RADIO AND ITS RECEIVERS

Sun (Auckland), Volume I, Issue 191, 2 November 1927, Page 14

RADIO AND ITS RECEIVERS

Conducted fop THE SUN by C. M. Taylor, B.Sc., A.M.I.R.E.

LOCAL NEWS UNCLES AND AUNTS AT IYA A goodly list of men and women who are prepared to devote their time to entertaining the children is provided. Among them. Mr. Salt, as Uncle Peter, and Miss Constance Howard as Aunt Betty, are old friends from the original 1 YA. Mr. Hintz, whose humour has often amused the older ones, will be a decided acquisition, not only on this score, but also as a practical educationalist he should be of great service to the organiser in suggesting suitable stunts, which will do more than merely entertain. Any ! way, what would be wrong with a ferry boat trip round the harbour, an evening visit to the zoo, a tramcar ride to Onehunga and so on? One cannot help regretting that Uncle Bob and Uncle Sam, who did such yeoman service in the old days, are not again in the swing of things after their pioneering work in this field. Another popular uncle is Uncle Q., of station IZQ. This gentleman is the wellknown owner of Keith’s Radio Shack, Upper Queen Street; well-known to the listeners as a versatile experimenter as well as a keen radio business man. Mr. Keith filled in a big gap in our broadcasting service before IYA gave Sunday transmissions, and became deservedly popular with his talks to the little ones on Sunday afternoons. Alterations are under way at the station and a second studio will shortly be provided, thus supplying a much-needed want. The station manager is to be congratulated on the successful race relay of the Melbourne Cup yesterday. The local dealers are experiencing the quiet time which always follows the winter boom, and with the call of the open air which will follow daylight saving, the wireless set at home is going to have an easier time, but the demand for a cheap portable should be greater than ever, and town talk among listeners indicates that many are considering the purchase of a set for the holidays. THE SUN has one under construction and the design will be published later if it turns out as well as the early model promises. HIGHER POWER GAINING FAVOUR The Federal Radio Commission has adopted a policy of high-powered transmissions and as an outcome WGY. of the General Electric Company, has increased its power from 30 to 50 k.w., which is the maximum power allowed. This station works on 379.5 metres. Another station, VDKA, on 309.1 metres, also has increased its power to 50 k.w., and also KYW, the Chicago station of the Westinghouse Company, has increased from 1,500 watts to 5,000 watts. This station is on the 534.4 metre wave-length. The outcome of this increase in power will be in the nature of a static eliminator to many listeners, who will now be able to work their sets in such a state of insensitiveness that the high-power station will come in above the noiselevel of static and other interferences. KILOCYCLES OR METRES? A good deal of confusion has been caused among listeners by the announcement that the Washington Conference on International Wireless matters has decided to abandon the system of designating the transmission

t from a station in terms of wavelength, and to substitute the kilocycle system. Many listeners have immediately imagined expensive alterations to their apparatus to continue reception; but their alarm is needless, as it is merely a change in name—just the same as if the motor spirit companies suddenly decided to stop selling benzine, but would continue with the sale of liquid hydro-carbons. Confusion may arise, as many countries such as Great Britain, France, Italy, Russia and Switzerland still use the wave-length nomenclature, and the suggestion is to use both the wavelength in metres and the frequency in kilocycles in designating the transmission of any particular station. The system of metre-length expression is convenient and is used for that reason and the change is one of technical expression only. The wave used in transmission travels at the rate of- 300,000,000 metres a second, and if a wave has a length of 300 metres, obviously 1,000,000 would pass an observer in one second, so that one may make the change for oneself by using the fact that the kilocycle designation may be obtained by dividing 300,000.000 by the wavelength in metres and then dividing that result by 1,000. NOVELTIES IN PROGRAMMES. Part of the enjoyment of radio is the spice afforded by stunts which by virtue of their novelty make a direct appeal. Station SCL, Adelaide, has always been in the forefront in this respect, and broadcast one day last week an opportunity for motorists to try their aural keenness. A number of different cars from Fords to Rolls-Royces were lined up in a city garage and the sound of the engine of each car was broadcast in turn. To add to the novelty prizes of £3, £2 and £1 were offered for listeners who gave the correct list in its proper order. BATTERY TEST READINGS When reading the hydrometer used in the testing of a storage battery, the first essential is to have a reliable hydrometer, and, secondly, to read the maker’s specifications as to values and their precise meanings. A rough average is 1.275—1,300 battery fully charged; 1.260 about three-quarters full; 1.210 about half-full; below 1.18 the battery should never be allowed to drop, no matter what the make is. RADIO JOTTINGS There is now a total of 200,534 radio radio licences throughout Australia. Marconi was the first man to use an aerial and an earth system, and moreover his first experiments with the beam system were among his earliest efforts. All citizens in China who desire to have receiving sets in their homes must register at one of the offices in charge of radio broadcasting in Peking and Tientsin. Successful experiments were made recently of a conversation by radio telephone between an airplane carrying mails and a test station at the Bureau of Standards over distances of over 150 miles. A continuous report on weather and other conditions was SLinnlied to the pilot while on his journey. Austria is the first country to take up systematically the collection and supply of radio equipment and funds to furnish its sightless unfortunates

