NOTES AND COMMENTS

Radio Record, Volume I, Issue 43, 11 May 1928, Page 8

NOTES AND COMMENTS

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HE A.C. ghielded-grid valve has arrived. The New York "Popu- , lar Radio,"of March, says:-"In the February number of "Popular Radio" the editor suggested that the next logical development in radio would take the form of A.C. shielded-grid . Valves. Before the ink was dry on that paragraph, one of our genial friends popped into the office and proudly exhibited the finiched article. . Suggestions to-day, realities tomorrow!" CANADA hag sixty actual transmitters but more than that number of stations, because several stations are dividing the use of a single transmitter. ° . # A Russian Lullaby" ig well knowa to New Zealand listeners. The charge that one of Irving Berlin’s . outstanding song successes had been "pirated" from manuscript submitted to Mr. Berlin’s musical publishing house was contained in an action filed recently in the New York Snpreme Court. Ira B. Arnstein, a composer, said that he privately exhibited a song entitled "Alone" to the Berlin firm and that shortly after, in April, 1927, "A Rusgian Lullaby," by Mr. Berlin, appeared. The music was plainly that of his song, which as never been published or copy- ' righted, Mr. Arnstein asserts. He * adds that he has common-law rights in the music which he wants enforced His action seeks an accounting for the profits from "A Russian Lullaby," by Mr Berlin and his firm, and asks an injunction prohibiting further sale of the song until the action is settled The publishin;s house demands a bill of particulars of Arnstein’s claims iWiITH the help of radio photography the long arm of the law reached acrosg the Atlantic recently to capture a criminal in London who was wanted in Chicago An exchange ' of fingerprints between Scotland ‘Yard and Chicago, by means of ra. dio, identified the fugitive, and tho British authorities returned him to America to stand trial ‘A correspondent recently wrote to the Melbourne ‘"‘Listener-In" :- Please explain the following: When I disconnect the aerial from the set and hold it near the aerial termina! screw, about three inches away, the waves will jump the gap and still get into the set Why doesn’t the same thing happen in a lightning arrester where the gap is tiny? ID. (Horsham, Viec.). The Editor replicd: The waves do not jump the gap, but reach the set through the ground, The wiring and coils in the set also pick up some energy, just like on aerial, and that is why some receivers will operate without aerial and ground connections. The incoming radio impulses are very weak compared with the static charges, which are powerful enough to jump the air gap in the arrester. (WHAT is an electric receiver? Although this should be a simple question to answer, there scems to be a great deal of confusion jn drawing conclusions. The New York "Popular Radio" holds that any receiver drawing itg source of supply, both "A," "B" and "C," from the lighting mains through "A," "B" and "C" power devices without the use of batteries of any type, may be called an electric receiver. It would seem superficial to use this term only in connection with sets employing AC valves, After all, the term "electric set" ig more or less ambiguous, for all radios are certainly electric, Perhaps the term "hbatteryless receiver" would be more correct, although it is a negative term. ‘A convincing foretaste of future business hustle is provided br the newg that an eight million pounds prospectus of the issue of the Province of Buenos Aires 6 per cent, Bonds was recently sent from New York to London by photo-radio-telegraphy for publication in French newspapers. The reproduction of the prospectus in a Paris papernearly a page-was so clear that it did not need to be re-set in type, but was just photographed and printed A writer in London "Popular Wireless" says:-The little lyre-bird whispers that the listener in Andorra (kindly look at the map of Spain to find this independent municipality) has failed to pay hig license fee for 1928, and as he still insists upon listening, because he is the mayor, has been fined a couple of goats or fourteen strings of onions, payable by instalments. Talking of "pirates" it is said that India is in a bad way through lack of license fees. But our Eric Dunstan is putting up a good fight. I am not a wet blanket, but I know a little of India, und in these "Notes" I predicted wholesale piracy a long time ago.

