding stations to communicate with those being erected in England. Ihe building of the stations was started in April, 1925. They have been longer under construction than was at iirst anticipated, but this has been due to the fact that research work lias been carried no 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 their kind in the world. Advantages to Commerce. The institution of direct Marconi 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 taffic to be dealt with in the shortest possible time, will create new business that has not previousy been possible, and so bestow a great benelit on the commerce of Great Britain and Canada.

The beam transmitting station in Canada is situated at Urummondville, 30 miles east of Montreal, and the receiving station at Yamachiclie, 25 miles north of Drummondville. These stations are linked up by land line to the central oliice of the Canadian Marconi Company in Montreal, in the same way that the English stations are linked to the General Pott Office. Beam stations are also being erected in Canada for direct communication with Australia, and corresponding beam stations are being built at Melbourne.

The sites occupied by 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 feouth African stations are practically complete. Similar stations are being built at Tetney, near Grimsbv, and at \\ inthorpe, near Skegness, for communication with Australia and India ——the Grimsby stations being transmitting stations, and the Skegness stations receiving stations.

| Coiresponding stations are being built in the Dominions near Capetown. Melbourne, 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 scheme, but outside this scheme the Marconi Company is already engaged on a considerable development of commercial telegraph services on the beam principle. The company holds a license from the Post Onice to conduct wireless telegraph ser- \ ices with certain Continental countries and with all other foreign countries outside Europe. In addition to the wireless stations, it has been operating on these services for some years; it lias a ne"am station nearly completed-at Dorchester for communication with North and South America. A corresponding station is also in process of erection at Kio de Janeiro.

Advantages of Beam System. It is claimed that a beam wireless station lias the following distinct advantages over any other form of telegraph communications for point to point communication, over similar distances: —The capital expenditure involved is considerably less, it is more economical to run and maintain, and it ; is by far the most speedy method of communication yet devised. The speed of working the beam system is at present limited only by the meehanical limitations of the transmitting and recording instruments, and when suitable means of recording over landlines at higher speeds than at present obtainable have ben 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 has enabled the service to be carried on under conditons when signals obtained by utilising non-directional aerials were hardly appreciable. At the same time, the use of beam aerials has resulted in a very large degree of freedom from atmospheric disturbance. I