GROWING WIRELESS

Evening Post, Volume CV, Issue 25, 30 January 1923, Page 6

GROWING WIRELESS

GREAT FRENCH INDUSTRY

EIGHT YEARS' PROG-BESS.

One of the matters which France has given, considerable attention is that of developing wireless, and in this industry, for it is now considered as a national industry in France, the country has made progress that may be claimed* to be ahead of that of any other country. Certain phases of the industry were dealt with at a public meeting,, which was largely attended, at thej King' 6 Theatre yesterday afternoon, by Lieut.-Com-mander Tranier, one of the officers of the French cruiser Jules Michelet.

He said the war had retarded progress \ in some directions, but stimulated it' in many otheis. The war-time requirements of the Allies as well as oi the rrenca armies absorbed the output of the ne'.v industry; Since then day after day ..iad seen further improvements toward; die perfection of the apDaraWs. -Geneiai Gerrie had brought together ali the .scientists and engineers and directed all the wireless work and research. Ali the problems concerning i eceivin^ and Uan^ nutting had been solved or were near inir solution.

The machines that gave the greatest power at the aerials were built in fiance and the, largest and most powerful station in .the world was the French om at Sainte Assise. Wireless in" France was now controlled by very large firms, strong enough to give all the, backing necessary to what mieht be deemed a great national industry. . The number of installations on aeroplanes i» France exceeded 15,000, and 600 stations were fitted on capital war^ ships, cruisp.rs. and destroyers, 200 or; scouts, submarines and smaller vessels and there were in use .12,000 vacuum tube amplifiers, receiving sets by the thousand, and many other pieces of ap paratus. The Societe Francaise Badio electrique had built high powered transoceanic and trans-continental stations, and some of the biggest stations in theworld had been fitted with apparatus from France. Lieut. Tranier claimed that, the superiority of the French-made machines was an acknowledged fact The Japanese Navy had admitted it in ordering several sets, some of 250 kilowatts. The fitting of receiving apparatus had .been most carefully studied both for automatic machines used for commercial heavy traffic over long dfe-" tances and for naval and private stations. Selective.anti-paraßitic apparatus, the latest in design, enable messages to be received and printed automatically, notwithstanding atmospheric disturbances. Following on these'improvements, he continued, the technique of wireless as a whole had become an important branch of electrical science, and had enabled radio to become one of the most important economic tools vital to the hfe of countries. Only a few years agbi any important wireless plant might be likened to a complicated, noisy, fragile, and clumsy workshop, calling for a great number of hands all highly specialised? To-day these plants compared with- a modern factory. Through automatic switching "under the supervision of a few electricians, the machines were started and stopped and messages were'sent in absolute eilence. , \~

The power now used was very nearly unlimited. A few .years ag" it had been ■deemed impossible, to : think seriously of plants of several hundred horsepower being attached to the aerial. Now there was not the slightest material difficulty in ibuildine- a transmitting set with a, possible power of over ICOO or 1500 kilowatts. By using th>i high-fre- ..." quency alternators designed by the French engineer Bethenod, units of 500 ' ■ kilowatts, giving over 80 per.cent, efficiency, could be obtained, and these machines could be' eleotrically coupled up so that the power used could vary from 500 kilowatts to 1000, if two were en ./^ ployed. These tremendous powers, whe; used for transmitting, were the best guarantee against atmospheric disturbances, and they ensured good audibility at an.v distance. ' The alternators used in the large French stations sent their power direct to the aerial without the help of multi- • plicators. The operator kept the alternator in a shorA circuit and transmission ■'■ of messages was effected by suppressing . the short circuit.