Radio Review

Evening Star, Issue 19776, 28 January 1928, Page 16

Radio Review

[By “ HENRY.”]—

Flashes from Everywhere.

LOCAL STATION IMPROVEMENTS

Station 4YA was well up to the mark on Thursday night. There was an improvement in the transmission right from the gramophone concert in the early part of the evening to the studio concert later on. The gramophone items were decidedly better in tone, particularly pleasing being the depth and balance of the bass notes both in instrumental and vocal music. The studio items comprising the night concert were heard with unusual clearness, a noticeable point being the splendid enunciation which characterised all the singers. Ail this, I understand, was due to some Sinor alterations which have been made the studio in relation to microphone placing. Among the attractions on that night’s programme was Mr A. 11. AlJardyce’s 1 Prospects of Friday’s Racing.’ Mr Allardyce, by the way, was in town for the purpose of describing resterday’s and to-day’s trots at Forbury. Of course, all listeners will agree that the service from 4YA is gradually being improved. The artists are among the best the city can produce, and this week the sporting radio people have been well catered for. The occasion of the broadcast of the New Zealand swimming championships was the first on which 4YA lias relayed that class of sport. 4YA NOTES. A glance at the ‘Radio Record ’ reveals some good programmes promised from 4YA next week. The Kaikorai Band, under the conductorship of Mr E. Franklin, has a fine programme arranged for Tuesday evening, and in addition some firstclass talent will be presented. Mr Percy James will make his first appearance before the microphone, although he is one of the best-known men in Dunedin, and a comedian who has had many years of stage experience. The programme for Thursday evening should be most interesting, being of a really high class standard, and presented by artists of the front rank in Dunedin.

A GOOD CRYSTAL SET. Here are the particulars of the construction of an all-round crystal receiver, in which variation of selectivity can bo obtained, as given by “ Chris " in the Listener In. Those situated close to a broadcasting station can use a , certain number of turns between the aerial and earth connections to the coil until the proper degree of selectivity has been obtained. Those who are not so situated, and do not experience such between station interference, can bring into operation a larger number of turns, which will increase the volume of signals. This goes to prove that much volume is lost in the quest of selectivity. The parts necessary for the construction of the receiver are as follows: Piece of bakclite former, din diameter, Sin long. Reel gauge 18 tinned copper wire. Reel heavy twine. Aerial and earth terminals. ’PJione terminals. Two terminals to attach to the inductance. Semi-fixed crystal detector. Front panel. Wooden sub-panel. One fixed condenser capacity 0.001 mfds. One variable S.L.F, typo variable condenser, capacity 0.005 mfds. The coil should fir st be built. Securely anchor the beginning of the 18 gauge wire to a terminal attached to one end of the bakelite former. Also fix the end of the twine. Then wind a coil of fifty turns, the twine being wound on also, and spacing each turn. The other end may be fastened to a terminal fixed at the other end of the former. The twine may be removed, and the turns will be kept in place without shifting or spreading out if the turns have been put on tightly. If the winding has been loosely done, the turns may be fastened in place with Amyl Acetate, in which has been dissolved a small amount of clear celluloid. The layout of the parts can be left to the discretion of the builder._ Clips will be used to connect tire aerial and earth to the coil.

A talk on the prevailing fashions by » representative of the D.S.A. will be hoard on Friday afternoon, and instrumental music from the Savoy will be relayed. The Rev. H. E. Bellhouse, thairman of the Dunedin branch of the League of Nations Union, will be at the microphone at 7.30 on Friday evening, to speak on 1 The League of Nations—and a Warless World.’ At night there will be a high-class programme by several of tho most talented artists in Dunedin. Lovers of dance music may look forward to hearing the latest popular numbers, relayed from the Savoy, at tho close of the_ studio concert. On Saturday again a most attractive programme will be heard, several notable performers taking part, comprising Miss Irene Horniblow, L.R.A.M. (contralto), Miss Florence Sumner (so(prano), Mr R. A. Mitchell (tenor), Mr Arthur Lungley (baritone), Mr J. Stewart (flautist), Mr George Christie (cornetist), and Mr A. R. Watson .(violinist). 'AUSTRALIAN LICENSE FEE. As from January 1 owners of receiving sets in Australia have only been charged 24s by the Federal 'Government for a listening license. The fee is less than sixpence a week—less even than a penny a day. And for that amount listeners receive about fifteen hours a day of broadcasting. From 7 o’clock in the morning to 11 o’clock at night one or more of the Australian stations are on the air. For less than half the service New Zealand listeners have to pay 30s a year. Perhaps radio here would be more popular if there was a reduction in the annual license fee.

