THE WIRELESS WORLD

Otago Daily Times, Issue 23505, 20 May 1938, Page 2

THE WIRELESS WORLD

NEWS AND NOTES By Magna Vox Items of local interest are Invited by “ Magna Vox ” for publication In this column. It is necessary that such matter should reach this office by Tuesday of each week for insertion in the following Friday IYA, Auckland.—6so k.c., 461.2 metres, 2YA, Wellington.—s7o k.c., 526 metres. 2BL, Sydney.—74o k.c., 405 metres 2FC, Svdney,—6lo k.c., 476 metres. 3AR, Melbourne.—77o k.c., 390 metres SCL, Adelaide.—73o k.c., 411 metres, 4QG, Brisbane—Boo k.c., 311 metres. 3YA, Christchurch.—72o k.c., 416.4 metres. 4YA, Dunedin.—79o k.c., 379.5 metres 4YO, Dunedin.—ll4o k.c.. 261 metres ANSWERS TO CORRESPONDENTS ' Eliminator,” Morven Hills.—With your type of set, a small aerial often gives more satisfactory results than a big one, because the selectivity is greatly improved Also, there is probably a tendency in your set for the ,r.f. stage to oscillate wl’m the aerial is removed altogether, and when a short serial is used this value is much nearer to oscillation, point, and hence is more sensitive than when the first tuned circuit is fairly heavily damped >y using a long aerial. At the same time, you ha/e given no details of the outside aerial you are using, and it is therefore difficult to know whether the results you are getting are as good as they should be. F. O’D. Dunedin.— Try connecting the aerial to he top of the grid winding through a 0001 mfd. fixed condenser It this stops the set oscillating altogether, then replace it with a .00005 mfd. condenser of the pre-set type If, however, the set still oscillates too strongly, then the strongest possibility is that the grid leak is faulty. Try replacing it with one of 2 megohms. i ARTISTS TO ARRIVE Several artists who have' achieved fame overseas have been booked for radio tours of the Dominion by the National Broadcasting authorities. Heading the list is Alexander Kipnis the famous Russian bass,\ who will arrive in Wellington in June, following his season with the Australian Broadcasting Commission. Kipnis has been a principal of the Chicago Opera House for a number, of years and has also given numerous recitals in the United States. However, he has just concluded an altogether different tour of America and has revelled in the novelty of it. One of America’s most enterprising entrepreneurs had the happy inspiration of engaging five Wagnerian singers—tenor, soprano, basso, contralto, and baritone—in order to present programmes of Wagnerian music. Alexander Kipnis was the basso of this combination, which toured throughout the States as “The Wagnerian Festival Singers” and which was described by the New York Musical Courier as “the luminous quintet. June will also see the arrival of Danny Malone, who is being brought to Australia and New Zealand by Frank Neil, the well-known vaudeville entrepreneur. By arrangement witn Mr Neil broadcast concerts will be given by Danny Malone in each of me four centres. Other overseas singers due this year include Frederick Collier, bass-bantong; Clem Williams the popular Australian baritone, ami Gladys Moncrieff, the ever-popular musical comedy star. SHORT-WAVE TECHNICALITIES Some of the technical aspects of short-wave transmission and reception were explained by Sir Noel Ashbndge, chief engineer of the British Broadcasting Corporation, over the uo stations last Sunday evening. He dwelt particularly upon the impaired reception consequent upon displays ox the aurora borealis during the past few months and assured listeners that these harmful conditions were but a passing phase, and, as _ the aurora decreased in brilliance with the advent of the English summer reception would improve. On conclusion of nis discourse, which, in spite of its technical nature, was lucid and easily understandable by the layman, Sir Noel touched upon the effects of decisions reached at the international telecommunications conference held last month at Cairo. COAXIAL CABLES As a result of the demands of radio, the development of coaxial cables has proceeded apace. These cables consist of a flexible copper tube with a single wire drawn thi’ough it and held, at its centre by thin discs of hard rubber Using separate units for transmission in opposite directions such a cable will provide channels for 240 simultaneous telephone conversations. The latest coaxial cables are expected to be usable with a 2.000,000 cycle current, and if so, the single wire will provide for 480 telephone links, and also be able to take care of the very special requirements of the relay of television programmes, for which ordinary cables are quite useless. STEREOSCOPIC TELEVISING Coincident with announcements that colour television is now possible come announcements that Dr V. K, Zworykin, of • the Radio Corporation qi America, has developed a stereoscopic system to give the received image third dimensional depth. More important still, for picture-goers are quite content to view films lacking the above refinements,,is advice that new tubes have been perfected to give absolutely flickerless black and white pictures instead of the dark green and white images of a few months back. The new cathode ray tubes give a much larger moving picture, Tin by lOin almost double, that of the superseded pattern. These technical developments are impressive, but it cannot be ignored that little progress has been made in solving the problems of a financial structure to support the art and the provision of talent. So rapid is the progress on the technical side that receiver manufacture is virtually impossible, except for experimental purposes PROGRESS OF TELEVISION Although enormous sums, estimated at about £250,000 annually, have been expended by the British Broadcasting Corporation on television plant and programmes probably not more than 4000 “ view" receivers are in use in the greater London area. The high cost, around £IOO for a sound-picture receiver, and the small size, about Sin by sin, of the image, are the main reasons advanced for the poor patronage of this newest radio art. No doubt the reluctance to purchase receivers arises also from the fact that the transmissions are experimental and that,any advance on the broadcasting end will be accompanied by more or less radical improvements on the “ viewers." Experimental tests by the Baird Company in colour television add still another disturbing element. With such a position obtaining in London, It is not surprising that television on regular schedule has not been attempted elsewhere. THE “RADIO NURSE” A radio-electrical instrument popu larly called “ the radio nurse " is being introduced in America The device comprises two small units, a microphone called a ‘ guardian ear,” which will pick up the faintest whimper of a baby at the crib, and send it along to loud speaker units located in the kitchen or any other part of the home. Both devices arc plugged into the house lighting sockets and no other wire connections are necessary The chief uses of the “nurse’ are seen m the care of children and invalids. The “ear” may be installed in the nursery or sickroom, while the small loud speaker is located in any room where it is desired to hear all sounds in the other room. HERE AND THERE The 8.8. C. has, among many strange requests, recently been asked:—Where good feathers from different cockerels’ tails can be sold; the condition of the weather on August 29 1934 for purposes of a tapestry; whether ’ the world-famous pianist Padarwishie is dead; to reprimand, on religious grounds, a commentator on a football match who used the expression’ “ nell for leather.” , A new fleet ot ambulances in Sydney are equipped with 10-walt transmitters, which give them a; range of about 40 miles from the hospital, where a 200-watt transmitter adequately covers their service area.

Until the opening of the new stations a temporary 15-kw. transmitter has been constructed at Athens. This will be ready for operation in the spring Newfoundland, the oldest part of the British Commonwealth, is about to be given a new broadcasting system. At present two stations of the Dominion Broadcasting Co., and one of the Colonial Broadcasting System transmitting wholly-sponsored programmes arc the sum and substance of the radio field Another station, however owned and operated by the Wesley United Church, is on “ the air ” every Sunday with church services. All these stations operate on long-wave only, and do not therefore reach into every corner of the island throughout the year—reception in winter, of course being better than at any other time. During the past year more than oUOO gramophone records, which have been used for broadcast purposes, were presented to London hospitals, through the courtesy of the 8.8. C. and recordmanufacturing companies