RADIO RECEPTION INTERFERENCE PROBLEM

Taranaki Daily News, 27 September 1933, Page 5

RADIO RECEPTION

INTERFERENCE PROBLEM

NEW SCHEME SUGGESTED. COMPLAINTS “CLEARING HOUSE.” recommendations that the Post and Telegraph Department should act as a clearing-house for complaints of interference with radio reception and that regulations should be made for the control of apparatus disturbing broadcasting reception were made yesterday at the annual conference of the Electrical Supply Authorities’ Engineers’ Association. A special committee had been set up to, report on radio interference. At the last conference a resolution was carried that, while recognising the' importance of radio broadcasting, the association considered that the activities of supply authorities should be limited to remedying interference originating from supply lines or apparatus under their control, and then only when such remedial measures were warranted and could be economically undertaken.

In presenting the report, the chairman, Mr. George Lauchlan, explained that the Government had set up a committee which included representatives of power board and supply engineers to report on radio interference. They were: Messrs. Cl S. Plank (Post and Telegraph Department), R. Gibbs (late chief engineer, Post and Telegraph), H. Miller (Public Works), and himself. They had the report of the joint committee of the National Electric Light, Electrical Manufacturers’ and Radio Manufacturers’ Associations before them. It dealt with the use of higher power broadcasting stations to improve general reception, proper installation of sets, the use of radio frequency filters, and the setting up of ordinances which in a few years became a

hindrance instead of helping to a solution of the problem..

ALLOCATING RESPONSIBILITY.

The recommendations made by the committee, said the chairman, were along the lines that the P. and T. Department should act as a clearing-house for complaints of interference, and should investigate and allocate the responsibility for the removal and alleviation of interference. It was suggested that the department should co-operate as far as practicable with electric supply, and tramway authorities and users of disturbing electrical equipment with a view to suggesting remedial measures. It was also recommended that further regulations be made requiring anyone using apparatus causing disturbance to remove the cause or take such remedial steps as might be considered by the PostmasterGeneral to be reasonable in the circumstances.

It was also considered desirable that there should be a prohibition of the installation of domestic and other appliances capable of acusing interference with broadcast reception unless supplied with means for absorbing and preventing the radiation of high-frequency oscillations. In the opinion of the committee, said the chairman, the most satisfactory way to give effect to that recommendation would be to prohibit the sale of such appliances by control of importation or manufacture in the Dominion.

To deal with cases of appeal from the decision of the Postmaster-General, it was advised that a special committee consisting of qualified engineers representing the P. and T. and Public Works Departments, the Broadcasting Board, and electric, light, power and tramway undertakings should be set up. Recommendations such as he had outlined, said the chairman, would protect the interests of supply authorities. He moved the adoption of the report. Mr. L. B. Hutton (Southland) drew particular attention to the finding of the American committee which said in no uncertain manner .that ordinances issued in the past relating to radio interference had been generally ineffective; in

other words it was a warning to “go slow.” The local committee, in its recommendations, made no reference to the payment of cost, and it would be interesting to know who would pay in the case of an investigation directed by the P. and T. Department which had proved of no value.

Mr. Plant agreed that amendments to the Act were desirable so that regulations could be made governing the matter. Up to-now the policy had been—and would possibly be so in the future—that the P. and T. Department had investigated complaints of radio interference. Just before coming to the conference he had obtained some figures showing the number of reports on interference received in the past six months, and the list would give the delegates some idea as to who the culprits were. They were as follow: Power lines 354, faults in complainant’s own receiver 214, trams 57, motors 71, street lighting, etc., 69, medical apparatus 33, picture theatre rectifiers, battery chargers and rotary converters 2G, domestic appliances 6, miscellaneous (neon and flashing signs, railway bells, electric welders, milking machines) 44, trees touching power lines 22, miscellaneous P. and T. services 63 (including morse signals 22, and telephone dialling and ringing 11), amateur radio transmitters 36, howling valves 90, unclassified 110, complaints not justified 54; total, 1249. In regard to trams the department was not getting the number of complaints that it should, continued Mr. Plant, but experience told them that something could be done to reduce interference in that I direction. In connection with the evils mentioned every possible assistance was given by the department. Power boards and power engineers would realise that it would pay to assist in removing the troubles and causes likely to create a nuisance to radio service. The speaker referrred to particular types of interference which occurred at Palmerston North and Napier. In one case the complaint was in regard to a motor, and the owner refused to make any adjustment or to allow any inspection. The Government should have the power to compel such an owner to adopt remedial measures, in ‘order that the plant should not annoy

people in the neighbourhood. It was hoped that legislative action would be taken during the session. Mr. H. F. Toogood (Wellington) agreed that- the increased use of higher power broadcasting stations would ensure a better coverage of the country, higher field strength for most communities, and would improve general reception. Some trouble was caused in trying to get distant stations with attenuated reception. If there were two stations operating in an area there would be a flattening of reception under certain conditions. The Broadcasting Board should take into view the fact that stations should be a reasonable distance from the cities and in Wellington should be at the back of the hills. Then a good deal of the trouble regarding interference would be over. He commended the report of the committee for serious consideration, for they should make an early start in trying to solve the problems. The P. and T. Department would act as a clearing house in order to get better reception throughout.

There were some classes of interference which no station could overcome, said the chairman, and the object of the report was to get over that. Now was the time to do it. . They were agreed that the P. and T. should be the clearing house, ahd now knew where they were. The report and recommendations were then unanimously adopted.