NMSAT :: Networked Music & SoundArt Timeline

1925 __ Wireless Vision achieved
Comment : “Such an announcement recently appeared in the London press! Strange and unbelievable as this concept of television might have seemed ten years ago, it now seems almost sure to materialize at some time not far distant. The idea of seeing what is taking place a thousand miles away would have been classed as the working of an unbalanced mind a decade or so ago, but now, after millions of us have heard, with perfect intonation, voices of speakers thousands of miles away, why should we be surprised at seeing things from the same distance? It is, as a matter of fact, as difficult a concept to picture radio carrying on voice communication- as it would be to have it carry picture messages to our eyes. In voice communication, sound has to be changed to electromagnetic waves to transmit the suitable energy impulses and then these have to be changed back to sound for the benefit of the listener. The eye requires electromagnetic waves for its activation, and this is exactly the form of energy used in radio communication. The transmission of pictures by radio has already been accomplished and many examples of these pictures have been printed in the daily papers. By most of the present methods it takes about twenty minutes to transmit a five-by-seven-inch picture. This process is really television. If the distant scene remains fixed for some minutes, it can evidently be sent by radio to the distant onlooker. Instead of gazing into the fabled crystal sphere, how- ever, he would look at some kind of a chart, ink marked or photographic, upon which the distant scene would be slowly reproduced. Now, if we imagine that such pictures could be reproduced in one tenth of a second instead of twenty minutes, wireless vision would be achieved. Thus the speed must be increased some thousands of times over its present value, but this is not at all unlikely. Many of us have seen the oscillograms by which the telephone engineer analyzes his sounds and the power engineer discovers what peculiarities exist in his transmission lines. Such pictures of electric current are reasonably accurate if the wave to be photographed does not reverse more rapidly than about one thousand times a second. To get pictures of frequencies higher than this has not seemed feasible in the past, yet recently it has been found possible to photograph electric currents which are reversing as rapidly as twenty million times a second. Here is an increase of speed of about ten thousand times, accomplished by an ingenious change in the method of photography employed. Instead of using light waves to affect the photographic plate, the electrons themselves, by the activities of which ordinary light waves are set up, are used to bombard the sensitized gelatine. This revolutionary step has increased the speed of oscillography thousands of times. By a similar application of the electron's activities to the problem of radio vision, the solution does not seem improbable.”. (“The March of Radio”, In “RADIO BROADCAST”, Vol. VII, no. 2, JUNE 1925, Garden City, N. Y., DOUBLEDAY, PAGE & COMPANY, 1925, pp. 205-206)
Urls : http://www.archive.org/stream/radiobroadcast07gardrich%23page/204/mode/2up (last visited ) http://www.archive.org/stream/radiobroadcast07gardrich/radiobroadcast07gardrich_djvu.txt (last visited )

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