Notes and Comments

Radio Record, Volume II, Issue 40, 19 April 1929, Page 26

Notes and Comments

By

SWITCH

A ‘GROUP of Wellington listeners were commenting on a _ recent evening on the diminution of the howling valve nuisance. The most feasible explanation was that the Australian stations are coming in with such volume that owners of "bloopers" do not have to push their sets to such a degree as to occasion oscillation. Wednesday evenings, when 2YA, Wellington, observes the usual silent night, the whole pack break loose and howl dismally either on top of 8YA or 1YA, not to mention 4YA, Dunedin, which is now of good loudspeaker volume as received by any fairly efficient multivalve set. ‘A RECENT return from Australia shows the following ratio of listeners to every 100 of the population of the various States of the Commonwealth: New South Wales, 3.87; Victoria, 8.07; Queensland, 2.68; South Australia, 38.93; Western Australia, .95; Tasmania, 1.99. For the whole of the Commonwealth the percentage of listeners to the population is 4.61, and the listeners’ licenses in force total 291,289. The more scattered nature -ar

of the population in some of the States has something to do with the smallness of the ratio of listeners. With the erection of more powerful stations, in July, which will reach out better, the ratio should quickly increase. Me. W. M. DAWSON, the Philips Lamps Company’s very capable yadiotrician, gave a most instructive and interesting lecture on thé pentode valve at the last general meeting of the Amateur Radio Society of Wellington. He is one of the most interesting lecturers the society has yet been favoured by, for he contrives to avoid that technical terminology which soars above the average gathering of amateur listeners. Mr. Dawson always carries the conviction that he is thoroughly conversant with every possible aspect of his subject. He also recognises the paramount importance of broadcast listening over all other features of radio. He is no faddist, but has a broad outiook on the whole subject of radio.

THE radio sketches put on at 1YA, Auckland, by Mr. Montague have captivated a large number of listeners. Possibly on some conveniént occasion when he is passing through Wellington that cultured entertainer may be heard from 2YA. Many of the sketches put on by the Australian stations are unsuitable for broadcasting if they are to be a complete enjoyment. In fact, one seldom hears a sketch from Australia that is entertaining enough to be followed throughout. THE recent attempt by 2YA, Wellington, to rebroadcast the Salvation Army celebrations transmitted by the shortwave station KDKA, Pittsburgh, U.S.A., was a creditable effort under most difficult conditions. KDKA was anything but strong at its best, and it came in with violent gusts. Although the endeavour was not a success, it was interesting to .all those who were fortunate enough to be able to be at home to tune in 2YA, All connected with the attempt did exceedingly well, and "Switch" sympathisés with them in being foiled by atmospheric conditions. THE writer has found through experience that the seeker of longdistance shortwave reception has a good deal to contend with. The spasmodie nature of the volume is anything but pleasing to the musical ear. As a source of interest when news is being received shortwave reception is exceedingly pleasing, especially when the particulars of some event of world-wide importance are being put across.

WELLINGTON listeners are delighted with the return of good reception from Australia. The transTasman stations have been coming in lately with any amount of strength, so that from, say, 10.30 p.m. onwards, owners of good equipment are able to nearly get a dozen Australians. Even 5CL, Adelaide, has become audible on the loudspeaker, and on a recent evening "Switch" obtained good entertain-

ment from band selections played in the distant capital. HIS is what a New South Wales country listener writes to the Sydney "Wireless Weekly": "Being in the position to hear many ideas of listeners, may I suggest that the evening programmes on Monday, ‘Tuesday, Thursday, and Friday be commenced one hour sharper. During the forthcoming winter months, I am sure it would be a boon to many'around these parts. The usual bedtime is 9 to 9.30 p.m., and if the big programmes were started at, say, 7 p.m., instead of 8 p.m., we could sit and listen to a good programme ‘before we became tired. I think you will find many who will back this up." The city listeners would raise ructions in New Zealand if broadeasting ceased at 9.30 p.m.

NEw Zealand listeners who chase after the American stations will be interested in what an Australian, Mr. Alan Burrows, who has just returned to Sydney from America, has to say about the Americans: "American programmes," he said, "have their bright spots, as the variety of talent is naturally very wide; and some of the ‘chain’ broadcasting is really remarkable. There are always world-famous artists from which to choose, who are usually willing to face the microphone-provid-ing their contracts allow them-so the arrangement of brilliant programmes is a comparatively easy job. But for the most part the programmes from the average station-well, they are certainly doing their part in the noble cause of ‘making the world safe for mediocrity.’ "

HIRE is no excuse nowadays for anyone to complain about bad quality of tone in receiving 2YA, Wellington.. New Zealand’s big station is delightful to listen to. If the tone is found to be poor then the trouble is located in the receiving set or loudspeaker. There may be various causes for poor quality of tone-wrong valves, wrong A, B, or C battery potential, poor type of audio transformers or an indifferent loudspeaker. The tone of a loudspeaker will in many cases be improved by connecting a .005 fixed condenser across the loudspeaker cords close to where they are plugged into the receiving set.

A LISTHNER complained that he was obtaining mych poorer reception of the Australian stations since he purchased a néw detector valve which was practically the same as his old one. Both valves were of high-class makes, but "Switch" immediately showed his friend that they possessed entirely different characteristics. The first valve worked efficiently with a =

quarter ampere filament current and 15 volts B battery, while the recent purchase required only one-tenth of an ampere A battery current but needed at least 30 volts B battery. It was bad salesmanship on someone’s part not to explain the difference between the two valves. Incidentally, the new . valve, through wrong filament current, and B battery potential, spoilt the tone of 2YA.

HE Melbourne "Listener In" gevofes a page of its issue of Apkl % to the constructional particulars, parts required, and schematic and lay-out diagrams of a certain circuit. ‘Then the information is added: "This circuit is presented merely for'experimental purposes, as it is very difficult to operate and very unstable. Also it creates interference. with other receivers. Usually the reproduction is distorted as a loud whistle is present during reception." Note the "interference with other receivers," ‘distorted reproduction, ete." Thank goodness the New Zealand regulations would bring down 4a prosecution on the head of any experimenter who operated such 4 set even "merely for experimental purposes."

AN enthusiastic up-country listener informed "Switch" that he pro-, posed to send direct to the United States for a certain much-advertised "B" eliminator. It had not occurred to the said gentleman that the American eliminators are wired for a line carryii : 110 volts, whereas his electrical supply is 230 volts. The eliminator would have to be specially wired for the New Zealand standard voltage, and such a departure from a big manufacturing concern’s standard would be a costly matter for the buyer. There are a number of proved successful ¢liminators wired for 230 volts on sale in New Zealand, and no one need send abroad for an eliminator. NOTHER American power valve will shortly be on the market. Its ratings are:-Filament voltage, 2.5 volts; filament current, 1.5 amperes; plate voltage (max.), 250 volts; pial current, 30 to 35 milli-amps; grid vol; tage, 50 volts; amplification factor, 3.5; plate reSistance, 2000 ohms; mutual conductance, 1750 micromhos; undistorted power-output, 1.6 watts (maximum) ; base, large UX; size of bulb, same as UX-210. The maximum undistorted output at 250 volts is practically the same as for a type 210 power valve at 425 volts. The new valve at its rated voltages will give over twice the undistorted output that can be obtained from a 171: power-valve at its rated voltage.