with the consolation of radio. There have been distributed 910 sets, almost all of the crystal type. Many people now have discarded parts of various types which might well be collected and put to a similar purpose here in Auckland, and built up into simple sets. What about it, fellow listeners? VOGUE OF ALL-ELECTRIC SET It is said on good authority that I 30 per cent, of the 1927-2 S models in ! America are of the lamp-socket type for all power, and to purchasers of this type of set perhaps a word of advice may help a little. It would be well for would-be purchasers to be guided by the advice of a merchandiser’s oracle, which recently sounded a warning to dealers, advising that they should proceed with the utmost caution in stocking alternating current receivers. “Consider the system employed, the construction of the unit and the integrity of the manufacturer,” is the suggestion. This is excellent advice to follow, not only for the dealer, but also for the public buying any type of radio set, whether it be electrically or battery operated. The great advantage of the lamp-socket set is in the fact that its powersupply is available by the snap of a lighting switch. Further, there are n-o batteries to charge or replace and the power supply is constant. The advantages pointed out for the battery receiver are “pure direct current.

steady, quiet, noiseless, uniform operation, taking: nothing - from and adding nothing to radio reception—no line troubles or. blown fuses to stop .reception—you need never miss a single concert.” DON’T HAVE UNTIDY SET When a set is used purely for broadcast receiving, and is free from the attacks of the family experimenter, there is no reason why it should not be an addition to the furnishing of any room, and not a tangle of untidy wires and batteries. A neat cabinet, designed to hold the batteries as well as the set, is well worth while. Modern speakers, by reason of their design and musical qualities, assist towards broadcast reproduction, which is entirely free from the old conception of wireless. A set is now a musical instrument no less than the piano and organ, and deserves to be regarded as such. , There was a time when it was necessary to burn a quarter of an ampere of current at six volts before a valve would show much sign of life. The ‘‘.o6 amp.” valve was thep introduced, but this, except for occasions when very low consumption was necessary, as in portable sets, was rather too little for all-round purposes. They were, and still are extremely economical valves, but they lose correspondingly in efficiency. A compromise has been reached in the almost universal adoption of “.1 amp.” valves, which use only onetenth of an ampere, and are so efficient that they will almost do the

work of those using many times that amount of current. The lower voltage—4£—has almost become standard, too, so that a general all-round saving in battery consumption ha's been effected. One result has been increased popularity of .portable sets. It is doubtful, however, if the modern dull emitter is as robust as the older bright valve. Their nature demands that the filament be frailer; and, moreover, it is coated with thorium. which gives the valve its extreme sensitivity while the filament is still at a comparatively low temperature. Burning the valve on a higher voltage than that intended, ov accidentally connecting the “B” battery across the filament—if it doesn’t blow the valve out —will ruin its emission more than months of use. Dull emitter valves have come to stay, but their popularity would grow still more quickly were they treated with greater care, and so made to give better service and to last longer.

OLYMPIC GAMES TO BE BROADCAST It is announced that the Sydney station, 2BL, has completed arrangements to broadcast description of the events at the Olympic Games to be held in Amsterdam about July next year. Descriptions of contests for the various world’s championships and particularly those in which Australians and New Zealanders are engaged, will be broadcast by PCJJ and relayed by 2BL.