The wiring should be done as follows. Starting from the aerial terminal, take a flexible load to the end of which is attached a clip. The same is done from the earth terminal. One of tho end coil terminals connects to one side of the crystal detector, and also to one of the variable condenser terminals. The other coil terminal is connected to one of _ tho ’phone terminals, the second variable condenser terminal, and one of tho terminals of the fixed condenser. The final connection is from the remaining detector terminal,to the remaining ’phone, and fixed condenser terminals. The aerial clip should always be nearest the crystal detector, the earth clip being at tho opposite end. With such an arrangement it is possible to impress greatest possible voltage on the crystal detector, and thus secure maximum benefit from the receiver. AN AUTOMATIC SENDER. A machine for automatic code transmission. which apparently overcomes most of the shortcomings of other devices for the purpose, has been made in New York City _ (says “QST”). Its two principal virtues are its use of records which are too tong to memorise, and its ability to transmit at varying speeds without distortion of character. The records are in the form of perforated tapes which are cut on a machine which'is controlled by band sending. They are cut at various speeds, and, while they may be run at any speed desired, they are beautifully like the sending of a good operator when run fairly close to the speed at which they were cut. The result is that at all speeds the spacing and grouping are correct. The tape is used first m one direction and then reversed—two rows of perforations appearing on each tape. There are about 225 words on the tape each direction, making a total of 450 words per roll. Several rolls, cut at various speeds, are supplied with the machine, and additional rolls may be had at any speed wished. The fact that the tapes are so long gives tho machine quite a varied repertoire; an advantage apparent to those who have used machines where the records are soon learned by heart. A SUGGESTION. When putting the plate milliammater in a shunt feed circuit, he sure it is inserted between the radio frequency choke and the plate supply, and not between the choke and the plate. If it is pul next to the plate, it will be subject to the radio frequency currents generated in the tube, and will probably be damaged or even completely burned open. This suggestion is for those who want it in the positive plate voltage lead. Usually when a simple oscillator arrangement (to differentiate from oscillator-amplifier circuits) is used, the meter may be put in the negative high voltage lead, and will be nearer to ground potential. This is an advantage particularly if one happens to touch it when the juice is on. THE HOLLAND SHORT-WAVER. From Messrs Turnbull and Jones, Ltd., comes the news that the Philips Laboratories experimental station, PCJJ, is to carry out regular tests on the old wave-length of 30.2 metres hvery Wednesday and Friday morning between the hours of 5.30 and 8.30 (New Zealand summer time). NIAGARA’S WIRELESS RECORD. What can be claimed as a world’s wireless record was established by the R.M.S. Niagara during the recent trip from Sydney to Auckland, when, with a new short-wave set, direct communication was made between the ship and Burnham, England (says an exchange). Mr G. M. Power, the Niagaras chief wireless officer, stated that for some time he had been carrying out tests on short waves, and with the modern set which had been installed on the Niagara he experiences no difficulty whatsoever in talking with England. The messages travel between the two distant stations in one-sixth of a second for each letter. While the Niagara was running down the New Zealand coast on the way to Auckland the messages were received from Burnham as clearly as though they came from tho next room- This is the first occasion upon which _ any ship in the Pacific has been in direct communication for transmission with England. Messages are sent from the ship at the rate of lid a word._ It is hoped that two-way communication between the Niagara and England will be maintained permanently. CONCERNING CONDENSERS. The fixed condenser in a receiving set should have mica dielectrics fpr best results. Do not use condensers in which the dielectric is paraffin paper. For the best operation of a set it is important to make sure the condenser is of the proper capacity for the part the circuit for which it ia intended.

