NOTES AND COMMENTS

Radio Record, Volume I, Issue 33, 2 March 1928, Unnumbered Page

NOTES AND COMMENTS

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How the. love cf "good’’ music is being extended from the select circle of cultured groups to the general public is explained by an American writer, as follows: "In spite of all generallyaccepted theories to the contrary, the middle classes of America are being coated with culture, and the germ of this culture, which is carried on the radio waves, is penetrating far deeper than the surface. They may be rntutored in knowledge of the art of the brush and paint, they may be ignorant of the value of classic lines in clay, but when it comes to the notes of music, they know their operas and they know their artists." The ‘Scientific American’’ says of the new American double-grid valve: ‘"This_ UX-222, when properly connected, is said to increase the signal voltage about 30 to 40 times, as compared with a five to seven voltage increase obtained with the average general purpose valve.’ When emploved as a spsee-charge-grid valve, the received signal voltage may be intensified by more than -150 times per stage of amplification. ‘The tube requires but .182 amperes of filament current at a voltage of 3.3. The dream of radio as a means of individual and secret erammunication between persons or any two desired Places on earth is fading away, accord-ing-to Dr. J. H. Dellinger, chief of the radio laboratorv of the United States Government Burean of Standards. "The directing of radio waves in a very sharnlv defined beam, like light from a searchlight, is a consummation not likely to be achieved," savs Dr. Dellinger, ‘Nevertheless, the approximations that have heen and ‘are being made are of erent value. Abont ten vears ago, Marconi demonstrated that. hy the nse of a parabolic -reflectine arrangement, radio waves could be nartlv directed in a definite Cirection. With such an arrangement the intensity of the waves alone the desired direction was several times that found at aneles treater than 20 Aorrens fram tiat directien." _Manv vernier dials are operated on a friction principle and their use in a receiver is often interfered with bv the mechanical construction of the variable condenser which thev actuate. A great number of condensers are eauipped with a braking mechanism to provide various tensions in resnect to the ease with which the shaft -mav he revolved Manv condensers are adjusted at the factory so that a considerable amount of tension is present A. friction driven vernier flial will slip when used in conjunction with such a condenser and is snhject to considerable ‘"back-lash." Tlie use of a screwdriver or pliers, as the case mav be, will allow the braking mechanism to be loosened so that operation of the vernier dial will he mast. satisfactory A careful examination of the condenser will usuallv disclose just what port acts as the brake. As manv as 325 words per minute in both directions have heen sent by beam radio between Australia and Eng. land. Are there anv ‘fans’? who can read morse at that speed Dr Irvine Wolft, a prominent American radio engineer, savs that the sound given off by the loudspeaker depends both upon the efficiency of the radiating surface and its amplitude. of motion, and that -low tones can be obtained from even a small surface by making the motion large. The majority of loudspeaker cords have one of the wires equipped with a red tracer The wire thus marked should at all times be connected to the "B" positive of the loudspeaker output of the receiver unless an output transformer is used Damage may result to the speaker if the ‘‘B" battery voltage is applied to the wrong terminal. A convenient method for testing whether or not the polarity is correct is to connect the speaker to the output of the receiver and observe the quality and volume of reproduction. Then reverse the terminals and repeat. If the volume and reproduction is of a better order, it is safe to allow the cormnections to remain. Tf, on the other hand, a decided decrease in quality and volume is observed, reverse the terminals to their origina] polarity. A New York radio authoritv says :- "An error in popular discussion of recent super-power developments, particularly with respect to WGY’s (Schenectady) 100-kilowatt set. is the assumption that doubling the power douhles tle effective range. At the time WJZ’s present equipment was installed, engineers explained that, because of the ‘square-root rule,’ which applies in such a case, it is necessarv to increase the power four times in order ta double the sienal strenoth, which means 200, and not 100 kilowatts, is the next step in power increases, but one not expected in the near future.’ he constables of the Police Department in Passiac, N.J., U.S.A., have each been supplied with a pocket receiving set, with which they are able to receive messages from headquarters whilst on their beat. The inventor of the systenr is Michael Rush. .

