Untitled

New Zealand Listener, Volume 31, Issue 796, 22 October 1954, Page 24

Sir-Your comments on my suggestion for overcoming unwelcome interfer-

ence from Australian stations, though of interest, do. not im my opinion go even a fraction of the way towards remedying the position. You will recall that after Solomon’s broadcast with the National Orchestra from 1YC there were numerous complaints at this type of interference, some.even within the city limits, so that your claim that the transmitters in Auckland provide satisfactory service locally appears open to serious question, to say the least of it. Indeed, similar unsatisfactory conditions are reported to exist in the other main centres. Mr. A. Cushen, of Invercargill, has complained of considerable interference there, and he emphasises further that next winter this interference everywhere in New Zealand will be greatly worsened when new Australian commercial stations take the air and when several existing stations increase their transmitting powers. It is accordingly more than evident that now is the time for the New Zealand broadcasting authorities to take remedial steps. It should also be realised, as all amateur enthusiasts already do, that there are, in fact, several remedies for this very irritating interference from Australian stations. These are briefly as follows:(1) Increasing the power of the transmitters in the manner I have suggested would "enable unwanted background noise to be tuned down, and in the

case of 1YA and 1YC T am of opinion that owing to the dismal prospects for the coming winter a power of not less than 25 or 30 kw. in the aerials will be essential to "ride over" the Australian stations. (2) As previously stated, I consider it a complete waste of time to attempt seeking additional "clear channels" in the normal broadcast band, but if the New Zealand broadcasting authorities are really wanting clear channels they can have them by the dozen in the 1000 to 2000 metre band, which remains unused in the Southern Hemisphere. Thus, a long-wave station of relatively low power situated centrally in the North Island, and a similar station on a different wave-length in the South Island, each radiating the type of programme most desired by listeners, would overcome this question of interference completely. Such transmitters have been used very successfully in Europe since the earliest days of broadcasting, and were instituted with the very object of providing interference-free reception in out-of-the-way districts. For example, the Daventry transmitter of the BBC situated near Rugby and operating on 1500 métres, may be heard very clearly in all parts of the British Isles. This system would thus overcome the conditions complained of by "Countryfolk," of Upper Moutere, and the small cost of modifying existing sets would be well worth it. (3) The third possibility of overcoming interference is through the use of

Frequency-Modulation transmitters. As will be known, the BBC has for several years been operating such a transmitter experimentally at Wrotham, Kent, southeast of London. According to the latest technical journals received from England, this transmission has proved so successful in overcoming both fading and interference that the BBC is now erecting a F.M. transmitting station for general broadcasting services. Such transmissions, of course, require a different type of receiving set, designs for which are, however, available in this country. Surely it is high time that the broadcasting authorities got down to brass tacks in this matter without waiting for the inevitable barrage of complaints from listeners.

W. F.

CHUBB

Thames )

(The official reply is as follows: "A country with New Zealand’s topography and spread of population can be much better served by several medium-power, medium-wave stations, strategically placed, than by a few high-power stations. These medium-power stations have a limited service area, and it is wrong to suppose they are provided to give a multitude of alternative programmes for all listeners, wherever they may be. They do at times, however, usefully augment local station programmes, despite interference from electrical sources and from stations in Australia. Frequency modulated VHF transmitters have a much shorter range-almost limited to -‘line of sight’-so that many more would be needed. They would also have to be linked to studio centres by land-lines or radio links, both of which are costly; and listeners would be faced with the expense of purchasing new sets or adaptors."(continued on next page)