World
of Wireless

RADIO TOPICS.

THE TRANSATLANTIC BROADCAST TESTS.

It will be remembered that last year The Wireless World an Radio Review, in conjunction with Radio Broadcast of America, organised a series of experimental tests of broadcasting between the United States and this country. The British Broadcasting Company kindlyco-operated and conducted transmissions to America, whilst on the other side Mr. Lynch, editor of Radio Broadcast, had the support of the majority of the American broadcasting organisations in arranging for transmissions to England. This year, as we have previosly announced in The Wireless World and Radio Review, a further series of tests wil be carried out from November 24^th to November 30^th inclusive, and altrough no detailed announcements have appeared recently in the columns of this Journal, the arrangements for the tests have been going forward steadily, and we are now in a position to give further particulars. The British Broadcasting Company has again this year kindly undertaken to participate and the arrangements have been extended further by inviting broadcasting stations on the Continent to come in and join in the transmissions to America. As a consequence stations in almost every country in Europe will participate. The interest which has been aroused in America and Canada over these transmissions in enormous, and so complete has been the response to the invitation made by Radio Broadcast that American broadcasting stations should co-operate that it has been possible to carry out arrangements whereby practically all American stations, have undertaken to keep silence during the ours when the European stations are transmitting. Of course, it will be realised that the interest in America in these tests is likely to be greater than on our side for the reason that the ordinary hours of evening programmesof Eurpean broadcasting stations correspond to hours of daylight in America and the conditions are therefore so unfavourable to reception of the European stations that we understand it has not been possible for Americans to listen in at all to our programmes. By arranging for European transmisssions to take place in the early hours of the morning we have got over this disadvantage and the hour of silence when America will listen for Europe will be during or immediatly following their usual broadcast programme hours. In order to give Europe a special opportunity for listening to America, endeavour has been made to ensure as much quiet on this side as possible whilst the American and Canadian stations are conducting transmissions.These transmissions will be specially intended for European listeners and wherever possilble increased power will be used by the transmitters. In addition to special musical programmes, various speeches will be made. The American transmittions will take place from 3 a.m. to 4 a.m. G.M.T. each morning from November 24^th to 30^th inclusive. European transmittions will follow immediatly from 4 a.m. to 5 a.m. and these will be by the stations of the British Broadcasting Company, including 5XX on the mornings of the 25^th, 27^th and 30^th November, whilst Continental Stations will transmit as a unit from 4 to 5 a.m. G.M.T. on the mornings of the 24^th, 26^th, 28^th and 29^th. All stations participating in the transmissions will give indications of their identity at frequent intervals in their transmissions, in order that the American listners may quite sure what stations they are receiving. The four parisian broadcasting stations will all participate in the tests, and among the other Continental stations also engaged will be those at Madrid, Brussels and Rome, and the German stations at Berlin (Vox Haus), Hamburg, and Koenigswusterhausen. The organisation of the Canadian broadcasting stations in the international tests is in the hands of Mr. J.N. Cartier, who is the manager of the station CKAC owned by La Presse, Montreal. If you could take a look in the studio of this station, and it will be seen to prossess several novel features, and attention might be drawn to the novel method of controlling the extent of damping. The draping over the ceiling is removable, giving control of sound absorption and echo. In America the tests provide unique opportunities for finding the extent of the renge of receivers. Captain Eckersley, when he broadcast from 2LO the other evening an account of his visit to America, told us that the American listner attaches more importance to the selectivity and rangecovering properties of his receiver than to its efficiency as a reproducer of good quality music and speech, so that the American will have special interest in these tests. Captain Eckersley has taken a keen interest in these arrangements and on his visit to America recently he met Mr. Arthur Lynch editor of Radio Broadcast, and the opportunity of discessing the details for the tests. Since last year 's tests a marked improvement hasbeen made in the design of American receiving equipment. For instance, it was not until quite recently that the use of neutrodyned receivers came into general use, and the present extensive adoption of this type of set, with efficient amplification at high frequency, is likely to give rise to good reception of the European signals an a considerable scale. The Supersonic heterodyne arrangement has also developed in the hands of the American public, and outfits of this class are in fairly general use. The inerest in America has not been confined to the United States alone, for Canada, Cuba and Porto Rico and other countries are also taking an equal interest in the arrangements.