WIRELESS

Nelson Evening Mail, Volume LXVI, 29 July 1933, Page 11

WIRELESS

GENERAL NOTES ATTACK ON INTERFERENCE EFFORTS IN NAPIER A task which will necessitate a great amount of work and trouble, but which will be attended by definitely beneficial results as it progresses, namely, the elimination of the multitude of causes behind radio interference, has been undertaken in the Napier district by a special officer attached to the telegraph engineer’s department at Napier (says the Napier “'Daily Telegraph”). Although the work has been carried on to a limited extent for some time, it is only recently that an active campaign against this nuisance has been commenced. 1 These investigations have been made possible by the appointment of a radio inspector, for the district, his principal duty being to inquire into all complaints received from owners of radio sets who are experiencing interference. Previously, the work had to be carried out as far as possible by officers of the telegraph engineer’s department working in their spare time, and in consequence the nuisance could not received the attention required. With the appointment of the radio inspector, however, it is anticipated that a change for the better will rapidly be brought about. , A very large number of set owners in the district have found interference all too evident at various times, and as a result they are ready to welcome with open arms any endeavour to improve the position. It is emphasised, however, that there is a very great deal of trouble of this description in Napier, and its elimination will require investigations over a fairly long period. The causes of the nuisance are many and varied, but some of the most common are:—A surge from a motor in the vicinity; faulty fuses on high-ten-sion or low-tension lines; a '‘howlling” set; faulty switches, or fuses; electrical appliances such as vacuum cleaners, and kettles; a loose, swinging aerial; a badly-joined or loose wire connecting a set with the earth, or ns the result of filaments of street lamps breaking down and arcing. There are -also numerous other causes. In the short period during which he has been operating, the officer appointed to search for the interference in the cases which come under has notice, has succeeded in covering a very wide field. For the purpose of locating faults, he is equipped with a special portable receiver—a highly sensitive instrument, equipped with a “loop” aerial —and already the results obtained have been very satisfactory. The question of where the' necessary finance to maintain the fault-locating service was to come from had not as yet been clearly defined, the officer stated in an interview, but this would no doubt be covered in tlio proposed regulations. At the present time, set owners were being asked for help in providing the funds to defray the

cost of the service, while owners of motors were also being approached l to see if they were willing to do their share. Generally speaking, these people were working harmoniously together in attaining the desired object. It was pointed out that when complaints were lodged by set-owners, it was necessary for the type of interference being experienced to be statod clearly, and. tor any information calculated. to be.of assistance 1.0 the radio inspector to be communicated to bin?. Endeavours were made as soon as possible to trace the trouble to its source, after which filters or other devices were fitted to bring about its elimination.

Will Not Insult Decent People. ‘“The Australian Broadcasting Commission cannot be dictated to on important questions of public policy by the whims of the. artists whom it employs.” said the general manager. Mr W. T. Condor, when referring to Miss Dorothy Brunton’s refusal to take the leading part in a broadcasting production because certain oaths were exorcised. ‘‘The listening set is a much more intimate affair, entering into almost every home, and forming a part of the fireside life of the community. The commission cannot afford to, and does not intend to, insult decent Christian people, least of all in their own homes.”

Getting the Right Sounds. Fortunately, regular musical sounds and the sound of the voice are reproduced very faithfully; it. would be very awkward if they weren’t! But some other sounds, particularly what are described as ‘“effects,” come through quite differently from the original. For instance, in a talking picture in which an egg was broken into a frying pan, the noise over the microphone sounded like the roar of a cannon. The correct sound was eventually got by thq crushing of an 'ordinary small matchbox. , ■

For a battle scene the sound of rapid firing machine guns is produced by slapping a leather cushion with two flatwooden sticks. The roar of a cannon is made by striking a brass drum with a padded stick (or by breaking an egg, as above!), while the whining of an aeroplane propeller is imitated by holding a piece of light paper against the blades of an electric fail, the fan being moved to and fro to produce the effect of an aeroplane approaching or receding. The crackle of a burning wooden building is produced by crushing a piece of transparent wrapping paper in the hand close to the microphone. Sounds of the surf rolling on the beach are made by rolling small lead shot backward and forward over a cowhide frame.

Selecting an Announcer. When the French private station Radio-Vitus, at Paris, announced that the position of announcer was vacant, 3,000 applicants (including five ladies) offered to fill the vacancy. Among these applicants were the winner of a French “Prix de. Romes” for Architecture, some lawyers, and a number of literary men. At the first examination no less than 270 applicants were eliminated. Further examination reduced the number of remaining applicants to twelve, and six of these were finally appointed by a special Examination Committee to speak before the microphone to enable listeners to judge of their merits. Votes are to be cast by the listeners in order to decide who shall be finally selected.