LL LOL LOT ET LS Ne $= Operating from the roof of W. H. Knight and Peter Bros.’ showroom in Launceston, station 7UX was recently heard in America. Mr. Steane, whe operated the transmitter, claims to have established a record for long dis tance transmission of telephony, using low power, since receiving the follows ing letter from Mr. W. McDonald, of Chula Vista, California:-‘Karly this morning I tuned in a station giving its call sign as 7UX. The time corresponded with 10 p.m. in Australia. The station transmitted musical items for about an hour, and I shonld be glad to know if this was your transimssion." At the time 7UX was using power of the order of 20 watts, which makes the feat all the more remarkable, stuce the normal night range of a 200 metre station using this power is from 500 to 1000 miles. This is the second time that the Tasinanian stae tion has been heard in U.S.A The Berlin broadcast station shortly intends to make an experiment in the transmission of a complete opera in which the principal songs, duets, and quartets will be given from gramophone records, the whole production to be linked together by the station ore chestra. By this means, points out the London ‘‘Amateur Wireless,’’ it is thought possible to produce a radio version of a famous opera to which famous singers, both dead and living, wil] contribute. Mr. Clement Hosking, musica] direetor of 2GB, the ‘Theosophical Society’s Sydney station, states:-‘‘We are constantly being asked to perform jazz, but we do not feel that jazz is pars ticularly inspiring, and simply refuse to comply with these requests. Before long we hope to have plenty of good, clean bumour.’"

A wireless and travel exhibition 1s to be held at Bandoeng, Java, during june and july, lds. ioe introduction of the wireless element is due to the wireless boom which is now sweeping the country, conseyuent upon the recent law permitting private ownership of receiving sets. Difficulty is sometimes experienced im drilling holes in sheet metal used for interstage screening, especially it the material is thin. As a rule, it. will be found better to punch the hole; provided a soft metal, such as copper or ‘aluminium, is used, there is no need for any special tool, as a rod of steel ‘er even. brass, with one end filed square, will serve quite well It 1s essential, however, that the sheet in which the hele is to be made should be rested on the end grain of a piece of /kardwood or similar material. Mr. C. A. Blackington, of Wrangell, Alaska, reports to the New York ‘‘Radio News" that he has heard 2YA, Wel. lington, 8YA, Cliristchurch, and 1YA, Auckland. A photograph of his set was published in the ‘‘Radio Record’? some months back. Speaking to an interviewer in New York a few weeks ago, Marconi, referring to the benefit of short waves to the man with a receiving set in his home, said ‘Short waves are beginning to show unhoped for results in improving broadcasting by making it workable over great distances, even during dayHght hours. And directive {(heam} methods will soot be utilised for broadcasting by enabling programmes and speeches to be sent over large portions of America and to foreign countries, with much more strength and freedom from interference than is possible now." Arthur T. Brown, writing in the New York ‘Radio News,’ says :-‘‘People do listen to religious broadcasts-in-deed, according to investigations made by some of the larger stations, these come next, after music, in popularity. That this is so need surprise no one. Religion, whether it be the Faith handed down through the Christian cen-turies-not to mention the Jewish, centuries before them-or some faith so new its official stationery has not yet come from the printer, 1s, next after bread and butter on the one hand, and love on the other, the most engrossing of human interests. It is so because we all live by faith, even though our aith be only fhe minimum of the agnostic, viz., that human intelligence is entirely inadequate to receive ultimate truth,’’ All radio listeners m Australia (says the Sydney ‘‘Wireless Weekly’), use che broadcasting stations for the purpose of setting their clocks aud watches; most jewellers and watchmakers rcly on the broadcast time signals to give them the exact time. ‘The practice of brvadcasting the British time signals, however, seems to be upsetting calculations, because a few nights ago the striking of Big Ben, London, was heard over the air, and at the same time our own Sydney G.P.O. clock was heard to strike. The curious thing was that there was a difference of 15 seconds between the two clocks, and as the Sydney clock is always correct to within 5 seconds, Big Ben must have been at least ten’ seconds out, possibly more. Of course, Big Ben is 10 hours behind us if any case-a fact which was a surprise to many listeners in Australia when they first heard him over the radio. A loose contact at the grid leak may be the origin of troublesome and mysterious noises, often hard to locate. ‘lo prevent such troubles, the best plan is to bend the clips of — the grid leak holder inward with a pair of pliers. This will insure a_ tight grip and positive contact, and hence there will be mo chance of noises originating at this point. It was reported from Washington ou January 5.-‘"Wired Radio, Inc., of 60 Broadway, New York City, has applied to the Federal Radio Commission for permission to rebroadcast programmes over electric lighting systems. The commission responded that the application cannot be granted prior to the short wave hearings scheduled for January 17, since use of short waves is involved in the application. The request was for permission to use three frequencies in the band commencing with 1500 kilocycles. Programines would be picked up in New York aud transmitted bv wire to listeuers. The commission regards the application with much interest, since it may offer prospects for a new radio system. If electric lighting systems are used and tlhe plan should become popular, it was declared, the wav might be opened for charging users of programmes to broadcast.’' The Wesftralian station, 6WF, Perth, may be heard in New Zealand without the bother of installing a set which will tune to 1250 metres. Dual transmissions are being carried ont on the usual wavelength and on 104.5 metres. On the low wave New Zealand listeners should have no difficulty in logging GWI* on a three-valye receiver. ‘The transmissions are excellent, modulation being very nearly perfect. ‘The only trouble is that the static which is prevalent on these wavelengths at this time of the year interferes occasionally. ‘the staton is usually passed over as a harmonic of one of the broadcasters, and this is probably the reason whiy the transformers are received here by so few short wave lis-. tenera,

