What Has 1931 Meant to Radio Development?

Radio Record, Volume V, Issue 25, 31 December 1931, Page 1

What Has 1931 Meant to Radio Development?

A Critical Analysis of the Year’s Achievements

by

Observer

EVELOPMENTS in radio cannot be portioned into years; they take place in stages, usually separated by long periods and clearly defined so that it is very difficult sometimes to say what has happened in one calendar year. . Up to the present we may divide radio into several clearly defined stages. First, the experimental stage. This was followed by elementary broadcasting which stage the valve ushered in. The gradual improvement of the valve, not only as a receiver but as a transmitter, was responsible for bringing people to realise that radio provided an unequal means of entertainment. Yet radio was not universally popular. It wanted some major improvement in order that it should be enjoyed by all. It was too complicated and too uncertain. Came the electric set, and this provided means to make broadcasting popular. Almost overnight it grew from an expensive hobby to serious competitor of all forms of entertainment. Radio has now passed that.stage and is looked upon as an everyday affair, simple, effcient and almost indispensable. What our next stage will -be it is not very hard to forsee-it will be television. It did not come last year, and it is doubtful if it will come this year, but when it does radio wil; undergo a sweeping change and more than ever it will become an essential of every home. Last year, then, is just one of the years which are tucked away in the period which marks the entry of radio into the home. As in the year preceding our radio sets were simplified and slightly improved. Not much improvement can take place in a modern set-it is simple and efficient. .

Of course there have been certain changes during the year. As we predicted last year the set has generally become very much smaller, and now pr giftbly nine-tenths of the sets are the mantel or compact type, better known as midgets. When the first midgets came they aimed at bringing radio down to a price and incidentally to a size. This they did with remarkable success with the results that the midgets acquired a very bad name. But it was the type of set which appealed. Small, neat and portable, it offered many ad,vatitages over the Jarger and more .for less cumbersome piece of furniture which stood back in one corner. After the first. midget rush ended, engineers turned toward the problem of compact radio seriously. The result has been that this year has seer) many splendid models come out. The most reliable manufac-

turers in the world have turned their attention toward them and turned out machines that have brought credit to their name. In the older sets there was undoubtedly a great deal of waste space. It was thought at first that space was needed to separate the components so that better results could be obtained, but even allowing for components to be spread out there was a great deal of space wasted. Now this has been eliminated. As we would expect, the idea of minimising space has been overdone. There are sets that are undoubtedly jammed into far too small a space and, what is more, many of them are far too light. There is a point beyond which, at the present time, it is impossible to go. There is a difference between economising and skimping and many of these smaller machines have unquestionably been skimped with detritnental effects. Many, too, have been made to a price and they have caused dissatisfaction with radio generally. ie order to economise on the modern set it is essential that the number of -components be reduced, but instead the super-heterodyne circuit, which required more valves than the ordinary t.r.f. circuit, was developed. It was because of the development of this circuit that American engineers turned their attention toward the pentode, a valve which had been developed in Continental laboratories some five years earlier and since used in many Continental and English sets. This valve, which has a remarkable amplification, does away with a complete stage-a valve and coupling device, which may possibly be a bulky transformer. The development of the pentode has saved radio a great

deal of space. In order to make the set capable of giving more vol-. ume and yet maintaining quality, American engineers developed the multi-mu valve-really a combination of two types, the power valve and the high amplification screen erid valve. The perfection of these twa valves forecasts rather an interesting development, that is the combination of several valves in oné piece of apparatus. In order to amplify, certain coupling devices must be employed and, in the earlier days, three in one valves were developed with these coupling devices within the glass. It is likely that although the actual system used will not be further developed, the idea of combining the function of several valves into one will be pursued. Like everything else they are becoming very complicated in (Continued on page 2.)

Radio in 1931 (Continued from page 1.)

structure.and in function. Possibly. they will become dearer but they will be fewer and will last .longer. A jwalve with a replaceable filament has already -appeared, but it seems not to have been commercialised-probably for obvious reasons. A short time ago we heard a great @eal about. the Stenode Radiostat-a superheterodyne type of circuit which used a quartz crystal as a stabiliser. This type of set gave a separation of stations hitherto believed impossible. Whe year 1931 saw it evolve.from the Jaboratory: and become a commercial product. Kit sets are now being sold in the United States and quite a number of the sets appear to be in operation. One of the chief present objec- | tions is its costliness but, as in other 'gevelopments, this is only a prelude, and it is not unlikely that we shall see the Stenode. circuit embodied in the commercial receiver of the future. Concerning the superheterodyne cir‘euit which seems to have captured the ‘Smagination of both the American and |New Zealaud public, serious criticism ean be. directed. Undoubtedly the circuit is sensitive and more selective: than the normal, but being more sensitive it amplifies noise to a far greater degree than is sometimes pleasant. Furthermo‘e, it has the unhappy knack of picking much of the parasitic noise from the power lines and giving this to us through our loudspeakers. This has made many enemies for radio and incidentally for the electric set. Already some of the newer models have reverted to the older circuit with slight modifications, The Progress of Television. WHiLe it cannot be said that television has made marvellous ptrides, yet it has made progress, and one of the most outstanding events of the year was the announcement by the B.B.C. that transmissions will take place from their studios and actually be included in the broadcast programme. It is proposed to transmit such well-known and popular artists as Jack Payne and his celebrated B.B.C. dance orchestra. Further, the B.B.C. is investigating the possibilities of conveying the television signals by land line to their regional station at Slaithwaite. It is interesting to note that Sir John Reith, the director of the B.B.C., recently visited America and "upon returning gave consideration to the Baird, a British system. Speaking on television recently, Mr. K. T. Fisk, managing director of Amal-

gamated Wireless, and one of the outstanding figures in radio, made a statement that: television to-day is an accomplished fact but it had limitations, those limitations being the size and vividness of the picture, which is cnly two or three inches square, Mr. Fisk said that he believed that the success We are aiming: at‘is just around the corner, and, that any day we may

discover some new steps which will ‘take us right to our objective. "We shall look forward to witnessing in our own homes the Melbourne Cup 4s it is run. Going further, we may expect te sit at home in any part of the world and witness His Majesty the King opening the British Parliament, or see the President of the United States talking in the White House on an important world subject." And so it must be admitted that the year 1932 may possibly, witness the ushering in of‘a new stage-a new era in the evolution of radio, and that era is television. The Miero-ray. ¥ great importance was the successful transmission of the micro-ray. ‘The system, employing ultra shortwaves of approximately 18 centimetre (7 inches), was used for the first time on March 31 to provide a high quality two-way radio telephone circuit, the power used being only half a wattjust sufficient to light a flashlamp bulb. Perfectly normal conversation was ex--changed between Dover and Calais. For maintaining secrecy of communication, the micro-ray offers infinite possibilities and it has valuable application in the direction of aircraft landing (uring fog. Thomas Edison. RESUMBE of the year 1931 would not be completed without recording a great loss to radio-I refer to the death of Thomas Alya Edison, America’s greatest inventor, Edison, it will he remembered, was the pioneer of the electric light and literally a hundred and one inventions in the electrical world. It was Edison who developed the gramophone which has now become the close associate of radio, an electric dynamo, motion pictures and a long list of inventions which have meant much to modern civilisation. The world is much poorer by his death.