RADIO IN OTAGO

Evening Star, Issue 23817, 22 February 1941, Page 4

RADIO IN OTAGO

WIRELESS TELEPHONY ARRIVES DR JACK'S UNIVERSITY STATION (Continued.) By the end of 1920,. wireless telegraphy had reached the height of its popularity. There were countless enthusiasts of the science in Australia and New Zealand, and a great deal of transmitting was going on within .Dunedin, and, of course, with a knowledge of the Morse code, hundreds of experimenters were “ listening _ in” to messages as far away as I 1 ranee and Holland. Various commercial concerns also transmitted from time to time in various parts of. the world, and there was generally a fair amount of shipping . to be picked up. But great things were in store, for wireless telephony, hitherto unkno*wn in Australasia, was shortly to make its appearance. Dr Jack, professor of physics at the Otago University, had been conducting experiments for a number of years, and on one occasion, had picked up the result of a world title boxing match from America two or three hours before the news was received by cable. EDISON VALVES USED. At the end of 1920, Dr Jack took a trip Home, and on his return in March, 1921, brought with him some Edison (ES4) valves, which were to be the means of providing the first wireless telephony broadcast in Australia. He also obtained from war stock some direct current generators which had been used on aeroplanes during the war. The exigencies of university teaching made progress in the early part of 1921 slow, but by the autumn of that year, successful transmission of speech and music had been accomplished. The reception of wireless telegraph messages by crystal and valve had already prepared the way for this new development, although at that date receivers were naturally much less efficient than they are to-day. _ The earliest experiments in transmissions were from one room to another within the University, where Dr Jack was ably assisted by Mr J. Sutherland. The excitement rose when it was found that’ the voices of the experimenters were being heard in different parts of Dunedin. Reports of good reception quickly followed from Mr Frank Bell, of Shag Valley, Mr (now Dr) M. Barnett, at Hampden, and Mr R. W. Orhell, at Christchurch. It was next of interest to know that good reception could be had on the other side of the Alps at Greymouth, for it was feared that the mountains would form too great a shield. Each day of transmisi sion saw progress in the distance at which signals could be heard. MUSICAL PROGRAMME BROADCAST, The plate voltage most frequently used was 800 volts, and the input was about 35 volts. It is a very remarks' able fact that at that time, with re- ; ceiVers at their then stage, it was possible to communicate with Christchurch by telephony, using only 30 volts in the plate circuit. A wave length of 450 metres was generally adopted, though others were used! from time to time. It is interesting to recall that at this early stage in broadcasting a programme of music was sent to H.M.A.S. Melbourne for a dance at Dunedin wharf, at which Lord and Lady Jellicoe were present. Later, messages and music were sent to a meeting of the Canter- - bury Philosophical Society, and on August 11, 1922,concert given by the University Musical Society in the Allen Hall was broadcast. Reports on this transmission from different parts of the country showed that this was clearly received. The station was visited by the manager of the Amalgamated Wireless Company of Australasia, the chief telegraph engineer, and the secretary of the New Zealand Post and Telegraph Department, as well as many experimenters among the fast-growing band of enthusiasts. STATION CLOSED DOWN. When broadcasting was undertaken by others it was felt that the province , of the University was not in providing ■ entertainment, but in undertaking re- . search in problems connected with wireless telegraphy and telephony. One of the students in the psysics department about this time was Dr Miles Barnett, now head of the meteorological • department at Wellington. lie it was who, in conjunction with Professor Appleton in Sir Ernest Rutherford’s laboratory at Cambridge University, was the first in the world to determine definite evidence of the Heavysido Layer, and to estimate its height. In the years following numerous experimenters achieved successful results in wireless telephony, but it is to Dr Jack that the honours of the pioneer-