An American authority states that wireless receiving equipment for aeroplanes must be light in weight and very compact, yet be accessible in flight for simple adjustinents and occasional replacements of valves. Reception is rendered difficult, not only by the motor aud propellor noises, but also is often considerably interfered with by the engine ignition system, which itself acts like a broadly tuned spark transmitter, Interference can be entirely eliminated only by surrounding all parts and wiring of the ignition system with metallic "shielding,’’ grounded at frequent interyale to . the engine structure, Engineers of WCY, Schenectady, arc hopeful that the management of 2FC, Sydney, may be interested in transmitting a special short-wave programme for the United States at an hour when more listeners will- find it convenient to be at their radio sets, This would mean that Australia must start its programme abont 6 a.m. We in New Zealand are not alone in finding 4QG, Brisbane, badly blurred. An Australian listener writes to the Sydney ‘Wireless Weekly" as follows: *‘Say, what’s wrong with 40G modulation? The announcer gets terrible hoarse after 8 p.m, (any kind of set).. We poured a bottle of beer down the loudspeaker to give him a drink, but they all seem to suffer the same at 40G, even the ladies." When is friend Robinson, director of 4QG, going to do something about it? The Swiss Marconi Company are building a high-powered station (50,000 watts power) for the League of Nations which will be capable of reaching all places in Ifurope, North Africa and the Fast. Instead of soldering the ordinary lug to stranded wire (which operation calls for some skill), it is a better plan to twist the loose strands of the wire together and bend them in the form of a hook, By running solder in between the strands a good Iug can be made. The best way to run the solder is to first place a piece of solder on the Iug, then hold it over a flame, then the solder will run between the strands, thus making a most efficient lug. The introduction of a wireless telephony service between ships and the mainland is reported to be under consideration by the German postal authorities. Although the idea 1s still in the experimental stage, certain tests which have already been made, show that a practical service is quite possible in the future. By means of a small piece of fuse wire and a short length of ebonite rod, an effective accumulator fuse can be constructed in a few moments. One of the terminal tops is removed and replaced by a short ebonite pillar, and the fuse wire is connected to both the top and bottom of the pillar, the terminal top being screwed upon it. If your receiving set will not tune down to the shorter wavelengths on the normal broadcast band, you may be missing the programmes that are put on by stations that use wavelengths below three hundred metres. You can get in on these low wavelengths by inserting a 21 plate variable condenser in the aerial cirenit. When not in use, the condenser can be short circuited with a piece of bus-bar or a switch. Where a sinall variable condenser is shown in the circnit of a short wave receiving set, this can easily be constructed fromm two halfpennics and two pieces of bus-wire. TVirst sandpaper the halfpennies until they shine, then on each solder a piece of bus-bar, of tlic square yaricty. The bus-bar strips should he three inches long. One of them should have the end turned at right angles an inch away from the end that is not soldered to the coin. ‘his is your fixed plate, and is firmly clasped by a terminal screwed to a piece of bakelite. ‘The other coin, which is your moving plate, is held by a movable terminal, in order that it may he moved to and fro from your fixed plate, ‘The leads are taken to the bottoms of the two terminals, | ee |