LIMITS OF RADIO

Evening Star, Issue 18280, 21 May 1923, Page 3

LIMITS OF RADIO

SECRECY IMPOSSIBLE. We are constantly reading of the enormous possibilities of radio, «iys a writer in the London 'Daily News,’ but they ■often over-estimated. A popular idea, foi ■instance,, is that the time will come when w© can step into a radiophone office in London, talk to someone in Australia, and sco them at the same time. That is a. physical possibility, but not so all the other conjectures which we hear made every day. Perhaps the one which appeals to the imaginative mind most often is that soon the ordinary laud-lino telephone will bo obsolete, and everyone will carry a pocket radiophone, by which they can call up whom they like. Wo read further:

“It Is common knowledge among wireless amateurs that the only way for two neighboring wireless stations by transmit at the same time without interference is by using a different wavelength.’ At present there are nearly a million telephones in use in England, and the number is steadily growing. Tf pocket radiophones were to be _ substituted it would mean that, to avoid interference, nearly a million different wave-lengths would have to be allotted. It is only possible to adjust and gauge a wavelength, within ten or twentv metres. “ For a, message to travel any distance it would Ixi necessary to carry current, and a large dynamo or accumulator can hardly be called 1 portable.’ “ Further, secrecy would be impossible. At present all radio messages travel in every direction, and even when ‘directional’ wireless is introduced absolute secrecy is an impossibility. ■‘Another popular idea is that when radio is fully developed criminal will all be run to earth by radio. But will they. The finger-print system of detection was regarded ns infallible until it was found possible to forge finger-prints. Radio in, tracking criminals will do well enough—imt.il the criminals realise that _ ‘ spoof messages could easily' be transmitted by them to put the police off the track ; and the old trouble of lack of secrecy would bo, a decided disadvantage to the police officials. “ That radio broadcasting will replace the newspaper is another common view, I am convinced that this will not be so. The news bulletins at present broadcast are novel, but the material given out does not appeal to all; and once the news is given there is no means of referring back unless notes are taken, and that is laborious compared with just looking through the news sheet. “ (Ireat excitement prevailed recently when wireless conversation was carried out across the Atlantic; but, as Marconi pointed out, too much must not be made of this achievement. The feat was carried out under exceptionally favorable conditions. It was dark, anti radio travels best in the dark. It was also winter, when the annoying ‘atmospherics’ (crackling sounds in'the instrnments_ caused by Nature’s electricity, and which mar speech considerably) were entirely absent. “ The great drawback in radio, and on© which seems impossible to overcome, is that the ether through which the wireless travels will hold only a certain amount of ‘ business ’ and no more. If more than its limit is transmitted interference is inevitable.”