-a saving 01, say, a week’s time. Marconi has predicted the abolition of Morse, and it now seems that, for business purposes, he has the right idea, wINCE the inception of radio communication, engineers have ace cepted the theory that static interference igs a phenomenon associated with the atmosphere and that the visitations of static impulses is the direct result of exposing parts of our receiving apparatus to the air. It has been insistently imagined that these rebellious gushes of statie strike our aerials and rush pell mel] through our receivers to the ground. How shocking it would be if we had to revise this conventional notion and picture static as a ground phenomenon, with terra firma as its abode in place of the sky. Such is the astounding theory of Dr. Richard ‘Hamer, of the Pittsburg University, U.S.A., whose researchs have supplied what would seem to be sound verification for this amazing conclusion, Many scientists, however, will have their doubts, notwithstanding Dr. Hamer’s deductions. A London writer says:-The great Galli-Curci has at last sung before the microphone; she was the last of the die-hards in the top-notch singing line. When asked why she hung on so long, she said that she was waiting for radio to be perfected, Gentlemen, radio is now perfected, but what a pity some of them did not wait till the gramophone was--cr-had reached its present degree of goodness. FACILITIES for radiotelephone service from ship to shore will soon be offeed to all spassengers aboard the Hamburg-American liner "Columbus," according to ‘"Radiowelt," a German radio magazine, The new service, which is announced to begin in May, will enable those aboard the ship to sit in the comfort of their cabins and converse with parties in New York, or Berlin, as easily as one converses over an ordinary telephone. Only first-class cabins will be equipped with private connections; second and third-class passengers must use the radio room or telephone booths which are provided on the ship. People on shore will also be able to talk to passengers aboard the vessel. A friend in Bere lin picks up his telephone and Says "Please connect me with Mr. X, aboard the s.s. ‘Columbus.’ " A while later Mr. X is called from the diningroom to the telephone and hearst "Achtung, Berlin kommt" (Berlin on the wire),, and the conversation from ship to shore begins. WORLD-WIDE tax information indicates that radio is classifield in almost every nation on the earth as‘a necessity, and not as a luxury. France and Spain alone classify radio as a luxury in their taration programmes; France levies a 12 per cent. tax on more expensive sets, and a 2 er cent. tax on cheaper products, while Spain has a 5 per cent. ad vatorem rate. About a dozen couns tries levy a sales, or excise, tax, ims posed generally on almost all pra ducts, ineluding radio. MR. Max Howden, the well-known * Melbour e amateur transmite ter, reports:--On the 20 imetre band the most interesting listening is perhaps to the broadcasting prosramme from 2NAI, the G.E, Co.'s short-wave station, that works on 21,4 metres. This station is very easy to pick up at dbout 9 am. (109.30 a.m. New Zealand time), when every word is clear, except when fading is particularly bad, ‘There are several other broadcasting stations using waves fairly close to this, but they de not work so regularly.

wir seventeen out of every : twenty-six homes in the United States wired for electric lights, the future of the all-electric sets in ‘that country looks roseate. in the extreme. "whe seventy-frve million | people whom these homes «epresent are « market that has barely been touched hy the newly-developed alelectric receivers and other power de‘vices that operate from the lighting ‘Tines, And since the number of electrieully wire bouses is imereasing yearly (the increase im 1927 was Th per cent.)J, it can be seen that socket operiution for raidie receivers is in ifor 2 lomy and heppy period of pros- : perity. EZ is purposed to erect several intermediate radio transmission statiows in Ereland, in addition to those already existing at Dublin and Cork. The mumber of Licensed reeetyers now ex¢erds 9,600. rN the Wnited = Stetes, radio's total volume of busine. hist year was 55C 800,600 dollars (110 million pounds), ranking it sixth among the industries of the country, This astounding tolal hes been reached in a sever-yerur boom from the 2,000,000 dollar (£100,000) business 0. 1921--the mest phenomenal industrial growth in bistory. In 121 the Dusiness consisted largely in crystal sets and three-cirenit tuner,. In 1922 came the nentrodyne receiver, using four and five valves, raising the business fo 2 GO.000,000 doliars — (£12.000,000) level. Tn 1923 the total was 150,000,000 (£70.000,000), in TOL $50,000,000 (£70,000,600), amd in 1625 -£40,000,000 (£82,.000,.000), In 1925 the niinufacture of six, seven. und eight-valye receivers brought the total to almost the half-billion murk. and 1027 tool the tofal well above that level. During WT six-valve reecivers proved to be the best sellers.

ante, dee el ee a pe — lat obtaining satisfaction from their N the future the frantic calls of distreasedk ships cannot fall on the edead ears’ of nearby vessels, proyidcrd they are equipped with the new radio danger sigual device receutly invented hy the Marconi Co. In the past. distress sicnals were not always ‘intercepted by the ships nearest to the ‘one i trouble, This was due to the -fact thet all vessels cannot earry & full radio watch. As a conseque©nce, the SOS signal of the distressed boat could eusily be missed if the radio operator was off duty. After many years’ experimenting, the Marconi Co. Have finally perfected a device, which goes on duty when the operator goes eff. This device bas only to be switched on to the ship’s aerial. Twelve . three-second wireless dashes with a one-second rest inferval between each ‘dash is the prearranged signal. After ‘the third dash of this. signal is re-} ceived by the Marconi device, it im- | mediately calls the radio operator back ‘to his post by ringing @ series of ship’s | bells. v a i yur most prevalent form of manmade interference as distinct from natural inferference, such as atmo‘snerics, etc., is that caused by electric machinery or supply systems. It is possible, of course, to obtain perfect reception near electric systems, but if they are not designed or maintained with any consideration of their in‘fence as generators of radio interference, the listeners within the sphere of intiuence have a bad time. Some | }eountry residents know too well how f Fsuddenly and completely their enjoytment of broadcasting ceases for the | night immediately a picture show opens up; while others know that Levery night is spoiled for reception | when a medical man with his electrotherapy apparatus starts his high frequencies oscillating. There are towns where the supply system is the cause lof continual "static" as it is frequently called locally, and listeners efforts sets are practically nil. AUSTRALIA has had a plethora of notabilities lately, all of whom have been captured and brought face to face with the microphone. Winkler, perhaps, holds the record for being Lthe most broadcast man of the year, Beginning with his arrival at Darwin, he has continuously held the chief place in radio transmission, either getting or receiving long-distance mesbsages while Australia either looked on or listened in. a3 E YI !, Sydney, which, owing to its stupendous income, is putting on the air some wonderful programmes, is, of eourse, not free from criticism. One Sydney growler writes to the Press as | follows :-A couple of nights back I | heard "Mike" (the young rascal) skiting about the good programmes that }2K'C puts on the air. Well, they do, but+ I must say that a lot of it is. "high-brow" and passes over the heads: of "us way-backs" and "eow robbers." Frinstance! Mr, Cochrane (may his elbow never weaken) says that Professor So and So will now play "Allegro toute Suite in a B flat," and some bloke sits down (or I suppose he does}, and drags out some notes at the rate of about 60 hours a mile, and .as my crystal set can only get 20 r (when it is on the alr the others are drowned out), I have to listen in ov wait for the next item, ~~

