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TECHNICAL. Early in the year a self-contained emergency transmitter manufactured by Amalgamated Wireless (Australasia), Ltd., was installed at Wellington, and under the call-sign 2YC is providing an alternative service for four hours daily. This transmitter is of modern design, has a power of 200 watts aerial energy, and can be operated independently of the city power-supply. The opening of the new 3YA transmitter situated at Gebbie's Pass, near Christchurch, was the outstanding event of the year in broadcasting. The coverage given by the station has exceeded expectations. Installed primarily to give reliable service to the Canterbury District, the transmitter is, in addition, affording an alternative service of good quality over a much wider field. The performance of the station conforms in every respect to modern practice, having a flat frequency response over a band of frequencies extending from 30 cycles to 10,000 cycles per second, and a modulation capability of 100 per cent. These factors account for the faithfulness of reproduction which has been the subject of favourable comment by many listeners, musically inclined. Although some licensees using crystal reception in Christchurch had difficulty at first in receiving the new station, it has been clearly demonstrated that such sets, with minor alterations, are capable of giving high-grade reception. One of the main reasons for placing modern high-power transmitters out of city areas is to avoid " wiping out " reception of outside stations. Had the new transmitter been erected in the city, many listeners would have found it impossible to receive other stations without an undesirable background of the transmissions from the new 3YA. It is interesting to note that measurements taken with a modern field-strength measuring set prove that the strength of signals from the new station exceeds to a remarkable degree that given by the old 3YA station. For example, at Timaru the strength is now sixteen times, at Geraldine thirteen times, and at Ashburton eight times greater than formerly. During the year great improvement was effected in the 2YA transmitter and associated equipment, the frequency response and depth of modulation having both been considerably extended. The Board's engineering staff spent a good deal of time in determining the best location for a new transmitter to serve the Auckland area. Full use was made of the Board's portable testing transmitter and the field-strength measuring equipment, and having regard to the areas and population to be served, there is no doubt that the site selected near Henderson could not be improved upon. Amalgamated Wireless (Australasia), Ltd., were the successful tenderers for this transmitter, which will have a power of 10 kilowatts aerial energy, and, like the new 3YA apparatus, will be of modern design. The aerial system to be used is that known as the British Broadcasting Corporation's half-wave umbrella type, which requires only one mast approximately 500 ft. high. Full investigation leaves no doubt that this type of aerial structure affords maximum ground-wave radiation, this being the first consideration where a non-fading service is to be given over an extended area. The new transmitter will be brought into use this year. Work has commenced on the new studio and office premises in Shortland Street, Auckland, and these are to be completed in approximately eight months. Modern practice has been followed in designing the studios, particular attention having been devoted to acoustical requirements and to sound insulation, both external and internal. All the materials being used have been chosen in order to get the optimum reverberation period, a necessary condition for faithful musical reproduction. In order to prevent the leakage of street and other noises, no external windows will be provided in any of the. studios, and consequently artificial ventilation is essential. Special apparatus is being installed for this purpose, the contractors being A. and T. Burt, Ltd. The successful tenderers for the building were C. W. Ravenhall, Ltd., of Auckland. The operation in Auckland, Wellington, and Christchurch of three alternative or subsidiary stations was inaugurated smoothly. These are being worked in conjunction with the main stations, and very little extra expense in the way of staff costs has been incurred. During the year all the main stations were equipped with modern microphones of the velocity or ribbon type, and the result has been a marked improvement in musical reproduction. Until quite recently, the development of the microphone had lagged behind the studio and transmitter equipment, but this has been remedied by the introduction of the velocity type of microphone. The studio and subsidiary equipment, such as relay amplifiers, has received attention at each station, with a view to bringing the overall transmission up to the highest possible point of efficiency. The old 3YA transmitter now being operated as an alternative station at Christchurch under the call-sign 3YL, was overhauled and modernized before being reopened. The transmitter formerly used at Station 2ZW, Wellington, is being overhauled, and will be brought into use as soon as possible as an alternative to 4YA, Dunedin, At an early date the Board's engineers will undertake an investigation with a view to determining the most suitable location for a new transmitter to serve the Otago area. The portable test transmitter and field-strength measuring-equipment will be used for this purpose, and no time will be lost in calling for tenders when the appropriate site has been selected. On the Ist December changes in the wave-lengths of the Board's transmitters took effect and aroused considerable interest and some criticism. These changes were the outcome of conferences between the Board's engineers, the Post and Telegraph Department, and the Commonwealth authorities, and were made for the purpose of securing the best condition of reception for a majority of listeners in this country. The full beneficial effect of the changes will not be apparent until the completion of the Board's coverage programme, but already in many areas there is definite evidence of

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