Radio Round the World

Radio Record, Volume III, Issue 35, 14 March 1930, Unnumbered Page

Radio Round the World

"| WIRELESS station reputed to be "" the most powerful in Europe was opened recently at San Palomba,.a suburb of Rome. The broadcast programmes, which will comprise concerts, lectures, political speeches, news, dance music, and excerpts from the theatres. will be chosen by a speial committee with:a partieular view to interesting listeners from abroad, Its power is fifty kilowatts, but a special type of transmitting valve of 100 kjlowatts allows for a very large margin of maximum modulation power, and during transmission a power of 200 kilowatts is reached. Another innovation is the use made of a mereury vapour rectifier in fhe power snpply circuits, which allows for 9 fe: cent. efficiency in converting the aYernating current to direct eurrent. APPARATUS designed to transmit ~ pictures, weather charts, and maps te aeroplanes in flight has been successfully tested. in Cologne. First a weather chart was transmitted, enabling the pilot to determine conditions likely to be encountered on his route frem Berlin to Cologne. The position of a heavy thunderstorm ‘next was sent, and the pilot was able to estimate the speed of the storm and the time he was likely to encounter it, The third pieture was that of an airport, part, of which was fleoded, and from the pietyre the pilot picked . a suitable landing spot elsewhere. An exact weather chart, much more yalyable than a detailed vepert, may be ~~ ransmitted in three minutes, while sending the detailed, repert takes a mueh lenger time. ROM Sweden: comes a report of the first case ‘ef’ international waye-snatching in the records of European wireless. For some time past Swedish listeners, have been conseious of trespass upon, their allotted strip of ethereal sea, and they have not taken the affront:lying down, Their Government has put-a posse ef radio police upon the seeni--or rather the sound---and the pirate has been deteeted. The interference is said te come from the capital of a Central Furopean State which, not centent with the wavelength provided fer it by international agreement, has annexed that of another country. The Swedish radio authorities, owing to the lack of space in the maze of ethereal traffic, are unable te change

their awn wavelength. . They have now, however, given the Swedish radio listeners the comforting asswranee that. fS SQQR AS the latest and mest powerful of the Swedish transmitting stations is completed it will be strong enough te drown the freebooter and even compel his adherents te listen to Sweden whether they want it or not, CCURATE pictures of a flash of lightning, which lasts only an infinitesimal part of a second, now may be taken with an extremely sensitive eight-day camera known as the "klydenograph." ‘Phis camera records the pojarity, magnitude, steepness and diveetion of travel of lightning surgés. A clockwork device antematically turns the roll of film and reeords the time of the flash. It needs no care except the weekly change of film, The instrument is to be used in connection with research work yndertaken by an American engineer to discover the ronnection between thunderstorms and atmospheric interference in radio reception. "TALKING pictures have been sue- _ cessfully utilised by the Philadelphia police department as an aid to fighting crime. The police, besides making sound-films of eriminals ta assist them in identification, have also used the equipment to reeord the confession of a crime in. an effort to show that the criminal was not tricked inte admitting his guilt. Talking pictures of police characters, criminologists believe, would be a great aid in identifying them, as the yoice and various views and postures would supplement the erdinary front and side views of the suspeet taken by the police photographer. N° sure means of locating submerged submarines has yet been devyeloped, although yarious types of listening gear have proved moderately effective. Statements recently have been made, however, that the British Admiralty has developed apparatus for locating submarines at a distanee. Such a device, if perfected, would mean the end of undersea fighting craft, but the range of listening gear used in all the navies of the world, so far as is known. is measured in hundreds of yards.

vather than miles, so that, unless the sea were alive with scout boats, many submarines would escape deteciion.: A large proportion of the devizes in use af present for locating submarines de pend on the propagation through the water of beams of sound waves too short to be aydible to the human ear. They differ from audibie sound wiayes in that they can be divected along a comparatively narrow path, and can be produced . from electrically excited erystals of quartz, similar to those used in radio transmitters. These sounds are reflected as ec)oes from solid objects, and are pieked up by delicate and highiy-complieated radio receiving apparatus, passed through amplifiers. and are finally interpreted by trained observers. A PAIR of head phones, the earpieces of whieh are built to fit into the listener's ear channels, form an interesting part of the equipment of an American flying radio plant. The latter consists of a hugh tri-motored all-metal monoplane, elaborately-equipped as a radio isboratory -te test radio transmitting and receiving sets for pilots. The ‘plane will also be used for research work in connection with the development of radio apparatus for airevaft communication, from the earliest experimental stages to the final testing of the finished prodyect in actual flight. (COMMUNICATION reaching almost from the North to the South Pole was established when the _ northernmost Soviet radio station in Franz Josef Land carried on a conversation with the radio station at Commander Byrd’s Antarctic base, over a distance of 12,500 miles. This is a new record in long-distance communication, The Americans informed the Russians of Antarctic weather conditions and of their future plans, and inquired about the seareh for missing American aviators. ITHOUT a knowledge of vadio or of code signal, it is now possible for any person, no matter hew ignorant of radio, to send out distress signals, from a ship or aeroplane, The signal automatically gives the position of the craft and its call letters in the inteynational radio code, The automatic device was invented by Lieut © A, Perez, of the Cuban Signal Corps, and it recently was tested before U.8, Navy officials, All that is necessary fo operate the transmitting device it is explained, is to plug in the correct latitude and longitude indications, they throw a switch. Complete, the instrument weighs only fifteen pounds, and is about the’ size of a portable typewriter, Because of its compactness and light weight, the inventor expects it to be used widely in ‘aircraft. HUGE bonfire composed of obsolete radio sets was witnessed reeently by an interested crowd in Philadelphia. One thousand reeeivers of qgll designs, varying from humble crystal sets to eight and. nine-valve super-heterodynes, were destroyed to relieve the glut of old-fashioned radio s¢ts on the market. Dealers made gencroys allowances on every set brought along by owners to he burnt, provided a veceiver of more modern design was purchased. Lo,

SCREAMS and cries of "Let me. go!" were heard comizg from an appat~ ently empty house by a horrified Jndon resident recently. Three police oificers were hurriedly summoned to fhe seene-only to discover that the sousids heard were emanating from a loudspeaker owned by the caretaker of the puilding. They were part of the dialogue of W. W. Jacob’s play, "The Monkey’s Paw," which was _ being broadeast from 2LO. UMOURS are current in England at present that as a result of the recent linking together of the Marvéni and Gramophone Companies the sale ‘of wireless sets may pass into the hands of the music trade, and that after a while we shall go to the mysiec shop to buy our valves. Such a change, however, need not be feared. The working and maintenance of wireless apparatus, combined with the diffienlties of servicing, are far too compiex to be handied by an inexperienced retailer, and for him to attempt to sell to the equally inexperienced customer ig truly a case of the blind leading the blind. Tet us Jeave wireless to the wireless trade and avojd the mistake of arousing prejudice when presenting new equipments to the wireless-inter-ested public, The voice of the enthusiast is a strong one, and the unsatisfactory results of the handling ef radio gear by unskilled salesmen will rouse his resentment,