EGO REMODELLED. The Californian station, EGO, often heard in Dunedin, has been remodelled, and a number of mechanical appliances have been added to the plant. The frequency of EGO is now crystal controlled. In the adoption of the'crystal quartz oscillator for KGO, the General Electric engineers are using the most accurate method, known for maintaining frequency. It will now be impossible for the station to vary more than onetenth of 1 per cent, from its assigned wave length of 384.4 metres. Some new condenser types of microphones have been installed at the station. With tho new condenser microphone, organ music can be broadcasted successfully. It is impossible to “ blast ” this instrument, and the quality of tranamission is greatly, improved with it& use. RADIO IN SCHOOLS. Towards the close of last year an experiment was carried out by 2YA whereby a special educational programme was broadcast by the Wellington station, and received at quite a number of the primary schools throughout the dominion. Similar tests were carried out some time ago at Home, with the result that radio in the schools has now a good hold. The following paragraph upon the subject appeared in ‘ The Schoolmaster ’: — ‘‘ The growth of wireless outfits in schools is a development in educational facilities which cannot be disregarded. There are over 1,500 ‘ wirelessed' schools in London, 74 per cent, of which are elementary schools, and in the Midlands and East Midlands, as well as in the north, the weekly lecture Jby wireless is rapidly extending. The chief subjects dealt with are: Nature study, English literature, and music. Other courses by well-known experts have also been arranged. These are often followed by,written work sent up regularly by some of the schools. It is said that the training in listening for at least thirty minutes a week to a reasoned train of thought, and the stimulus to the imagination of th© children, have had a remarkable effect on the composition. The main difficulties of the schools appear to be those of poor reception, generally due to imperfect apparatus. Where difficulties of this kind appear, technical advice and assistance from the 8.8. C. is available. This is given free; either by letter or a personal visit. Further, if schools have the necessary technical ability to construct a set for_ themselves,- diagrams and specifications of suitable circuits prepared by their engineers for school reception are obtainable from the 8.8. C. headquarters or station director.” ‘NEW ZEALAND RADIO.’ The latest issue of ‘ New Zealand Radio ’ has been received. In this number there appears a helpful page for tho home constructor, dealing with the building and repairing of various radio components. Then there is an article on a radio-frequency amplifying Unit, fop obtaining more distant stations. The construction of the accessory is explained in full with accompanying diagrams. Other matter on Current topics, reception of various Stations, etc., should prove gssd readItapag to too anthasast.

* Henry" will be pleased to answer any questions through this column relating to the fascinating hobby. Each correspondent must sign his name and address (not necessarily for publication). Newsy items will be welcomed.

TELEPATHY BY RADIO., As a broadcasting stunt, a “ thoughtreading ” turn carried out by station 2BL, Sydney, in conjunction with Hoyt’s Theatre, a few days ago, was one of the most remarkable ever attempted. “ The Prophet Argus ” and his father, Mr C. L. Copeland, were the actors, and it was certainly mystifying for listeners in their own homes to hear questions asked by Copeland the elder from the studio of the broadcasting station, and immediately after hear the answers of his son, Argus, broadcast from the stage of the theatre a mile away (says the ‘Listener In’). Listeners had the assurances of five members of Parliament, whose voices were easily recognised, that the answers given by Argus were correct. A committee of half a dozen men from the audience of the theatre sat on the stage doing sentinel duty over the Prophet. One man at the broadcasting studio, well known in the radio trade, thought to puzzle Argus by showing his father a New Zealand tiki or charm, but immediately Mr Copeland, senior, called upon his son to sav what it was the reply came clear and distinct, and perfectly correct. Perhaps the most surprising part of the programme was the request made to the committee to think of a tiumber of musical items. This they did, and Argus, advancing to the piano on the stage of the theatre, immediately played the pieces. The items were five in number, ranging from ‘Bye, Bye, Blackbird,’ to Beethoven’s Sonata and Paderewski’s ‘ Minuet.’ From the point of view of listeners the turn was most interesting and mystifying, and althongh they could not see either the prophet or his father, the scene of one group of men and women in the broadcasting studio and the crowded theatre in another part of Sydney could readily be imagined. A CRYSTAL MINT. Below is given a useful hint to crystal set owners, and if carried out I should not be surprised if many readers find that reception strength is almost double. Some quite excellent crystal "detector stands are mounted on very inferior bases, made either of wood or of one of the nasty black compositions supposed to be ebonite. Good ebonite is, of course, one of the finest insulators known, but unfortunately the buyer cannot always be protected against substitutes, and much of the ebonite now sold has very little rubber in its composition. If in doubt as to the quality of the base of your detector, you will find it advantageous to remount it on a piece of really good ebonite. RECEPTION OF 3YA. On Wednesday night the writer spent an hour listening to 3YA, with the object of ascertaining how the Christ, church station was being received hero at present. Here are a few jottings that should prove of interest to those who have not kept in touch with 3YA lately. 8: Picture theatre orchestra relay; very clearly received; modulation good; entire absence of static. 8.13: Vocal quartet singing Britton’s setting of ‘Drink To Me Onjy With Thine Eyes ’ suffered from fading, and was almost inaudible at times; strength returned later, however, but the voices were not very clear. 8.17; Bass solo, ‘ Banjo Song ’ by Mr W. J. Richards; very_ clear and loud; still no sound of static. 8.20: Christchurch Broadcasting Trio playing the first movement of Mozart’s ‘ Trio in C Major ’; rather jerky at the outset but improved later; a good performance. 8.26: Elocutionary number (could not catch the name of the item or the performer); fairly clear. 8.30: Mr and Miss Mildred Russell singing Tate’s ‘Somewhere a Voice is Calling ’; horribly distorted at the beginning, probably caused by over modulation; improved later and became quite clear, 8.35: Miss Claris Shaw’s contralto number; good modulation; top notes very good. 8.38: Opening notes of Miss Irene Morris’s violin solo ‘Tempo di Minuetto ’ (an arrangement by Kreisler) were completely lost by a bad burst of static; except for slight fading item was excellently received. 8.43: Another vocal quartet; again the item did not come through as it should have; fading bad. 8.49: Contralto solo again ; strength of station returned and item came through distinctly. 8.52: Tenor solo, ‘ Take a Pair of Sparkling Eyes ’ (Sullivan); spoilt by slight fading; otherwise good. 8.55: A return to the picture theatre for a further relay of orchestral music; orchestra and station both in good form.

