THAT SPLUTTERING RADIO

Taranaki Daily News, 18 February 1933, Page 6

THAT SPLUTTERING RADIO

extraneous noise search

NEW PLYMOUTH LOCATION SET.

THE CAUSES OF DISTURBANCE.

Holders of radio receiving licenses ars constantly handicapped through'-inter-ference by noise from all kinds of electric machinery when they increase amplification in the hope of bringing in a distant station, but the engineering branch of the Post and Telegraph Department is at work on the problem in New Zealand. The necessary directional radio apparatus has been received at New Plymouth and should assist the radio i inspector in locating the source of power interference with radio reception in North Taranaki. The apparatus is a portable receiving set housed in an oblong box, and the aerial is concealed in the door. The inspector takes the set with him in a car where assistance in the way of technical apparatus is required to locate a. source of interference. The hinged door containing the aerial is swung in. and out, and, according to the strength of the interfering noise at certain angles, the inspector obtains some idea of its whereabouts.' ’

Most countries in the world are tackling the problem with vigour, for it is acknowledged that the rapid development of-radio broadcasting and the substantial revenue derived, from licenses entitle listeners to protection from extraneous noises. In a recent Post .and Telegraph Department report reference was made to the work in; New Zealand. “The staff detailed for radio inspection duties has continued activity with: varying success in connection with the elimination of interference with broadcast reception,” stated the report. “At the close of the year extensive investigation was being made with a view to elimination of further sources of disturbance.” Interference can be caused by all kinds of electrical machinery. Leakage from a faulty insulator in a power line, trouble with a transformer, electric signs, streetcontrol signals and similar devices all disturb radio listeners whose seta are subject to their influence,. The radio inspectors investigate the causes of the noise after locating its source and suggest suitable means, of elimination .to. the authorities concerned. -■ A comprehensive display illustrating many of the common causes of radio interference and how to deal with them was staged at the recent annual radio exhibition at Olympia, by the British Post Office. A radio set was at work and a lecturer called attention to the ideal conditions which should prevail. Then electric motors were started on the stand, a traffic control signal began to move, and the resultant crashes and cracklings were heard at high amplification on the radio set. Explanations of the methods;; by which such extraneous noises could be cut out were given. Many household appliances were demonstrated to be guilty of causing interference, and officials gave advice on the subject, the wiring diagrams of suitable filter and choke units to eliminate noises, where within the control of listeners, being given to interested people.