EMPIRE BROADCASTING.

Otago Daily Times, Issue 20269, 30 November 1927, Page 16

EMPIRE BROADCASTING.

EXPERIMENTS PROCEEDING. SHORT-WAVE STATION AT CHELMSFORD, f (Fbom Oub Own Coreespondknt.) , LONDON, October 19. The efforts to establish a complete system of Empire broadcasting have made considerable progress (writes the Morning Post wireless correspondent), and if the proposed experiments of the British Broadcasting Corporation prove successful Empire broadcasting will soon become an accomplished fact. The Corporation is working in conjunction with the Marconi Company, and soon will have completed an experimental short-wave broadcast transmitting station at Chelmsford. This will make use of the two 480 ft masts which are situated there The transmitter is expected to be completed early next month, and when the corporation is ready to begin testing the engineers in the dominions and abroad will be advised. Arrangements have been made for the collection and analysis of reports of these experiments in various parts of tlie world. The call sign of the new station is SSW. It will use a power np to about 25 kilowatts, and will \york on a wavelength of between 20 and 30 metros, although probably the chief wave-length will be 24 metres. Should its performance be unexpectedly successful in the earlv stages, programmes may bo transmitted, but the public are not to lie officially informed at the beginning of the tests. Satisfactory progress is being marie with what has come to be. known as the ” spaced aerial ’* method o£ reception tor tvkd tvbVv, utynals. The chief diibeulty experienced in the reception of these transmissions is due to the phenomenon known as ‘‘ fading.'* It is believed ill at the reception of transmissions on the ultra short waves is made possible entirely through reflection. Unfortunately, considerable changes are taking place continually in the reflecting medium, with the result that the strength of the signals received at any given point is constantly varying. In the case of extended transmissions the variations take place so rapidly as com- , plotely to spoil the reception. Experiments indicate that the signals ‘ from two or more aerials spaced at con- i sidcrable distances apart may be com- j bined and treated in snob a way as to i produce a more constant and undistorted signal, which is therefore suitable for relaying by a local broadcast station.