Returning to the studio the weather forecast was clearly given by tb© announcer, every word being caught. The race results following, however, were rather “ mushy.” Shortly after 9 o’clock station IYA Auckland was sought, but on a reliable and sensitive five tube set the station was just audible using phones. Static was so bad that it was not worth while hanging on to tho station. HERE AND THERE. The first contact between a Belgian and Hawaiian station was recently made by eb4WW. who was in communication for three-quarters of an hour with ohfißDL. A regular schedule has been arranged between them, and it is hoped they will be able to continue with these contacts. There are approximately 159,000 receiving licenses in the Argentine. It has been stated that additional equipment in the form of an equalising amplifier is to be installed at 2YA. This extra equipment, it is hoped, will remove most, if not all, of the trouble which has been experienced in connection with tho Wellington station. Recently 3AR, Melbourne, received a letter from a local radio man who stated that while on a trip to Japan he was able to keep in touch with 3AR during the whole of his journey. The radio and loud speaker seem to be displacing the scarecrow in a number of gardens these days, if reports in other papers are correct. . The Canterbury correspondent of ’New Zealand Radio’ writes; “The city of oat cakes has a station whose voice reaches Canterbury with the persistence the most pushing Scot could not beat. 4YA, too, has. forgotten how to fade, and as its programmes are as good as ever, the station is regaining rapidly the place it established in our affections during the Exhibition days.” Perhaps when we get a new station Auckland writers wul be in a position to" say that.

According to a Taranaki writer 4YA is board in that district as clear as a bell on 80 metres. The use of crystal and one valve receiving sets still predominates in Germany. This is partly due to the lower cost of these types; also the fact that there is only one broadcasting station in each Gorman city,_ thus making it unnecessary for receivers to be highly selective. I notice by the programmes that Vaude and Verne, who appeared in Dunedin sojne time ago, have been before the microphone at 3LO. Victorian listeners must have had many happy minutes with the versatile two. CORRESPONDENCE. “V.W.” (Dunedin). —The call sign of the station you asked for is 4ZB. The station is owned by the Otago Radio Association, and is on the air every Wednesday night. There is also another amateur station in Dunedin, 4ZM, which is going on Sunday afternoons. The other four stations are all situated at San Francisco. KFRC (Don Lee, Incorp.) is on a wave-length of 267.7 metres, and the power is 60 watts; KYA (Pacific Broadcasting Company) is on a wave-length of 413 metres, and the power is 1,000 watts; KFWI (Radio Entertainers) is on a wave-length of 294.9 metres, and the power is 500 watts; KGO (General Electric Company) is on a wave-length of SGI.2 metres, and the power is 6,000 watts. “Radio” (Palmerston.—lt is doubtful if there could be any improvement on the reception of the station you mention, as it works on a much lower wave-length than 3YA. J.M. (Mornington).—Good w.ork; aH the best of luck in the future.