Radio Broadcast (May-Oct 1922)

252 Radio Broadcast to have the messages from the fishing vessels transmitted as rapidly as possible, the French postal authorities, who are in control of communication systems in France, have them telephoned direct from the coast radio stations to the owners. La Rochelle is the. only fishing port of importance which is not yet provided with a radio station, although some forty trawlers of that port are equipped with radio. At St. Pierre and Miquelon there is not as yet a sufficiently powerful coast station, but an up-to-date equipment with a radius of 600 miles is expected to be installed during the next season. WHAT IS A RADIO OPERATOR? FROM the London Electrician we learn of a dispute that has arisen between the Association of Wireless and Cable Telegraphists which has a membership of between 5,000 and 6,000 (95 per cent, of the total of British wirelesss operators), and the London District Association of Engineering Employers, representing the shipowners and the wireless companies. The men's secretary states that, in addition to a reduction of wages, the telegraphists were to be called upon to perform "other duties" besides telegraphic work. They had attempted to get a definition and a conference, but only a vague reply was given which would leave them entirely at the mercy of the shipowners and the captains. The question of wages alone could no doubt be satisfactorily settled. The men had been instructed to refuse to sign on any ships, and already 300 to 400 men were out. No doubt by the time this is read the trouble will be over, but the fact remains that a radio operator is often called upon to do work quite foreign to his duties as a radio operator. So the question: What is a radio operator? THE INTERNATIONAL LOUD-SPEAKER WHEN our loud-speaker enables us to hear radiophone broadcasting stations sevveral hundred miles distant, we believe we are doing very nicely, do we not? Well, in Europe they are doing still better, and taking it more or less as a matter of course. While we have made remarkable progress in the transmitting end and in the introduction and working out of the radiophone broadcasting idea, it appears that the Europeans know a little more about radio-frequency amplification than we do — at least they make more use of it than we do. For instance, it is reported that a loudspeaking radio telephone receiving set has just been completed at Lausanne, in Switzerland, which gives the radiophone concert sent out by the Eiffel Tower in Paris, a good 500 miles distant, as well as the stations in London and Berlin. The high-power radio telegraph stations of the United States are also being picked up by this receiving set and made audible throughout a large room. EXPEDITING PORT BUSINESS WITH RADIO THE radio telegraph stations which have been installed in the port office of the French inland city of Rouen and on certain pilot boats by the Rouen Chamber of Commerce have been officially put into service. These installations will be used exclusively fgr transmitting messages relative to maritim.e affairs, promotion of the port, and services for and of the port. The pilot boats equipped with radio will keep the port office informed of the arrival of vessels coming up the Seine River on every tide and will be instructed by the port office in regard thereto. Merchant vessels not equipped with radio and having urgent dispatches to transmit to local ship brokers before docking can do so through the port office, via the pilot boats. Other radio messages or dispatches not relating to navigation or the port of Rouen and its services must be sent through the public radio station at Bleville. MAKING THE TELEPHONE RECEIVER MORE SENSITIVE NO LESSER authority than G. Seibt of Germany has found it possible to increase the sound intensity of a telephone receiver by laminating or subdividing the pole pieces above the poles of the permanent magnet and by introducing a magnetic shunt or by-pass for the magnetic flux, just below the coils, according to Elektrotechnische Zeitschrift. The pole-piece divisions or laminations are made of 4 per cent, silicon steel. The magnetic shunt air gap was found to be most effective when set to about 2 millimeters. The diaphragm is made of the same steel as the pole-piece laminations instead of the previously used American ferrotype steel. Tests made with such receivers showed an increase of sound intensity' of from two to two and four-tenths times that of the old model. The new receiver is already being m^de on a large scale.