RUGBY RADIO STATION

Evening Star, Issue 19272, 10 June 1926, Page 9

RUGBY RADIO STATION

MOST POWERFUL IK WORLD . NOTABLE NEW FEATURES The necessity _ for an efficient system of intercommunication among the widely scattered territories which constitute the British Empire became so. pressing that in 1920 a commission was appointed, with Lord Milner as chairman, to work out details of the Empire network ,of wireless stations that had been suggested some time previously. It was decided to begin,tho scheme by building a verv powerful station in England at a cost of £400,000; and accordingly, upon a site of 900 acres at Hilhnorton, near Rugby, there has been built what is probably the most powerful wireless station in the world.

This station was specially designed by the Wireless Telegraphy Commission and the wireless section of the engineering department of tho General Post Office. Toward the end of 1925 tho station had passed from the structural to tho range-testing stage, and early in 1926 was able to send out messages which could bo picked up not only in the remotest corners of tho British Empire and by ships at sea, but in every other country where there is in existence an efficient receiving station. The new station embraces features which register notable advances in_ the science of radio-telegraphy. It is a threefold station; it is alone among the world’s largest wireless stations in using the valve system of transmission; it has a novel installation for transatlantic telephony, more powerful than any in existence, and it is also a short-wave transmitting station. The outside appearance of this great achievement of modern engineering science is a series of twelve steel masts 820 ft high, carrying three miles of aerials, each supported by iifteen steel wire ropes arranged in groups of stays. Each long stay is I,oooft in length. At a distance the masts, stays, and aerials look like a delicate lattice-work. As tho site is 400 ft above sea level, th© actual altitude of the masts is over 1,200 ft. In each there is an electric lift (elevator) to hold three persons. There is also a steel ladder. Both means of travel are protected by safety devices. The twelve masts are a quarter of a mile apart, and support antomiffi of sausage type about 12ft in diameter. Those masts are constructed to withstand wind pressure of 140 miles per hour and a horizontal pull of ten tons at the top. Each one weighs about 200 tons, and has a ball-and-socket joint (to allow movement under external forces)j beneath which there are. porcelain insulators, specially designed and standing on granite blocks. Another notable feature in regard to the outside construction is that the earth wires are approximately 100 miles in length, A special plough was invented to dig trenches in which the < wires are embedded. Tbe Rugby site is on a level plateau, which enables uninterrupted transmission at the start. TUNING FORK CONTROL.

The valve house, apart from tho control and relay machinery, consists of a number of panels; inside these are the series of valves. In one of the centre panels is a steel tuning_ fork, maintained in continuous oscillation by a D.E.R. valve of tho typo with which wireless amateurs are familiar. This instrument was invented by Dr W. H. Ecclos and Mr Jordans as a war device for the timing of gunfire; at Rugby its purpose is to maintain vibrations at a regular speed of about 2.000 per second, and it serves as a “master oscillator,” keeping tho chosen wavelength to its exact dimensions. The engineers aro _of opinion that tho constant wave will help in reception through atmospherics, and listeners ought thereby to receive clearer messages. This opinion has already been borne out by reports that transmissions from the station are being received with extreme distinctness at very great distances. _ Tho nature of tho reception of the signals discharged at Rugby, when they reach a battleship off 'the Falkland Isles, n p«viria town in .Western Canada, a hill station in India, a sheep ranch in Australia, or any other part of the world, is thus regulated by, and dependent upon, tho diminutive tuning fork at tho originating station. Such perfection and sensitive exactness would not have been attained had not the Post Office Wireless Research Department invented supplementary apparatus, by means of which the osdilations started by tho tuning fork aro enriched in “ harmonics.” One harmonic is selected for amplification by means of tho valves in several stages, beginning with 50 watts in tho first stage and finishing in the case of Rugby with 500 or even 1,000 kilowatts. Tho current, released in waves of 18,740 meters, flashes signals instantaneously to tho uttermost parts of the globe. A speed of 100 words per minute can be attained; and by the tiro of both long and short wave lengths two messages can bo transmitted at a time.

OFFICIAL NEWS SERVICE. In addition to the ordinary commercial uses to which the station may bo put, it radiocasts the British Official Nows Service, hitherto transmitted from tile less powerful Loafiold Station. The service has in the past been widely published in the newspaper press of countries within the range of the Leafield station. Henceforward, it is at the disposal of newspapers throughout the world; anyone who so desires may erect a receiving sot (of which somo details will ho found below), and can listen three times every twenty-four hours to a service of news of British affairs.

These news messages arc compiled in tlio Foreign Office and are transmitted from the Contra! Telegraph Office via Rugby throe times daily—at 12 noon, 8 p.m., and midnight, Greenwich mean fame; the English language and the Morse alphabet aro used for these transmissions. By special arrangement the British Official News Rervicejs sent out at the low speed of about eighteen words per minute, in order to facilitate reception by stations which are not euipped to receive high-speed' transmission, and to insure accurate transcription by operators. The call letters of f lic new Rugby station are GBR, and the wave length on which the British Official Wireless Service is provisionally transmitted is 18,740 meters The wireless exports of the post office do not recommend super heterodyne sets for listening to the Rugby station. Apparatus suitable for the reception of the British official news service transmitted from Rugby may consist of the following components:— Two valves (tubes), high frequency with low decrement tuning circuits.

One independent heterodyne, One detector.

Two-valve note (audio) amplification with a single-tuned circuit, tuned to the note frequency.

the technical information given above should bo sufficient to enable any capable wireless engineer to design a suitable sot of apparatus for receiving messages from Rugby. A fuller specification may be obtained on application to the secretary, General Post Offioo, London, by those who are unable to obtain the Help of an engineer.