USSIA has 45 broadcasting stations ranging in. power from 20 watts: to 40, 000, and in wavelength from 150 to 1117 metres, , vce radio trouble ean be traced to particles of dust getting between the condenser plates. The moral iskeep your condensers clear. A pipe cleaner is a very. handy article for cleaning between the: plates, as it is umnecessary to take the condenser apart. . jf OSEPH HENRY, the American scientist, was the first man to point ont that the charge of a condenser is oscillatory. This was in 1840, "PE ability of an aerial to collect energy depends directly on __ its height. Thus, for a crystal receiver, which should have as much energy from the aerial as possible, no pains should be spared to make it as high as possible, and as far above and away from trees and buildings as the resources of. the listener will permit. If a valve set is used, an excessively long avrial is sometimes an embarrassment rather than a help. There are two main reasons for this, In the first place a very long aerial will collect a great deal of static, and reception will be marred. This effect is not so pronounced on a crystal receiver, The'second objection to a long aerial for valve reception is that it tends to broaden tuning, and a weak station is difficnlt to pick up without interference while a powerful one is working A crystal receiver is inherently broad in inning, and this effect of a long arrial therefore is. of little importance. TPHE most reliable method of determining the degree of cha: ge received by an accumulator {wet battery) is by means of a hydrometer. This consisis of a glass float in a glass tube. There is a scale upon the upper portion of the float which rises or falls according to the density of the liquid in which it is floating, thus indicating the condition of the liquid. When the accumulator is fully charged its electrolyte will have a specific gravity of approximately 1.250. It is tict advisable to allow the electrolyte to fall below a specific gravity of LIéG. When this figure is approached, the accumulator should be recharged as socn as possible to prevent possible damage to the cells. 'IYHE Japanese Government has decided to revoke its previous decision to prohibit the operation of radio apparatus by amateurs. The result is that a large number of the Japs. are already in operation under rew call signs of four letters, and the recd for secrecy is happily passed. "PHE old-fashioned plan of reversing audio transformer connections is often very effective in reducing the hum due to a B battery eliminator or a mains unit, : N ARCONI first went to England in 15U6, and his first experiments in that country were carried out at Westbourne Park, London,. W. GET-BUILDERS should note that sometimes the binding posts on transformers have the end of the winding soldered to the bottom end, and you can céasily break the connection With the small wire by turning the whole binding post. After the binding post cap has been firmly tiehtened and you continue to turn up the cap the whole binding post will rotate. 'XNE Radio Corporation of America has applied for two exclusive short wavelengths, for use in exchanging programines with Britain. TRHERIE was a dramatic interruption at 40G, Brisbane, during the time Bert Hinkler was speaking some few nights ago. A moth attracted by the bright valves crossed a safety gap and short-circuited the high-tension supply. The station was off the air for a few moments, and the director of the station explained to Mr. Hinkler what had happened. When the station was started up again the microphone was switched on, Winkler remarked that he did not intend to say much about that moth, but could not help remarking that an Avro Avian had much better habits, and woifd not have done a thing like that. ‘The secret of the joke lies of course in the fact that the "moth"? is another type of light aeroplane, a contemporary of the Avro Avian. py the Orange Mountains, 22 miles from New York city, is the Bell elephone Yaboratories experimental broadcast station, 3XN, which operates with an aerial power of 50,000 watts, requiring 200,000 watts input. It is on the air from midnight on ‘Thursday till 4 a.m., New York time. A RATHER interesting design of valve, for heating directly from the A.C. mains, is due to another French inventor, Monsieur Havardier. In this valve two filaments are used, connected together in parallel, but the leads to the one are the opposite way from those to the other, so that the current passes through the two filaments (which are placed close to gether, side by sidc) in opposite directions. In conseqnence of this, the general distorting effects of the current in the two filaments balance each other. The filaments are designed to emit at a very low temperature, and the valve’ has given very good results in actual practice,